[RISC-V] Synthesizing PC-relative pointer constants - #119203

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tomeksowi:pc-rel-pointers
Dec 1, 2025
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[RISC-V] Synthesizing PC-relative pointer constants#119203
jakobbotsch merged 43 commits into
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tomeksowi:pc-rel-pointers

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@tomeksowi

@tomeksowitomeksowi commented Aug 29, 2025

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RISC-V is ill-equipped to synthesize large >32-bit constants like absolute pointers, it results in a 6-8 instruction sequence. If an address can be synthesized as PC-relative (2 instructions: auipc + ld/addi), do so. It also simplifies codegen.

Part of #84834, cc @dotnet/samsung

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@clamp03clamp03 added the arch-riscv Related to the RISC-V architecture label Sep 1, 2025
@tomeksowi

tomeksowi commented Sep 1, 2025

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@risc-vv /run

@risc-vv

risc-vv commented Sep 1, 2025•
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RISC-V pull_request-CLR-QEMU: 9108 / 9139 (99.66%)
=======================
passed: 9108
failed: 3
skipped: 586
killed: 28
------------------------
TOTAL tests: 9725
VIRTUAL time: 80h 13min 42s 134ms
REAL time: 1h 18min 35s 828ms
=======================

report.xml, report.md, failures.xml, testclr_details.tar.zst

RISC-V pull_request-CLR-VF2: 9108 / 9139 (99.66%)
=======================
passed: 9108
failed: 3
skipped: 586
killed: 28
------------------------
TOTAL tests: 9725
VIRTUAL time: 32h 6min 37s 777ms
REAL time: 2h 7min 32s 224ms
=======================

report.xml, report.md, failures.xml, testclr_details.tar.zst

RISC-V pull_request-FX-QEMU: 0 / 0 (100.00%)
=======================
passed: 0
failed: 0
skipped: 14
killed: 0
------------------------
TOTAL tests: 14
VIRTUAL time: 0ms
REAL time: 4h 30min 0s 477ms
=======================

report.xml, report.md, failures.xml, testclr_details.tar.zst

RISC-V pull_request-FX-VF2: 0 / 61 (0.00%)
=======================
passed: 0
failed: 0
skipped: 14
killed: 61
------------------------
TOTAL tests: 75
VIRTUAL time: 1min 14s 744ms
REAL time: 13h 0min 6s 48ms
=======================

report.xml, report.md, failures.xml, testclr_details.tar.zst

Build information and commands

GIT: bd0e79cc0470c7eae53ef67028e7c567c9fb9846
CI: 0dd2da79b21e6d27378407c3af1305973fd300aa
REPO: dotnet/runtime
BRANCH: main
CONFIG: Checked
LIB_CONFIG: Release

@tomeksowi

tomeksowi commented Sep 1, 2025

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No regressions. Quite a bit of post-bringup cruft went out the window.

Diffs are based on 104,367 contexts (2,270 MinOpts, 102,097 FullOpts).

MISSED contexts: 2 (0.00%)

Overall (-9,469,872 bytes)
CollectionBase size (bytes)Diff size (bytes)PerfScore in Diffs
linux.riscv64.Checked.3.mch71,889,656-9,469,872-7.46%
MinOpts (-2,342,108 bytes)
CollectionBase size (bytes)Diff size (bytes)PerfScore in Diffs
linux.riscv64.Checked.3.mch16,685,964-2,342,108-7.73%
FullOpts (-7,127,764 bytes)
CollectionBase size (bytes)Diff size (bytes)PerfScore in Diffs
linux.riscv64.Checked.3.mch55,203,692-7,127,764-7.45%
Example diffs
linux.riscv64.Checked.3.mch
-48 (-41.38%) : 53568.dasm - Program:Main():int (FullOpts)
@@ -20,35 +20,23 @@ G_M24375_IG01: ; bbWeight=1, gcrefRegs=0000 {}, byrefRegs=0000 {}, byref,
mv fp, sp
;; size=16 bbWeight=1 PerfScore 9.00
G_M24375_IG02: ; bbWeight=1, gcrefRegs=0000 {}, byrefRegs=0000 {}, byref
- lui t6, 0xD1FFAB1E- addiw t6, t6, 0xD1FFAB1E- slli t6, t6, 13- addi t6, t6, 0xD1FFAB1E- slli t6, t6, 2- ld a0, 0xD1FFAB1E(t6)+ auipc a0, 0xD1FFAB1E+ ld a0, 0xD1FFAB1E(a0)
jalr a0 // <unknown method>
- lui t6, 0xD1FFAB1E- addiw t6, t6, 0xD1FFAB1E- slli t6, t6, 13- addi t6, t6, 0xD1FFAB1E- slli t6, t6, 2- ld a0, 0xD1FFAB1E(t6)+ auipc a0, 0xD1FFAB1E+ ld a0, 0xD1FFAB1E(a0)
jalr a0 // <unknown method>
- lui t6, 0xD1FFAB1E- addiw t6, t6, 0xD1FFAB1E- slli t6, t6, 13- addi t6, t6, 0xD1FFAB1E- slli t6, t6, 2- ld a0, 0xD1FFAB1E(t6)+ auipc a0, 0xD1FFAB1E+ ld a0, 0xD1FFAB1E(a0)
jalr a0 // Test:Ret():int
- ;; size=84 bbWeight=1 PerfScore 30.00+ ;; size=36 bbWeight=1 PerfScore 15.00
G_M24375_IG03: ; bbWeight=1, epilog, nogc, extend
ld ra, 8(sp)
ld fp, 0(sp)
addi sp, sp, 16
ret ;; size=16 bbWeight=1 PerfScore 7.50
-; Total bytes of code 116, prolog size 16, PerfScore 46.50, instruction count 17, allocated bytes for code 116 (MethodHash=d9b8a0c8) for method Program:Main():int (FullOpts)+; Total bytes of code 68, prolog size 16, PerfScore 31.50, instruction count 14, allocated bytes for code 68 (MethodHash=d9b8a0c8) for method Program:Main():int (FullOpts)
; ============================================================
Unwind Info:
@@ -59,7 +47,7 @@ Unwind Info:
E bit : 0
X bit : 0
Vers : 0
- Function Length : 58 (0x0003a) Actual length = 116 (0x000074)+ Function Length : 34 (0x00022) Actual length = 68 (0x000044)
---- Epilog scopes ----
---- Scope 0
Epilog Start Offset : 3523193630 (0xd1ffab1e) Actual offset = 3523193630 (0xd1ffab1e) Offset from main function begin = 3523193630 (0xd1ffab1e)
-32 (-40.00%) : 54962.dasm - ExceptionExtensions:RethrowWithNoStackTraceLoss(System.Exception) (FullOpts)
@@ -21,26 +21,18 @@ G_M64910_IG01: ; bbWeight=0, gcrefRegs=0000 {}, byrefRegs=0000 {}, byref,
;; size=16 bbWeight=0 PerfScore 0.00
G_M64910_IG02: ; bbWeight=0, gcrefRegs=0400 {a0}, byrefRegs=0000 {}, byref
; gcrRegs +[a0]
- lui t6, 0xD1FFAB1E- addiw t6, t6, 0xD1FFAB1E- slli t6, t6, 12- addi t6, t6, 0xD1FFAB1E- slli t6, t6, 3- ld a1, 0xD1FFAB1E(t6)+ auipc a1, 0xD1FFAB1E+ ld a1, 0xD1FFAB1E(a1)
jalr a1 // System.Runtime.ExceptionServices.ExceptionDispatchInfo:Capture(System.Exception):System.Runtime.ExceptionServices.ExceptionDispatchInfo
- lui t6, 0xD1FFAB1E- addiw t6, t6, 0xD1FFAB1E- slli t6, t6, 12- addi t6, t6, 0xD1FFAB1E- slli t6, t6, 3- ld a1, 0xD1FFAB1E(t6)+ auipc a1, 0xD1FFAB1E+ ld a1, 0xD1FFAB1E(a1)
lw zero, 0xD1FFAB1E(a0)
jalr a1 // System.Runtime.ExceptionServices.ExceptionDispatchInfo:Throw():this
; gcrRegs -[a0]
ebreak
- ;; size=64 bbWeight=0 PerfScore 0.00+ ;; size=32 bbWeight=0 PerfScore 0.00-; Total bytes of code 80, prolog size 16, PerfScore 0.00, instruction count 12, allocated bytes for code 80 (MethodHash=95e60271) for method ExceptionExtensions:RethrowWithNoStackTraceLoss(System.Exception) (FullOpts)+; Total bytes of code 48, prolog size 16, PerfScore 0.00, instruction count 10, allocated bytes for code 48 (MethodHash=95e60271) for method ExceptionExtensions:RethrowWithNoStackTraceLoss(System.Exception) (FullOpts)
; ============================================================
Unwind Info:
@@ -51,7 +43,7 @@ Unwind Info:
E bit : 0
X bit : 0
Vers : 0
- Function Length : 40 (0x00028) Actual length = 80 (0x000050)+ Function Length : 24 (0x00018) Actual length = 48 (0x000030)
---- Epilog scopes ----
No epilogs
---- Unwind codes ----
-40 (-38.46%) : 856.dasm - Interop:g__ParentDirectoryExists|7_0(System.String):bool (FullOpts)
@@ -22,25 +22,15 @@ G_M36700_IG01: ; bbWeight=1, gcrefRegs=0000 {}, byrefRegs=0000 {}, byref,
;; size=16 bbWeight=1 PerfScore 9.00
G_M36700_IG02: ; bbWeight=1, gcrefRegs=0400 {a0}, byrefRegs=0000 {}, byref
; gcrRegs +[a0]
- lui t6, 0xD1FFAB1E- addiw t6, t6, 0xD1FFAB1E- slli t6, t6, 13- addi t6, t6, 0xD1FFAB1E- slli t6, t6, 2- ld a1, 0xD1FFAB1E(t6)+ auipc a1, 0xD1FFAB1E+ ld a1, 0xD1FFAB1E(a1)
jalr a1 // System.IO.PathInternal:TrimEndingDirectorySeparator(System.String):System.String
- lui t6, 0xD1FFAB1E- addiw t6, t6, 0xD1FFAB1E- slli t6, t6, 32- srli t6, t6, 18- ld a1, 0xD1FFAB1E(t6)+ auipc a1, 0xD1FFAB1E+ ld a1, 0xD1FFAB1E(a1)
jalr a1 // System.IO.Path:GetDirectoryName(System.String):System.String
- lui t6, 0xD1FFAB1E- addiw t6, t6, 0xD1FFAB1E- slli t6, t6, 32- srli t6, t6, 18- ld a1, 0xD1FFAB1E(t6)- ;; size=72 bbWeight=1 PerfScore 25.00+ auipc a1, 0xD1FFAB1E+ ld a1, 0xD1FFAB1E(a1)+ ;; size=32 bbWeight=1 PerfScore 12.00
G_M36700_IG03: ; bbWeight=1, epilog, nogc, extend
ld ra, 8(sp)
ld fp, 0(sp)
@@ -48,7 +38,7 @@ G_M36700_IG03: ; bbWeight=1, epilog, nogc, extend
jr a1 // System.IO.Directory:Exists(System.String):bool
;; size=16 bbWeight=1 PerfScore 7.50
-; Total bytes of code 104, prolog size 16, PerfScore 41.50, instruction count 16, allocated bytes for code 104 (MethodHash=027470a3) for method Interop:<GetExceptionForIoErrno>g__ParentDirectoryExists|7_0(System.String):bool (FullOpts)+; Total bytes of code 64, prolog size 16, PerfScore 28.50, instruction count 13, allocated bytes for code 64 (MethodHash=027470a3) for method Interop:<GetExceptionForIoErrno>g__ParentDirectoryExists|7_0(System.String):bool (FullOpts)
; ============================================================
Unwind Info:
@@ -59,7 +49,7 @@ Unwind Info:
E bit : 0
X bit : 0
Vers : 0
- Function Length : 52 (0x00034) Actual length = 104 (0x000068)+ Function Length : 32 (0x00020) Actual length = 64 (0x000040)
---- Epilog scopes ----
---- Scope 0
Epilog Start Offset : 3523193630 (0xd1ffab1e) Actual offset = 3523193630 (0xd1ffab1e) Offset from main function begin = 3523193630 (0xd1ffab1e)
+0 (0.00%) : 104032.dasm - Microsoft.Diagnostics.Tracing.TraceEvent:get_FormattedMessage():System.String:this (FullOpts)
@@ -22,6 +22,7 @@ G_M51530_IG01: ; bbWeight=1, gcrefRegs=0000 {}, byrefRegs=0000 {}, byref,
G_M51530_IG02: ; bbWeight=1, gcrefRegs=0400 {a0}, byrefRegs=0000 {}, byref
; gcrRegs +[a0]
mv a1, zero
+ ; gcrRegs +[a1]
ld a2, 0xD1FFAB1E(a0)
ld a2, 0xD1FFAB1E(a2)
ld a2, 0xD1FFAB1E(a2)
+0 (0.00%) : 57024.dasm - UDivConst:U8_Div_3(ulong):ulong (FullOpts)

No diffs found?

+0 (0.00%) : 56976.dasm - SlowPathELTTests.SlowPathELTHelpers:MixedSseStructFunc():SlowPathELTTests.MixedSseStruct (FullOpts)

No diffs found?

Details

Size improvements/regressions per collection

CollectionContexts with diffsImprovementsRegressionsSame sizeImprovements (bytes)Regressions (bytes)
linux.riscv64.Checked.3.mch78,13976,85401,285-9,469,872+0

PerfScore improvements/regressions per collection

CollectionContexts with diffsImprovementsRegressionsSame PerfScoreImprovements (PerfScore)Regressions (PerfScore)PerfScore Overall in FullOpts
linux.riscv64.Checked.3.mch78,13957,537020,602-9.99%0.00%-5.6031%

Context information

CollectionDiffed contextsMinOptsFullOptsMissed, baseMissed, diff
linux.riscv64.Checked.3.mch104,3672,270102,0972 (0.00%)2 (0.00%)

jit-analyze output

@tomeksowi

tomeksowi commented Sep 1, 2025

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+0 (0.00%) : 104032.dasm - Microsoft.Diagnostics.Tracing.TraceEvent:get_FormattedMessage():System.String:this (FullOpts)
@@ -22,6 +22,7 @@ G_M51530_IG01: ; bbWeight=1, gcrefRegs=0000 {}, byrefRegs=0000 {}, byref,
G_M51530_IG02: ; bbWeight=1, gcrefRegs=0400 {a0}, byrefRegs=0000 {}, byref
; gcrRegs +[a0]
mv a1, zero
+ ; gcrRegs +[a1]
ld a2, 0xD1FFAB1E(a0)
ld a2, 0xD1FFAB1E(a2)
ld a2, 0xD1FFAB1E(a2)

Looks like a bonus fix. Notice how this code I removed also silently stripped GC flags.

runtime/src/coreclr/jit/codegenriscv64.cpp

Lines 902 to 905 in f1cbe0f

if (!compiler->opts.compReloc)
{
size = EA_SIZE(size); // Strip any Reloc flags from size if we aren't doing relocs.
}

@tomeksowi
tomeksowi marked this pull request as ready for review September 2, 2025 06:23
@JulieLeeMSFT

JulieLeeMSFT commented Oct 6, 2025

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We will review .NET 11 PRs when we are done with .NET 10 last minute works and less busy. Please give us a few more weeks.
CC @jakobbotsch.

@steveisoksteveisok added this to the 11.0.0 milestone Oct 6, 2025
@jakobbotsch

jakobbotsch commented Oct 21, 2025

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@EgorBo Do we need a fix for arm64 version of the code @tomeksowi points at above?

runtime/src/coreclr/jit/codegenarm64.cpp

Lines 2098 to 2101 in 25e088f

if (!compiler->opts.compReloc)
{
size = EA_SIZE(size); // Strip any Reloc flags from size if we aren't doing relocs
}

For address 0 it is clearly not a problem -- would it be a problem for frozen objects?

@jakobbotsch

jakobbotsch commented Oct 21, 2025

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If an address can be synthesized as PC-relative (2 instructions: auipc + ld/addi), do so.

Note that it's generally impossible to know where the code will be located, so you can only do this heuristically. How do you recover when you get it wrong?

For x64 we recover the situation by disabling rip-relative addressing globally the first time it happens, and then designing things so that it very rarely happens. Look for m_fAllowRel32.

@EgorBo

EgorBo commented Oct 21, 2025

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@EgorBo Do we need a fix for arm64 version of the code @tomeksowi points at above?

Do you mean it may strip the GC related flags for frozen objects? I think we don't report them to GC anyway, do we?

@tomeksowi

tomeksowi commented Oct 22, 2025

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Note that it's generally impossible to know where the code will be located, so you can only do this heuristically. How do you recover when you get it wrong?

For x64 we recover the situation by disabling rip-relative addressing globally the first time it happens, and then designing things so that it very rarely happens. Look for m_fAllowRel32.

I don't recover, the address of a handle with function address was always within range, but you're right, IsIconHandle(GTF_ICON_FTN_ADDR) is just a heuristic. I remember looking at m_fAllowRel32 briefly but abandoned it because it seemed linked to jump stubs which RISC-V doesn't use (and aren't applicable here since we're doing loads for the handles).

I'll try to use it, maybe communicating failure with m_fJumpStubOverflow = TRUE to reuse existing codepaths, then eeGetRelocTypeHint on the handle value should tell me which way to go.

@jakobbotsch

jakobbotsch commented Oct 22, 2025

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For x64 there is a contract between the JIT and VM about when and how relative addressing is used: for data addresses PC-relative addressing can only be used based on getRelocTypeHint. For code addresses PC-relative addressing can always be used, and the VM will create jump stubs if necessary.

If you are using PC-relative addressing for data addresses then I expect you need to build a similar system. If you are only using it for code addresses, then I expect you need to support some form of jump stubs.

@jakobbotsch

jakobbotsch commented Oct 22, 2025

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@EgorBo Do we need a fix for arm64 version of the code @tomeksowi points at above?

Do you mean it may strip the GC related flags for frozen objects? I think we don't report them to GC anyway, do we?

Yes, that's what I meant. I was not sure if they GC refs to frozen objects need to be reported or not. If not then it seems ok.

@EgorBo

EgorBo commented Oct 22, 2025

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@EgorBo Do we need a fix for arm64 version of the code @tomeksowi points at above?

Do you mean it may strip the GC related flags for frozen objects? I think we don't report them to GC anyway, do we?

Yes, that's what I meant. I was not sure if they GC refs to frozen objects need to be reported or not. If not then it seems ok.

I think in fact we do report them today, but don't have to

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For linux-musl-riscv64

Comment threadsrc/coreclr/vm/jitinterface.cpp Outdated
Comment threadsrc/coreclr/vm/jitinterface.cpp Outdated
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Comment threadsrc/coreclr/tools/superpmi/superpmi-shared/compileresult.cpp Outdated
tomeksowiand others added 2 commits November 19, 2025 20:16
@tomeksowi@am11
fix musl build
80a6998
Co-authored-by: Adeel Mujahid <3840695+am11@users.noreply.github.com>
@tomeksowi
lower bool
062652b
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@tomeksowi
tomeksowi marked this pull request as ready for review November 25, 2025 10:42
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Merged
@tomeksowi
Merge branch 'main' into pc-rel-pointers
abacec7
Conflicts:
src/coreclr/inc/corinfo.h
src/coreclr/jit/emitriscv64.cpp
src/coreclr/tools/Common/JitInterface/CorInfoImpl.cs
src/coreclr/tools/superpmi/superpmi-shared/compileresult.cpp
src/coreclr/vm/jitinterface.cpp
@tomeksowi
Fix build
8c081a6
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Fix types and format
e5ce631
@jkotas

jkotas commented Nov 27, 2025

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VM side LGTM.

@dotnet/jit-contrib Could you please review the JIT side?

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[RISC-V] Fix too many arguments build error in emitIns_R_AI (#122555)
46de0c9
Fixes#122553, regression after #119203.
Part of #84834, cc @dotnet/samsung
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[RISC-V] Synthesizing PC-relative pointer constants - #119203
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[RISC-V] Synthesizing PC-relative pointer constants#119203
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RISC-V is ill-equipped to synthesize large >32-bit constants like absolute pointers, it results in a 6-8 instruction sequence. If an address can be synthesized as PC-relative (2 instructions: auipc + ld/addi), do so. It also simplifies codegen.
Part of #84834, cc @dotnet/samsung
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RISC-V pull_request-CLR-QEMU: 9108 / 9139 (99.66%)
=======================
passed: 9108
failed: 3
skipped: 586
killed: 28
------------------------
TOTAL tests: 9725
VIRTUAL time: 80h 13min 42s 134ms
REAL time: 1h 18min 35s 828ms
=======================

report.xml, report.md, failures.xml, testclr_details.tar.zst
RISC-V pull_request-CLR-VF2: 9108 / 9139 (99.66%)
=======================
passed: 9108
failed: 3
skipped: 586
killed: 28
------------------------
TOTAL tests: 9725
VIRTUAL time: 32h 6min 37s 777ms
REAL time: 2h 7min 32s 224ms
=======================

report.xml, report.md, failures.xml, testclr_details.tar.zst
RISC-V pull_request-FX-QEMU: 0 / 0 (100.00%)
=======================
passed: 0
failed: 0
skipped: 14
killed: 0
------------------------
TOTAL tests: 14
VIRTUAL time: 0ms
REAL time: 4h 30min 0s 477ms
=======================

report.xml, report.md, failures.xml, testclr_details.tar.zst
RISC-V pull_request-FX-VF2: 0 / 61 (0.00%)
=======================
passed: 0
failed: 0
skipped: 14
killed: 61
------------------------
TOTAL tests: 75
VIRTUAL time: 1min 14s 744ms
REAL time: 13h 0min 6s 48ms
=======================

report.xml, report.md, failures.xml, testclr_details.tar.zst
Build information and commands
GIT: bd0e79cc0470c7eae53ef67028e7c567c9fb9846

CI: 0dd2da79b21e6d27378407c3af1305973fd300aa

REPO: dotnet/runtime

BRANCH: main

CONFIG: Checked

LIB_CONFIG: Release
@tomeksowi
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No regressions. Quite a bit of post-bringup cruft went out the window.
Diffs are based on 104,367 contexts (2,270 MinOpts, 102,097 FullOpts).
MISSED contexts: 2 (0.00%)
Overall (-9,469,872 bytes)
CollectionBase size (bytes)Diff size (bytes)PerfScore in Diffs
linux.riscv64.Checked.3.mch71,889,656-9,469,872-7.46%
MinOpts (-2,342,108 bytes)
CollectionBase size (bytes)Diff size (bytes)PerfScore in Diffs
linux.riscv64.Checked.3.mch16,685,964-2,342,108-7.73%
FullOpts (-7,127,764 bytes)
CollectionBase size (bytes)Diff size (bytes)PerfScore in Diffs
linux.riscv64.Checked.3.mch55,203,692-7,127,764-7.45%
Example diffs
linux.riscv64.Checked.3.mch
-48 (-41.38%) : 53568.dasm - Program:Main():int (FullOpts)
@@ -20,35 +20,23 @@ G_M24375_IG01: ; bbWeight=1, gcrefRegs=0000 {}, byrefRegs=0000 {}, byref,
mv fp, sp
;; size=16 bbWeight=1 PerfScore 9.00
G_M24375_IG02: ; bbWeight=1, gcrefRegs=0000 {}, byrefRegs=0000 {}, byref
- lui t6, 0xD1FFAB1E- addiw t6, t6, 0xD1FFAB1E- slli t6, t6, 13- addi t6, t6, 0xD1FFAB1E- slli t6, t6, 2- ld a0, 0xD1FFAB1E(t6)+ auipc a0, 0xD1FFAB1E+ ld a0, 0xD1FFAB1E(a0)
jalr a0 // <unknown method>
- lui t6, 0xD1FFAB1E- addiw t6, t6, 0xD1FFAB1E- slli t6, t6, 13- addi t6, t6, 0xD1FFAB1E- slli t6, t6, 2- ld a0, 0xD1FFAB1E(t6)+ auipc a0, 0xD1FFAB1E+ ld a0, 0xD1FFAB1E(a0)
jalr a0 // <unknown method>
- lui t6, 0xD1FFAB1E- addiw t6, t6, 0xD1FFAB1E- slli t6, t6, 13- addi t6, t6, 0xD1FFAB1E- slli t6, t6, 2- ld a0, 0xD1FFAB1E(t6)+ auipc a0, 0xD1FFAB1E+ ld a0, 0xD1FFAB1E(a0)
jalr a0 // Test:Ret():int
- ;; size=84 bbWeight=1 PerfScore 30.00+ ;; size=36 bbWeight=1 PerfScore 15.00
G_M24375_IG03: ; bbWeight=1, epilog, nogc, extend
ld ra, 8(sp)
ld fp, 0(sp)
addi sp, sp, 16
ret ;; size=16 bbWeight=1 PerfScore 7.50
-; Total bytes of code 116, prolog size 16, PerfScore 46.50, instruction count 17, allocated bytes for code 116 (MethodHash=d9b8a0c8) for method Program:Main():int (FullOpts)+; Total bytes of code 68, prolog size 16, PerfScore 31.50, instruction count 14, allocated bytes for code 68 (MethodHash=d9b8a0c8) for method Program:Main():int (FullOpts)
; ============================================================
Unwind Info:
@@ -59,7 +47,7 @@ Unwind Info:
E bit : 0
X bit : 0
Vers : 0
- Function Length : 58 (0x0003a) Actual length = 116 (0x000074)+ Function Length : 34 (0x00022) Actual length = 68 (0x000044)
---- Epilog scopes ----
---- Scope 0
Epilog Start Offset : 3523193630 (0xd1ffab1e) Actual offset = 3523193630 (0xd1ffab1e) Offset from main function begin = 3523193630 (0xd1ffab1e)
-32 (-40.00%) : 54962.dasm - ExceptionExtensions:RethrowWithNoStackTraceLoss(System.Exception) (FullOpts)
@@ -21,26 +21,18 @@ G_M64910_IG01: ; bbWeight=0, gcrefRegs=0000 {}, byrefRegs=0000 {}, byref,
;; size=16 bbWeight=0 PerfScore 0.00
G_M64910_IG02: ; bbWeight=0, gcrefRegs=0400 {a0}, byrefRegs=0000 {}, byref
; gcrRegs +[a0]
- lui t6, 0xD1FFAB1E- addiw t6, t6, 0xD1FFAB1E- slli t6, t6, 12- addi t6, t6, 0xD1FFAB1E- slli t6, t6, 3- ld a1, 0xD1FFAB1E(t6)+ auipc a1, 0xD1FFAB1E+ ld a1, 0xD1FFAB1E(a1)
jalr a1 // System.Runtime.ExceptionServices.ExceptionDispatchInfo:Capture(System.Exception):System.Runtime.ExceptionServices.ExceptionDispatchInfo
- lui t6, 0xD1FFAB1E- addiw t6, t6, 0xD1FFAB1E- slli t6, t6, 12- addi t6, t6, 0xD1FFAB1E- slli t6, t6, 3- ld a1, 0xD1FFAB1E(t6)+ auipc a1, 0xD1FFAB1E+ ld a1, 0xD1FFAB1E(a1)
lw zero, 0xD1FFAB1E(a0)
jalr a1 // System.Runtime.ExceptionServices.ExceptionDispatchInfo:Throw():this
; gcrRegs -[a0]
ebreak
- ;; size=64 bbWeight=0 PerfScore 0.00+ ;; size=32 bbWeight=0 PerfScore 0.00-; Total bytes of code 80, prolog size 16, PerfScore 0.00, instruction count 12, allocated bytes for code 80 (MethodHash=95e60271) for method ExceptionExtensions:RethrowWithNoStackTraceLoss(System.Exception) (FullOpts)+; Total bytes of code 48, prolog size 16, PerfScore 0.00, instruction count 10, allocated bytes for code 48 (MethodHash=95e60271) for method ExceptionExtensions:RethrowWithNoStackTraceLoss(System.Exception) (FullOpts)
; ============================================================
Unwind Info:
@@ -51,7 +43,7 @@ Unwind Info:
E bit : 0
X bit : 0
Vers : 0
- Function Length : 40 (0x00028) Actual length = 80 (0x000050)+ Function Length : 24 (0x00018) Actual length = 48 (0x000030)
---- Epilog scopes ----
No epilogs
---- Unwind codes ----
-40 (-38.46%) : 856.dasm - Interop:g__ParentDirectoryExists|7_0(System.String):bool (FullOpts)
@@ -22,25 +22,15 @@ G_M36700_IG01: ; bbWeight=1, gcrefRegs=0000 {}, byrefRegs=0000 {}, byref,
;; size=16 bbWeight=1 PerfScore 9.00
G_M36700_IG02: ; bbWeight=1, gcrefRegs=0400 {a0}, byrefRegs=0000 {}, byref
; gcrRegs +[a0]
- lui t6, 0xD1FFAB1E- addiw t6, t6, 0xD1FFAB1E- slli t6, t6, 13- addi t6, t6, 0xD1FFAB1E- slli t6, t6, 2- ld a1, 0xD1FFAB1E(t6)+ auipc a1, 0xD1FFAB1E+ ld a1, 0xD1FFAB1E(a1)
jalr a1 // System.IO.PathInternal:TrimEndingDirectorySeparator(System.String):System.String
- lui t6, 0xD1FFAB1E- addiw t6, t6, 0xD1FFAB1E- slli t6, t6, 32- srli t6, t6, 18- ld a1, 0xD1FFAB1E(t6)+ auipc a1, 0xD1FFAB1E+ ld a1, 0xD1FFAB1E(a1)
jalr a1 // System.IO.Path:GetDirectoryName(System.String):System.String
- lui t6, 0xD1FFAB1E- addiw t6, t6, 0xD1FFAB1E- slli t6, t6, 32- srli t6, t6, 18- ld a1, 0xD1FFAB1E(t6)- ;; size=72 bbWeight=1 PerfScore 25.00+ auipc a1, 0xD1FFAB1E+ ld a1, 0xD1FFAB1E(a1)+ ;; size=32 bbWeight=1 PerfScore 12.00
G_M36700_IG03: ; bbWeight=1, epilog, nogc, extend
ld ra, 8(sp)
ld fp, 0(sp)
@@ -48,7 +38,7 @@ G_M36700_IG03: ; bbWeight=1, epilog, nogc, extend
jr a1 // System.IO.Directory:Exists(System.String):bool
;; size=16 bbWeight=1 PerfScore 7.50
-; Total bytes of code 104, prolog size 16, PerfScore 41.50, instruction count 16, allocated bytes for code 104 (MethodHash=027470a3) for method Interop:<GetExceptionForIoErrno>g__ParentDirectoryExists|7_0(System.String):bool (FullOpts)+; Total bytes of code 64, prolog size 16, PerfScore 28.50, instruction count 13, allocated bytes for code 64 (MethodHash=027470a3) for method Interop:<GetExceptionForIoErrno>g__ParentDirectoryExists|7_0(System.String):bool (FullOpts)
; ============================================================
Unwind Info:
@@ -59,7 +49,7 @@ Unwind Info:
E bit : 0
X bit : 0
Vers : 0
- Function Length : 52 (0x00034) Actual length = 104 (0x000068)+ Function Length : 32 (0x00020) Actual length = 64 (0x000040)
---- Epilog scopes ----
---- Scope 0
Epilog Start Offset : 3523193630 (0xd1ffab1e) Actual offset = 3523193630 (0xd1ffab1e) Offset from main function begin = 3523193630 (0xd1ffab1e)
+0 (0.00%) : 104032.dasm - Microsoft.Diagnostics.Tracing.TraceEvent:get_FormattedMessage():System.String:this (FullOpts)
@@ -22,6 +22,7 @@ G_M51530_IG01: ; bbWeight=1, gcrefRegs=0000 {}, byrefRegs=0000 {}, byref,
G_M51530_IG02: ; bbWeight=1, gcrefRegs=0400 {a0}, byrefRegs=0000 {}, byref
; gcrRegs +[a0]
mv a1, zero
+ ; gcrRegs +[a1]
ld a2, 0xD1FFAB1E(a0)
ld a2, 0xD1FFAB1E(a2)
ld a2, 0xD1FFAB1E(a2)
+0 (0.00%) : 57024.dasm - UDivConst:U8_Div_3(ulong):ulong (FullOpts)
No diffs found?
+0 (0.00%) : 56976.dasm - SlowPathELTTests.SlowPathELTHelpers:MixedSseStructFunc():SlowPathELTTests.MixedSseStruct (FullOpts)
No diffs found?
Details
Size improvements/regressions per collection
CollectionContexts with diffsImprovementsRegressionsSame sizeImprovements (bytes)Regressions (bytes)
linux.riscv64.Checked.3.mch78,13976,85401,285-9,469,872+0
PerfScore improvements/regressions per collection
CollectionContexts with diffsImprovementsRegressionsSame PerfScoreImprovements (PerfScore)Regressions (PerfScore)PerfScore Overall in FullOpts
linux.riscv64.Checked.3.mch78,13957,537020,602-9.99%0.00%-5.6031%
Context information
CollectionDiffed contextsMinOptsFullOptsMissed, baseMissed, diff
linux.riscv64.Checked.3.mch104,3672,270102,0972 (0.00%)2 (0.00%)
jit-analyze output
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+0 (0.00%) : 104032.dasm - Microsoft.Diagnostics.Tracing.TraceEvent:get_FormattedMessage():System.String:this (FullOpts)
@@ -22,6 +22,7 @@ G_M51530_IG01: ; bbWeight=1, gcrefRegs=0000 {}, byrefRegs=0000 {}, byref,
G_M51530_IG02: ; bbWeight=1, gcrefRegs=0400 {a0}, byrefRegs=0000 {}, byref
; gcrRegs +[a0]
mv a1, zero
+ ; gcrRegs +[a1]
ld a2, 0xD1FFAB1E(a0)
ld a2, 0xD1FFAB1E(a2)
ld a2, 0xD1FFAB1E(a2)
Looks like a bonus fix. Notice how this code I removed also silently stripped GC flags.
runtime/src/coreclr/jit/codegenriscv64.cpp

Lines 902 to 905
in
f1cbe0f
if (!compiler->opts.compReloc) 
 { 
 size = EA_SIZE(size); // Strip any Reloc flags from size if we aren't doing relocs.
 } 
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September 2, 2025 06:23
@JulieLeeMSFT
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Oct 6, 2025

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We will review .NET 11 PRs when we are done with .NET 10 last minute works and less busy. Please give us a few more weeks.

CC @jakobbotsch.
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Oct 21, 2025

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@EgorBo Do we need a fix for arm64 version of the code @tomeksowi points at above?
runtime/src/coreclr/jit/codegenarm64.cpp

Lines 2098 to 2101
in
25e088f
if (!compiler->opts.compReloc) 
 { 
 size = EA_SIZE(size); // Strip any Reloc flags from size if we aren't doing relocs
 } 
For address 0 it is clearly not a problem -- would it be a problem for frozen objects?
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If an address can be synthesized as PC-relative (2 instructions: auipc + ld/addi), do so.
Note that it's generally impossible to know where the code will be located, so you can only do this heuristically. How do you recover when you get it wrong?
For x64 we recover the situation by disabling rip-relative addressing globally the first time it happens, and then designing things so that it very rarely happens. Look for m_fAllowRel32.
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@EgorBo Do we need a fix for arm64 version of the code @tomeksowi points at above?
Do you mean it may strip the GC related flags for frozen objects? I think we don't report them to GC anyway, do we?
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Oct 22, 2025

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Note that it's generally impossible to know where the code will be located, so you can only do this heuristically. How do you recover when you get it wrong?
For x64 we recover the situation by disabling rip-relative addressing globally the first time it happens, and then designing things so that it very rarely happens. Look for m_fAllowRel32.
I don't recover, the address of a handle with function address was always within range, but you're right, IsIconHandle(GTF_ICON_FTN_ADDR) is just a heuristic. I remember looking at m_fAllowRel32 briefly but abandoned it because it seemed linked to jump stubs which RISC-V doesn't use (and aren't applicable here since we're doing loads for the handles).
I'll try to use it, maybe communicating failure with m_fJumpStubOverflow = TRUE to reuse existing codepaths, then eeGetRelocTypeHint on the handle value should tell me which way to go.
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For x64 there is a contract between the JIT and VM about when and how relative addressing is used: for data addresses PC-relative addressing can only be used based on getRelocTypeHint. For code addresses PC-relative addressing can always be used, and the VM will create jump stubs if necessary.
If you are using PC-relative addressing for data addresses then I expect you need to build a similar system. If you are only using it for code addresses, then I expect you need to support some form of jump stubs.
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@EgorBo Do we need a fix for arm64 version of the code @tomeksowi points at above?
Do you mean it may strip the GC related flags for frozen objects? I think we don't report them to GC anyway, do we?
Yes, that's what I meant. I was not sure if they GC refs to frozen objects need to be reported or not. If not then it seems ok.
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@EgorBo Do we need a fix for arm64 version of the code @tomeksowi points at above?
Do you mean it may strip the GC related flags for frozen objects? I think we don't report them to GC anyway, do we?
Yes, that's what I meant. I was not sure if they GC refs to frozen objects need to be reported or not. If not then it seems ok.
I think in fact we do report them today, but don't have to
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For linux-musl-riscv64
Comment threadsrc/coreclr/vm/jitinterface.cpp
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@tomeksowi@am11
fix musl build
80a6998
Co-authored-by: Adeel Mujahid <3840695+am11@users.noreply.github.com>
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lower bool
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November 25, 2025 10:42
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@tomeksowi
Merge branch 'main' into pc-rel-pointers
abacec7
Conflicts:
src/coreclr/inc/corinfo.h
src/coreclr/jit/emitriscv64.cpp
src/coreclr/tools/Common/JitInterface/CorInfoImpl.cs
src/coreclr/tools/superpmi/superpmi-shared/compileresult.cpp
src/coreclr/vm/jitinterface.cpp
@tomeksowi
Fix build
8c081a6
@tomeksowi
Fix types and format
e5ce631
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VM side LGTM.
@dotnet/jit-contrib Could you please review the JIT side?
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[RISC-V] Fix too many arguments build error in emitIns_R_AI (#122555)
46de0c9
Fixes#122553, regression after #119203.
Part of #84834, cc @dotnet/samsung
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[RISC-V] Synthesizing PC-relative pointer constants - #119203
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tomeksowi:pc-rel-pointers
Dec 1, 2025
Merged
[RISC-V] Synthesizing PC-relative pointer constants#119203
jakobbotsch merged 43 commits into
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RISC-V is ill-equipped to synthesize large >32-bit constants like absolute pointers, it results in a 6-8 instruction sequence. If an address can be synthesized as PC-relative (2 instructions: auipc + ld/addi), do so. It also simplifies codegen.
Part of #84834, cc @dotnet/samsung
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RISC-V pull_request-CLR-QEMU: 9108 / 9139 (99.66%)
=======================
passed: 9108
failed: 3
skipped: 586
killed: 28
------------------------
TOTAL tests: 9725
VIRTUAL time: 80h 13min 42s 134ms
REAL time: 1h 18min 35s 828ms
=======================

report.xml, report.md, failures.xml, testclr_details.tar.zst
RISC-V pull_request-CLR-VF2: 9108 / 9139 (99.66%)
=======================
passed: 9108
failed: 3
skipped: 586
killed: 28
------------------------
TOTAL tests: 9725
VIRTUAL time: 32h 6min 37s 777ms
REAL time: 2h 7min 32s 224ms
=======================

report.xml, report.md, failures.xml, testclr_details.tar.zst
RISC-V pull_request-FX-QEMU: 0 / 0 (100.00%)
=======================
passed: 0
failed: 0
skipped: 14
killed: 0
------------------------
TOTAL tests: 14
VIRTUAL time: 0ms
REAL time: 4h 30min 0s 477ms
=======================

report.xml, report.md, failures.xml, testclr_details.tar.zst
RISC-V pull_request-FX-VF2: 0 / 61 (0.00%)
=======================
passed: 0
failed: 0
skipped: 14
killed: 61
------------------------
TOTAL tests: 75
VIRTUAL time: 1min 14s 744ms
REAL time: 13h 0min 6s 48ms
=======================

report.xml, report.md, failures.xml, testclr_details.tar.zst
Build information and commands
GIT: bd0e79cc0470c7eae53ef67028e7c567c9fb9846

CI: 0dd2da79b21e6d27378407c3af1305973fd300aa

REPO: dotnet/runtime

BRANCH: main

CONFIG: Checked

LIB_CONFIG: Release
@tomeksowi
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Sep 1, 2025

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No regressions. Quite a bit of post-bringup cruft went out the window.
Diffs are based on 104,367 contexts (2,270 MinOpts, 102,097 FullOpts).
MISSED contexts: 2 (0.00%)
Overall (-9,469,872 bytes)
CollectionBase size (bytes)Diff size (bytes)PerfScore in Diffs
linux.riscv64.Checked.3.mch71,889,656-9,469,872-7.46%
MinOpts (-2,342,108 bytes)
CollectionBase size (bytes)Diff size (bytes)PerfScore in Diffs
linux.riscv64.Checked.3.mch16,685,964-2,342,108-7.73%
FullOpts (-7,127,764 bytes)
CollectionBase size (bytes)Diff size (bytes)PerfScore in Diffs
linux.riscv64.Checked.3.mch55,203,692-7,127,764-7.45%
Example diffs
linux.riscv64.Checked.3.mch
-48 (-41.38%) : 53568.dasm - Program:Main():int (FullOpts)
@@ -20,35 +20,23 @@ G_M24375_IG01: ; bbWeight=1, gcrefRegs=0000 {}, byrefRegs=0000 {}, byref,
mv fp, sp
;; size=16 bbWeight=1 PerfScore 9.00
G_M24375_IG02: ; bbWeight=1, gcrefRegs=0000 {}, byrefRegs=0000 {}, byref
- lui t6, 0xD1FFAB1E- addiw t6, t6, 0xD1FFAB1E- slli t6, t6, 13- addi t6, t6, 0xD1FFAB1E- slli t6, t6, 2- ld a0, 0xD1FFAB1E(t6)+ auipc a0, 0xD1FFAB1E+ ld a0, 0xD1FFAB1E(a0)
jalr a0 // <unknown method>
- lui t6, 0xD1FFAB1E- addiw t6, t6, 0xD1FFAB1E- slli t6, t6, 13- addi t6, t6, 0xD1FFAB1E- slli t6, t6, 2- ld a0, 0xD1FFAB1E(t6)+ auipc a0, 0xD1FFAB1E+ ld a0, 0xD1FFAB1E(a0)
jalr a0 // <unknown method>
- lui t6, 0xD1FFAB1E- addiw t6, t6, 0xD1FFAB1E- slli t6, t6, 13- addi t6, t6, 0xD1FFAB1E- slli t6, t6, 2- ld a0, 0xD1FFAB1E(t6)+ auipc a0, 0xD1FFAB1E+ ld a0, 0xD1FFAB1E(a0)
jalr a0 // Test:Ret():int
- ;; size=84 bbWeight=1 PerfScore 30.00+ ;; size=36 bbWeight=1 PerfScore 15.00
G_M24375_IG03: ; bbWeight=1, epilog, nogc, extend
ld ra, 8(sp)
ld fp, 0(sp)
addi sp, sp, 16
ret ;; size=16 bbWeight=1 PerfScore 7.50
-; Total bytes of code 116, prolog size 16, PerfScore 46.50, instruction count 17, allocated bytes for code 116 (MethodHash=d9b8a0c8) for method Program:Main():int (FullOpts)+; Total bytes of code 68, prolog size 16, PerfScore 31.50, instruction count 14, allocated bytes for code 68 (MethodHash=d9b8a0c8) for method Program:Main():int (FullOpts)
; ============================================================
Unwind Info:
@@ -59,7 +47,7 @@ Unwind Info:
E bit : 0
X bit : 0
Vers : 0
- Function Length : 58 (0x0003a) Actual length = 116 (0x000074)+ Function Length : 34 (0x00022) Actual length = 68 (0x000044)
---- Epilog scopes ----
---- Scope 0
Epilog Start Offset : 3523193630 (0xd1ffab1e) Actual offset = 3523193630 (0xd1ffab1e) Offset from main function begin = 3523193630 (0xd1ffab1e)
-32 (-40.00%) : 54962.dasm - ExceptionExtensions:RethrowWithNoStackTraceLoss(System.Exception) (FullOpts)
@@ -21,26 +21,18 @@ G_M64910_IG01: ; bbWeight=0, gcrefRegs=0000 {}, byrefRegs=0000 {}, byref,
;; size=16 bbWeight=0 PerfScore 0.00
G_M64910_IG02: ; bbWeight=0, gcrefRegs=0400 {a0}, byrefRegs=0000 {}, byref
; gcrRegs +[a0]
- lui t6, 0xD1FFAB1E- addiw t6, t6, 0xD1FFAB1E- slli t6, t6, 12- addi t6, t6, 0xD1FFAB1E- slli t6, t6, 3- ld a1, 0xD1FFAB1E(t6)+ auipc a1, 0xD1FFAB1E+ ld a1, 0xD1FFAB1E(a1)
jalr a1 // System.Runtime.ExceptionServices.ExceptionDispatchInfo:Capture(System.Exception):System.Runtime.ExceptionServices.ExceptionDispatchInfo
- lui t6, 0xD1FFAB1E- addiw t6, t6, 0xD1FFAB1E- slli t6, t6, 12- addi t6, t6, 0xD1FFAB1E- slli t6, t6, 3- ld a1, 0xD1FFAB1E(t6)+ auipc a1, 0xD1FFAB1E+ ld a1, 0xD1FFAB1E(a1)
lw zero, 0xD1FFAB1E(a0)
jalr a1 // System.Runtime.ExceptionServices.ExceptionDispatchInfo:Throw():this
; gcrRegs -[a0]
ebreak
- ;; size=64 bbWeight=0 PerfScore 0.00+ ;; size=32 bbWeight=0 PerfScore 0.00-; Total bytes of code 80, prolog size 16, PerfScore 0.00, instruction count 12, allocated bytes for code 80 (MethodHash=95e60271) for method ExceptionExtensions:RethrowWithNoStackTraceLoss(System.Exception) (FullOpts)+; Total bytes of code 48, prolog size 16, PerfScore 0.00, instruction count 10, allocated bytes for code 48 (MethodHash=95e60271) for method ExceptionExtensions:RethrowWithNoStackTraceLoss(System.Exception) (FullOpts)
; ============================================================
Unwind Info:
@@ -51,7 +43,7 @@ Unwind Info:
E bit : 0
X bit : 0
Vers : 0
- Function Length : 40 (0x00028) Actual length = 80 (0x000050)+ Function Length : 24 (0x00018) Actual length = 48 (0x000030)
---- Epilog scopes ----
No epilogs
---- Unwind codes ----
-40 (-38.46%) : 856.dasm - Interop:g__ParentDirectoryExists|7_0(System.String):bool (FullOpts)
@@ -22,25 +22,15 @@ G_M36700_IG01: ; bbWeight=1, gcrefRegs=0000 {}, byrefRegs=0000 {}, byref,
;; size=16 bbWeight=1 PerfScore 9.00
G_M36700_IG02: ; bbWeight=1, gcrefRegs=0400 {a0}, byrefRegs=0000 {}, byref
; gcrRegs +[a0]
- lui t6, 0xD1FFAB1E- addiw t6, t6, 0xD1FFAB1E- slli t6, t6, 13- addi t6, t6, 0xD1FFAB1E- slli t6, t6, 2- ld a1, 0xD1FFAB1E(t6)+ auipc a1, 0xD1FFAB1E+ ld a1, 0xD1FFAB1E(a1)
jalr a1 // System.IO.PathInternal:TrimEndingDirectorySeparator(System.String):System.String
- lui t6, 0xD1FFAB1E- addiw t6, t6, 0xD1FFAB1E- slli t6, t6, 32- srli t6, t6, 18- ld a1, 0xD1FFAB1E(t6)+ auipc a1, 0xD1FFAB1E+ ld a1, 0xD1FFAB1E(a1)
jalr a1 // System.IO.Path:GetDirectoryName(System.String):System.String
- lui t6, 0xD1FFAB1E- addiw t6, t6, 0xD1FFAB1E- slli t6, t6, 32- srli t6, t6, 18- ld a1, 0xD1FFAB1E(t6)- ;; size=72 bbWeight=1 PerfScore 25.00+ auipc a1, 0xD1FFAB1E+ ld a1, 0xD1FFAB1E(a1)+ ;; size=32 bbWeight=1 PerfScore 12.00
G_M36700_IG03: ; bbWeight=1, epilog, nogc, extend
ld ra, 8(sp)
ld fp, 0(sp)
@@ -48,7 +38,7 @@ G_M36700_IG03: ; bbWeight=1, epilog, nogc, extend
jr a1 // System.IO.Directory:Exists(System.String):bool
;; size=16 bbWeight=1 PerfScore 7.50
-; Total bytes of code 104, prolog size 16, PerfScore 41.50, instruction count 16, allocated bytes for code 104 (MethodHash=027470a3) for method Interop:<GetExceptionForIoErrno>g__ParentDirectoryExists|7_0(System.String):bool (FullOpts)+; Total bytes of code 64, prolog size 16, PerfScore 28.50, instruction count 13, allocated bytes for code 64 (MethodHash=027470a3) for method Interop:<GetExceptionForIoErrno>g__ParentDirectoryExists|7_0(System.String):bool (FullOpts)
; ============================================================
Unwind Info:
@@ -59,7 +49,7 @@ Unwind Info:
E bit : 0
X bit : 0
Vers : 0
- Function Length : 52 (0x00034) Actual length = 104 (0x000068)+ Function Length : 32 (0x00020) Actual length = 64 (0x000040)
---- Epilog scopes ----
---- Scope 0
Epilog Start Offset : 3523193630 (0xd1ffab1e) Actual offset = 3523193630 (0xd1ffab1e) Offset from main function begin = 3523193630 (0xd1ffab1e)
+0 (0.00%) : 104032.dasm - Microsoft.Diagnostics.Tracing.TraceEvent:get_FormattedMessage():System.String:this (FullOpts)
@@ -22,6 +22,7 @@ G_M51530_IG01: ; bbWeight=1, gcrefRegs=0000 {}, byrefRegs=0000 {}, byref,
G_M51530_IG02: ; bbWeight=1, gcrefRegs=0400 {a0}, byrefRegs=0000 {}, byref
; gcrRegs +[a0]
mv a1, zero
+ ; gcrRegs +[a1]
ld a2, 0xD1FFAB1E(a0)
ld a2, 0xD1FFAB1E(a2)
ld a2, 0xD1FFAB1E(a2)
+0 (0.00%) : 57024.dasm - UDivConst:U8_Div_3(ulong):ulong (FullOpts)
No diffs found?
+0 (0.00%) : 56976.dasm - SlowPathELTTests.SlowPathELTHelpers:MixedSseStructFunc():SlowPathELTTests.MixedSseStruct (FullOpts)
No diffs found?
Details
Size improvements/regressions per collection
CollectionContexts with diffsImprovementsRegressionsSame sizeImprovements (bytes)Regressions (bytes)
linux.riscv64.Checked.3.mch78,13976,85401,285-9,469,872+0
PerfScore improvements/regressions per collection
CollectionContexts with diffsImprovementsRegressionsSame PerfScoreImprovements (PerfScore)Regressions (PerfScore)PerfScore Overall in FullOpts
linux.riscv64.Checked.3.mch78,13957,537020,602-9.99%0.00%-5.6031%
Context information
CollectionDiffed contextsMinOptsFullOptsMissed, baseMissed, diff
linux.riscv64.Checked.3.mch104,3672,270102,0972 (0.00%)2 (0.00%)
jit-analyze output
@tomeksowi
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+0 (0.00%) : 104032.dasm - Microsoft.Diagnostics.Tracing.TraceEvent:get_FormattedMessage():System.String:this (FullOpts)
@@ -22,6 +22,7 @@ G_M51530_IG01: ; bbWeight=1, gcrefRegs=0000 {}, byrefRegs=0000 {}, byref,
G_M51530_IG02: ; bbWeight=1, gcrefRegs=0400 {a0}, byrefRegs=0000 {}, byref
; gcrRegs +[a0]
mv a1, zero
+ ; gcrRegs +[a1]
ld a2, 0xD1FFAB1E(a0)
ld a2, 0xD1FFAB1E(a2)
ld a2, 0xD1FFAB1E(a2)
Looks like a bonus fix. Notice how this code I removed also silently stripped GC flags.
runtime/src/coreclr/jit/codegenriscv64.cpp

Lines 902 to 905
in
f1cbe0f
if (!compiler->opts.compReloc) 
 { 
 size = EA_SIZE(size); // Strip any Reloc flags from size if we aren't doing relocs.
 } 
@tomeksowi
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marked this pull request as ready for review
September 2, 2025 06:23
@JulieLeeMSFT
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Oct 6, 2025

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We will review .NET 11 PRs when we are done with .NET 10 last minute works and less busy. Please give us a few more weeks.

CC @jakobbotsch.
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Oct 6, 2025
@jakobbotsch
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Oct 21, 2025

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@EgorBo Do we need a fix for arm64 version of the code @tomeksowi points at above?
runtime/src/coreclr/jit/codegenarm64.cpp

Lines 2098 to 2101
in
25e088f
if (!compiler->opts.compReloc) 
 { 
 size = EA_SIZE(size); // Strip any Reloc flags from size if we aren't doing relocs
 } 
For address 0 it is clearly not a problem -- would it be a problem for frozen objects?
@jakobbotsch
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Oct 21, 2025

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If an address can be synthesized as PC-relative (2 instructions: auipc + ld/addi), do so.
Note that it's generally impossible to know where the code will be located, so you can only do this heuristically. How do you recover when you get it wrong?
For x64 we recover the situation by disabling rip-relative addressing globally the first time it happens, and then designing things so that it very rarely happens. Look for m_fAllowRel32.
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Oct 21, 2025

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@EgorBo Do we need a fix for arm64 version of the code @tomeksowi points at above?
Do you mean it may strip the GC related flags for frozen objects? I think we don't report them to GC anyway, do we?
@tomeksowi
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Oct 22, 2025

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Note that it's generally impossible to know where the code will be located, so you can only do this heuristically. How do you recover when you get it wrong?
For x64 we recover the situation by disabling rip-relative addressing globally the first time it happens, and then designing things so that it very rarely happens. Look for m_fAllowRel32.
I don't recover, the address of a handle with function address was always within range, but you're right, IsIconHandle(GTF_ICON_FTN_ADDR) is just a heuristic. I remember looking at m_fAllowRel32 briefly but abandoned it because it seemed linked to jump stubs which RISC-V doesn't use (and aren't applicable here since we're doing loads for the handles).
I'll try to use it, maybe communicating failure with m_fJumpStubOverflow = TRUE to reuse existing codepaths, then eeGetRelocTypeHint on the handle value should tell me which way to go.
@jakobbotsch
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For x64 there is a contract between the JIT and VM about when and how relative addressing is used: for data addresses PC-relative addressing can only be used based on getRelocTypeHint. For code addresses PC-relative addressing can always be used, and the VM will create jump stubs if necessary.
If you are using PC-relative addressing for data addresses then I expect you need to build a similar system. If you are only using it for code addresses, then I expect you need to support some form of jump stubs.
@jakobbotsch
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@EgorBo Do we need a fix for arm64 version of the code @tomeksowi points at above?
Do you mean it may strip the GC related flags for frozen objects? I think we don't report them to GC anyway, do we?
Yes, that's what I meant. I was not sure if they GC refs to frozen objects need to be reported or not. If not then it seems ok.
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@EgorBo Do we need a fix for arm64 version of the code @tomeksowi points at above?
Do you mean it may strip the GC related flags for frozen objects? I think we don't report them to GC anyway, do we?
Yes, that's what I meant. I was not sure if they GC refs to frozen objects need to be reported or not. If not then it seems ok.
I think in fact we do report them today, but don't have to
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For linux-musl-riscv64
Comment threadsrc/coreclr/vm/jitinterface.cpp
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@tomeksowi@am11
fix musl build
80a6998
Co-authored-by: Adeel Mujahid <3840695+am11@users.noreply.github.com>
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lower bool
062652b
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November 25, 2025 10:42
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@tomeksowi
Merge branch 'main' into pc-rel-pointers
abacec7
Conflicts:
src/coreclr/inc/corinfo.h
src/coreclr/jit/emitriscv64.cpp
src/coreclr/tools/Common/JitInterface/CorInfoImpl.cs
src/coreclr/tools/superpmi/superpmi-shared/compileresult.cpp
src/coreclr/vm/jitinterface.cpp
@tomeksowi
Fix build
8c081a6
@tomeksowi
Fix types and format
e5ce631
@jkotas
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Nov 27, 2025

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VM side LGTM.
@dotnet/jit-contrib Could you please review the JIT side?
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@tomeksowi
[RISC-V] Fix too many arguments build error in emitIns_R_AI (#122555)
46de0c9
Fixes#122553, regression after #119203.
Part of #84834, cc @dotnet/samsung
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, 'i');
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[RISC-V] Synthesizing PC-relative pointer constants - #119203
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[RISC-V] Synthesizing PC-relative pointer constants#119203
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RISC-V is ill-equipped to synthesize large >32-bit constants like absolute pointers, it results in a 6-8 instruction sequence. If an address can be synthesized as PC-relative (2 instructions: auipc + ld/addi), do so. It also simplifies codegen.
Part of #84834, cc @dotnet/samsung
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RISC-V pull_request-CLR-QEMU: 9108 / 9139 (99.66%)
=======================
passed: 9108
failed: 3
skipped: 586
killed: 28
------------------------
TOTAL tests: 9725
VIRTUAL time: 80h 13min 42s 134ms
REAL time: 1h 18min 35s 828ms
=======================

report.xml, report.md, failures.xml, testclr_details.tar.zst
RISC-V pull_request-CLR-VF2: 9108 / 9139 (99.66%)
=======================
passed: 9108
failed: 3
skipped: 586
killed: 28
------------------------
TOTAL tests: 9725
VIRTUAL time: 32h 6min 37s 777ms
REAL time: 2h 7min 32s 224ms
=======================

report.xml, report.md, failures.xml, testclr_details.tar.zst
RISC-V pull_request-FX-QEMU: 0 / 0 (100.00%)
=======================
passed: 0
failed: 0
skipped: 14
killed: 0
------------------------
TOTAL tests: 14
VIRTUAL time: 0ms
REAL time: 4h 30min 0s 477ms
=======================

report.xml, report.md, failures.xml, testclr_details.tar.zst
RISC-V pull_request-FX-VF2: 0 / 61 (0.00%)
=======================
passed: 0
failed: 0
skipped: 14
killed: 61
------------------------
TOTAL tests: 75
VIRTUAL time: 1min 14s 744ms
REAL time: 13h 0min 6s 48ms
=======================

report.xml, report.md, failures.xml, testclr_details.tar.zst
Build information and commands
GIT: bd0e79cc0470c7eae53ef67028e7c567c9fb9846

CI: 0dd2da79b21e6d27378407c3af1305973fd300aa

REPO: dotnet/runtime

BRANCH: main

CONFIG: Checked

LIB_CONFIG: Release
@tomeksowi
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Sep 1, 2025

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No regressions. Quite a bit of post-bringup cruft went out the window.
Diffs are based on 104,367 contexts (2,270 MinOpts, 102,097 FullOpts).
MISSED contexts: 2 (0.00%)
Overall (-9,469,872 bytes)
CollectionBase size (bytes)Diff size (bytes)PerfScore in Diffs
linux.riscv64.Checked.3.mch71,889,656-9,469,872-7.46%
MinOpts (-2,342,108 bytes)
CollectionBase size (bytes)Diff size (bytes)PerfScore in Diffs
linux.riscv64.Checked.3.mch16,685,964-2,342,108-7.73%
FullOpts (-7,127,764 bytes)
CollectionBase size (bytes)Diff size (bytes)PerfScore in Diffs
linux.riscv64.Checked.3.mch55,203,692-7,127,764-7.45%
Example diffs
linux.riscv64.Checked.3.mch
-48 (-41.38%) : 53568.dasm - Program:Main():int (FullOpts)
@@ -20,35 +20,23 @@ G_M24375_IG01: ; bbWeight=1, gcrefRegs=0000 {}, byrefRegs=0000 {}, byref,
mv fp, sp
;; size=16 bbWeight=1 PerfScore 9.00
G_M24375_IG02: ; bbWeight=1, gcrefRegs=0000 {}, byrefRegs=0000 {}, byref
- lui t6, 0xD1FFAB1E- addiw t6, t6, 0xD1FFAB1E- slli t6, t6, 13- addi t6, t6, 0xD1FFAB1E- slli t6, t6, 2- ld a0, 0xD1FFAB1E(t6)+ auipc a0, 0xD1FFAB1E+ ld a0, 0xD1FFAB1E(a0)
jalr a0 // <unknown method>
- lui t6, 0xD1FFAB1E- addiw t6, t6, 0xD1FFAB1E- slli t6, t6, 13- addi t6, t6, 0xD1FFAB1E- slli t6, t6, 2- ld a0, 0xD1FFAB1E(t6)+ auipc a0, 0xD1FFAB1E+ ld a0, 0xD1FFAB1E(a0)
jalr a0 // <unknown method>
- lui t6, 0xD1FFAB1E- addiw t6, t6, 0xD1FFAB1E- slli t6, t6, 13- addi t6, t6, 0xD1FFAB1E- slli t6, t6, 2- ld a0, 0xD1FFAB1E(t6)+ auipc a0, 0xD1FFAB1E+ ld a0, 0xD1FFAB1E(a0)
jalr a0 // Test:Ret():int
- ;; size=84 bbWeight=1 PerfScore 30.00+ ;; size=36 bbWeight=1 PerfScore 15.00
G_M24375_IG03: ; bbWeight=1, epilog, nogc, extend
ld ra, 8(sp)
ld fp, 0(sp)
addi sp, sp, 16
ret ;; size=16 bbWeight=1 PerfScore 7.50
-; Total bytes of code 116, prolog size 16, PerfScore 46.50, instruction count 17, allocated bytes for code 116 (MethodHash=d9b8a0c8) for method Program:Main():int (FullOpts)+; Total bytes of code 68, prolog size 16, PerfScore 31.50, instruction count 14, allocated bytes for code 68 (MethodHash=d9b8a0c8) for method Program:Main():int (FullOpts)
; ============================================================
Unwind Info:
@@ -59,7 +47,7 @@ Unwind Info:
E bit : 0
X bit : 0
Vers : 0
- Function Length : 58 (0x0003a) Actual length = 116 (0x000074)+ Function Length : 34 (0x00022) Actual length = 68 (0x000044)
---- Epilog scopes ----
---- Scope 0
Epilog Start Offset : 3523193630 (0xd1ffab1e) Actual offset = 3523193630 (0xd1ffab1e) Offset from main function begin = 3523193630 (0xd1ffab1e)
-32 (-40.00%) : 54962.dasm - ExceptionExtensions:RethrowWithNoStackTraceLoss(System.Exception) (FullOpts)
@@ -21,26 +21,18 @@ G_M64910_IG01: ; bbWeight=0, gcrefRegs=0000 {}, byrefRegs=0000 {}, byref,
;; size=16 bbWeight=0 PerfScore 0.00
G_M64910_IG02: ; bbWeight=0, gcrefRegs=0400 {a0}, byrefRegs=0000 {}, byref
; gcrRegs +[a0]
- lui t6, 0xD1FFAB1E- addiw t6, t6, 0xD1FFAB1E- slli t6, t6, 12- addi t6, t6, 0xD1FFAB1E- slli t6, t6, 3- ld a1, 0xD1FFAB1E(t6)+ auipc a1, 0xD1FFAB1E+ ld a1, 0xD1FFAB1E(a1)
jalr a1 // System.Runtime.ExceptionServices.ExceptionDispatchInfo:Capture(System.Exception):System.Runtime.ExceptionServices.ExceptionDispatchInfo
- lui t6, 0xD1FFAB1E- addiw t6, t6, 0xD1FFAB1E- slli t6, t6, 12- addi t6, t6, 0xD1FFAB1E- slli t6, t6, 3- ld a1, 0xD1FFAB1E(t6)+ auipc a1, 0xD1FFAB1E+ ld a1, 0xD1FFAB1E(a1)
lw zero, 0xD1FFAB1E(a0)
jalr a1 // System.Runtime.ExceptionServices.ExceptionDispatchInfo:Throw():this
; gcrRegs -[a0]
ebreak
- ;; size=64 bbWeight=0 PerfScore 0.00+ ;; size=32 bbWeight=0 PerfScore 0.00-; Total bytes of code 80, prolog size 16, PerfScore 0.00, instruction count 12, allocated bytes for code 80 (MethodHash=95e60271) for method ExceptionExtensions:RethrowWithNoStackTraceLoss(System.Exception) (FullOpts)+; Total bytes of code 48, prolog size 16, PerfScore 0.00, instruction count 10, allocated bytes for code 48 (MethodHash=95e60271) for method ExceptionExtensions:RethrowWithNoStackTraceLoss(System.Exception) (FullOpts)
; ============================================================
Unwind Info:
@@ -51,7 +43,7 @@ Unwind Info:
E bit : 0
X bit : 0
Vers : 0
- Function Length : 40 (0x00028) Actual length = 80 (0x000050)+ Function Length : 24 (0x00018) Actual length = 48 (0x000030)
---- Epilog scopes ----
No epilogs
---- Unwind codes ----
-40 (-38.46%) : 856.dasm - Interop:g__ParentDirectoryExists|7_0(System.String):bool (FullOpts)
@@ -22,25 +22,15 @@ G_M36700_IG01: ; bbWeight=1, gcrefRegs=0000 {}, byrefRegs=0000 {}, byref,
;; size=16 bbWeight=1 PerfScore 9.00
G_M36700_IG02: ; bbWeight=1, gcrefRegs=0400 {a0}, byrefRegs=0000 {}, byref
; gcrRegs +[a0]
- lui t6, 0xD1FFAB1E- addiw t6, t6, 0xD1FFAB1E- slli t6, t6, 13- addi t6, t6, 0xD1FFAB1E- slli t6, t6, 2- ld a1, 0xD1FFAB1E(t6)+ auipc a1, 0xD1FFAB1E+ ld a1, 0xD1FFAB1E(a1)
jalr a1 // System.IO.PathInternal:TrimEndingDirectorySeparator(System.String):System.String
- lui t6, 0xD1FFAB1E- addiw t6, t6, 0xD1FFAB1E- slli t6, t6, 32- srli t6, t6, 18- ld a1, 0xD1FFAB1E(t6)+ auipc a1, 0xD1FFAB1E+ ld a1, 0xD1FFAB1E(a1)
jalr a1 // System.IO.Path:GetDirectoryName(System.String):System.String
- lui t6, 0xD1FFAB1E- addiw t6, t6, 0xD1FFAB1E- slli t6, t6, 32- srli t6, t6, 18- ld a1, 0xD1FFAB1E(t6)- ;; size=72 bbWeight=1 PerfScore 25.00+ auipc a1, 0xD1FFAB1E+ ld a1, 0xD1FFAB1E(a1)+ ;; size=32 bbWeight=1 PerfScore 12.00
G_M36700_IG03: ; bbWeight=1, epilog, nogc, extend
ld ra, 8(sp)
ld fp, 0(sp)
@@ -48,7 +38,7 @@ G_M36700_IG03: ; bbWeight=1, epilog, nogc, extend
jr a1 // System.IO.Directory:Exists(System.String):bool
;; size=16 bbWeight=1 PerfScore 7.50
-; Total bytes of code 104, prolog size 16, PerfScore 41.50, instruction count 16, allocated bytes for code 104 (MethodHash=027470a3) for method Interop:<GetExceptionForIoErrno>g__ParentDirectoryExists|7_0(System.String):bool (FullOpts)+; Total bytes of code 64, prolog size 16, PerfScore 28.50, instruction count 13, allocated bytes for code 64 (MethodHash=027470a3) for method Interop:<GetExceptionForIoErrno>g__ParentDirectoryExists|7_0(System.String):bool (FullOpts)
; ============================================================
Unwind Info:
@@ -59,7 +49,7 @@ Unwind Info:
E bit : 0
X bit : 0
Vers : 0
- Function Length : 52 (0x00034) Actual length = 104 (0x000068)+ Function Length : 32 (0x00020) Actual length = 64 (0x000040)
---- Epilog scopes ----
---- Scope 0
Epilog Start Offset : 3523193630 (0xd1ffab1e) Actual offset = 3523193630 (0xd1ffab1e) Offset from main function begin = 3523193630 (0xd1ffab1e)
+0 (0.00%) : 104032.dasm - Microsoft.Diagnostics.Tracing.TraceEvent:get_FormattedMessage():System.String:this (FullOpts)
@@ -22,6 +22,7 @@ G_M51530_IG01: ; bbWeight=1, gcrefRegs=0000 {}, byrefRegs=0000 {}, byref,
G_M51530_IG02: ; bbWeight=1, gcrefRegs=0400 {a0}, byrefRegs=0000 {}, byref
; gcrRegs +[a0]
mv a1, zero
+ ; gcrRegs +[a1]
ld a2, 0xD1FFAB1E(a0)
ld a2, 0xD1FFAB1E(a2)
ld a2, 0xD1FFAB1E(a2)
+0 (0.00%) : 57024.dasm - UDivConst:U8_Div_3(ulong):ulong (FullOpts)
No diffs found?
+0 (0.00%) : 56976.dasm - SlowPathELTTests.SlowPathELTHelpers:MixedSseStructFunc():SlowPathELTTests.MixedSseStruct (FullOpts)
No diffs found?
Details
Size improvements/regressions per collection
CollectionContexts with diffsImprovementsRegressionsSame sizeImprovements (bytes)Regressions (bytes)
linux.riscv64.Checked.3.mch78,13976,85401,285-9,469,872+0
PerfScore improvements/regressions per collection
CollectionContexts with diffsImprovementsRegressionsSame PerfScoreImprovements (PerfScore)Regressions (PerfScore)PerfScore Overall in FullOpts
linux.riscv64.Checked.3.mch78,13957,537020,602-9.99%0.00%-5.6031%
Context information
CollectionDiffed contextsMinOptsFullOptsMissed, baseMissed, diff
linux.riscv64.Checked.3.mch104,3672,270102,0972 (0.00%)2 (0.00%)
jit-analyze output
@tomeksowi
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+0 (0.00%) : 104032.dasm - Microsoft.Diagnostics.Tracing.TraceEvent:get_FormattedMessage():System.String:this (FullOpts)
@@ -22,6 +22,7 @@ G_M51530_IG01: ; bbWeight=1, gcrefRegs=0000 {}, byrefRegs=0000 {}, byref,
G_M51530_IG02: ; bbWeight=1, gcrefRegs=0400 {a0}, byrefRegs=0000 {}, byref
; gcrRegs +[a0]
mv a1, zero
+ ; gcrRegs +[a1]
ld a2, 0xD1FFAB1E(a0)
ld a2, 0xD1FFAB1E(a2)
ld a2, 0xD1FFAB1E(a2)
Looks like a bonus fix. Notice how this code I removed also silently stripped GC flags.
runtime/src/coreclr/jit/codegenriscv64.cpp

Lines 902 to 905
in
f1cbe0f
if (!compiler->opts.compReloc) 
 { 
 size = EA_SIZE(size); // Strip any Reloc flags from size if we aren't doing relocs.
 } 
@tomeksowi
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marked this pull request as ready for review
September 2, 2025 06:23
@JulieLeeMSFT
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Oct 6, 2025

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We will review .NET 11 PRs when we are done with .NET 10 last minute works and less busy. Please give us a few more weeks.

CC @jakobbotsch.
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added this to the 11.0.0 milestone
Oct 6, 2025
@jakobbotsch
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Oct 21, 2025

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@EgorBo Do we need a fix for arm64 version of the code @tomeksowi points at above?
runtime/src/coreclr/jit/codegenarm64.cpp

Lines 2098 to 2101
in
25e088f
if (!compiler->opts.compReloc) 
 { 
 size = EA_SIZE(size); // Strip any Reloc flags from size if we aren't doing relocs
 } 
For address 0 it is clearly not a problem -- would it be a problem for frozen objects?
@jakobbotsch
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Oct 21, 2025

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If an address can be synthesized as PC-relative (2 instructions: auipc + ld/addi), do so.
Note that it's generally impossible to know where the code will be located, so you can only do this heuristically. How do you recover when you get it wrong?
For x64 we recover the situation by disabling rip-relative addressing globally the first time it happens, and then designing things so that it very rarely happens. Look for m_fAllowRel32.
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Oct 21, 2025

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@EgorBo Do we need a fix for arm64 version of the code @tomeksowi points at above?
Do you mean it may strip the GC related flags for frozen objects? I think we don't report them to GC anyway, do we?
@tomeksowi
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Oct 22, 2025

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Note that it's generally impossible to know where the code will be located, so you can only do this heuristically. How do you recover when you get it wrong?
For x64 we recover the situation by disabling rip-relative addressing globally the first time it happens, and then designing things so that it very rarely happens. Look for m_fAllowRel32.
I don't recover, the address of a handle with function address was always within range, but you're right, IsIconHandle(GTF_ICON_FTN_ADDR) is just a heuristic. I remember looking at m_fAllowRel32 briefly but abandoned it because it seemed linked to jump stubs which RISC-V doesn't use (and aren't applicable here since we're doing loads for the handles).
I'll try to use it, maybe communicating failure with m_fJumpStubOverflow = TRUE to reuse existing codepaths, then eeGetRelocTypeHint on the handle value should tell me which way to go.
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For x64 there is a contract between the JIT and VM about when and how relative addressing is used: for data addresses PC-relative addressing can only be used based on getRelocTypeHint. For code addresses PC-relative addressing can always be used, and the VM will create jump stubs if necessary.
If you are using PC-relative addressing for data addresses then I expect you need to build a similar system. If you are only using it for code addresses, then I expect you need to support some form of jump stubs.
@jakobbotsch
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@EgorBo Do we need a fix for arm64 version of the code @tomeksowi points at above?
Do you mean it may strip the GC related flags for frozen objects? I think we don't report them to GC anyway, do we?
Yes, that's what I meant. I was not sure if they GC refs to frozen objects need to be reported or not. If not then it seems ok.
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@EgorBo Do we need a fix for arm64 version of the code @tomeksowi points at above?
Do you mean it may strip the GC related flags for frozen objects? I think we don't report them to GC anyway, do we?
Yes, that's what I meant. I was not sure if they GC refs to frozen objects need to be reported or not. If not then it seems ok.
I think in fact we do report them today, but don't have to
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For linux-musl-riscv64
Comment threadsrc/coreclr/vm/jitinterface.cpp
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Comment threadsrc/coreclr/tools/superpmi/superpmi-shared/compileresult.cpp
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November 19, 2025 20:16
@tomeksowi@am11
fix musl build
80a6998
Co-authored-by: Adeel Mujahid <3840695+am11@users.noreply.github.com>
@tomeksowi
lower bool
062652b
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Comment threadsrc/coreclr/tools/Common/Compiler/ObjectWriter/ElfObjectWriter.cs
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@tomeksowi
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marked this pull request as ready for review
November 25, 2025 10:42
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mentioned this pull request
Nov 25, 2025
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@tomeksowi
Merge branch 'main' into pc-rel-pointers
abacec7
Conflicts:
src/coreclr/inc/corinfo.h
src/coreclr/jit/emitriscv64.cpp
src/coreclr/tools/Common/JitInterface/CorInfoImpl.cs
src/coreclr/tools/superpmi/superpmi-shared/compileresult.cpp
src/coreclr/vm/jitinterface.cpp
@tomeksowi
Fix build
8c081a6
@tomeksowi
Fix types and format
e5ce631
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Nov 27, 2025

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VM side LGTM.
@dotnet/jit-contrib Could you please review the JIT side?
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@tomeksowi
[RISC-V] Fix too many arguments build error in emitIns_R_AI (#122555)
46de0c9
Fixes#122553, regression after #119203.
Part of #84834, cc @dotnet/samsung
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@tomeksowi@risc-vv@JulieLeeMSFT@jakobbotsch@EgorBo@jkotas@kg@am11@steveisok@clamp03

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Strip utm_, fbclid, gclid, etc. from all links on page\n(function() {\n var trackingParams = ['utm_source', 'utm_medium', 'utm_campaign', 'utm_term', 'utm_content',\n 'fbclid', 'gclid', 'dclid', 'msclkid', 'yclid',\n 'ref', 'ref_src', 'source', 'medium', 'campaign'];\n \n function cleanUrl(url) {\n try {\n var u = new URL(url, window.location.origin);\n var changed = false;\n trackingParams.forEach(function(p) {\n if (u.searchParams.has(p)) {\n u.searchParams.delete(p);\n changed = true;\n }\n });\n return changed ? u.toString() : url;\n } catch (e) {\n return url;\n }\n }\n \n function cleanLinks() {\n document.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n \n cleanLinks();\n \n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1) {\n if (node.tagName === 'A') cleanLinks();\n node.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Remove Tracking Parameters from Links");
}
} catch(__e) { console.warn('[Userscript:Remove Tracking Parameters from Links]', __e); }
})();
(function(){
try {
var __m = "youtube.com";
var __re = new RegExp('^' + "youtube\\.com" + '

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[RISC-V] Synthesizing PC-relative pointer constants - #119203
Merged
jakobbotsch merged 43 commits into
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tomeksowi:pc-rel-pointers
Dec 1, 2025
Merged
[RISC-V] Synthesizing PC-relative pointer constants#119203
jakobbotsch merged 43 commits into
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tomeksowi:pc-rel-pointers
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RISC-V is ill-equipped to synthesize large >32-bit constants like absolute pointers, it results in a 6-8 instruction sequence. If an address can be synthesized as PC-relative (2 instructions: auipc + ld/addi), do so. It also simplifies codegen.
Part of #84834, cc @dotnet/samsung
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RISC-V pull_request-CLR-QEMU: 9108 / 9139 (99.66%)
=======================
passed: 9108
failed: 3
skipped: 586
killed: 28
------------------------
TOTAL tests: 9725
VIRTUAL time: 80h 13min 42s 134ms
REAL time: 1h 18min 35s 828ms
=======================

report.xml, report.md, failures.xml, testclr_details.tar.zst
RISC-V pull_request-CLR-VF2: 9108 / 9139 (99.66%)
=======================
passed: 9108
failed: 3
skipped: 586
killed: 28
------------------------
TOTAL tests: 9725
VIRTUAL time: 32h 6min 37s 777ms
REAL time: 2h 7min 32s 224ms
=======================

report.xml, report.md, failures.xml, testclr_details.tar.zst
RISC-V pull_request-FX-QEMU: 0 / 0 (100.00%)
=======================
passed: 0
failed: 0
skipped: 14
killed: 0
------------------------
TOTAL tests: 14
VIRTUAL time: 0ms
REAL time: 4h 30min 0s 477ms
=======================

report.xml, report.md, failures.xml, testclr_details.tar.zst
RISC-V pull_request-FX-VF2: 0 / 61 (0.00%)
=======================
passed: 0
failed: 0
skipped: 14
killed: 61
------------------------
TOTAL tests: 75
VIRTUAL time: 1min 14s 744ms
REAL time: 13h 0min 6s 48ms
=======================

report.xml, report.md, failures.xml, testclr_details.tar.zst
Build information and commands
GIT: bd0e79cc0470c7eae53ef67028e7c567c9fb9846

CI: 0dd2da79b21e6d27378407c3af1305973fd300aa

REPO: dotnet/runtime

BRANCH: main

CONFIG: Checked

LIB_CONFIG: Release
@tomeksowi
tomeksowi
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Sep 1, 2025

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No regressions. Quite a bit of post-bringup cruft went out the window.
Diffs are based on 104,367 contexts (2,270 MinOpts, 102,097 FullOpts).
MISSED contexts: 2 (0.00%)
Overall (-9,469,872 bytes)
CollectionBase size (bytes)Diff size (bytes)PerfScore in Diffs
linux.riscv64.Checked.3.mch71,889,656-9,469,872-7.46%
MinOpts (-2,342,108 bytes)
CollectionBase size (bytes)Diff size (bytes)PerfScore in Diffs
linux.riscv64.Checked.3.mch16,685,964-2,342,108-7.73%
FullOpts (-7,127,764 bytes)
CollectionBase size (bytes)Diff size (bytes)PerfScore in Diffs
linux.riscv64.Checked.3.mch55,203,692-7,127,764-7.45%
Example diffs
linux.riscv64.Checked.3.mch
-48 (-41.38%) : 53568.dasm - Program:Main():int (FullOpts)
@@ -20,35 +20,23 @@ G_M24375_IG01: ; bbWeight=1, gcrefRegs=0000 {}, byrefRegs=0000 {}, byref,
mv fp, sp
;; size=16 bbWeight=1 PerfScore 9.00
G_M24375_IG02: ; bbWeight=1, gcrefRegs=0000 {}, byrefRegs=0000 {}, byref
- lui t6, 0xD1FFAB1E- addiw t6, t6, 0xD1FFAB1E- slli t6, t6, 13- addi t6, t6, 0xD1FFAB1E- slli t6, t6, 2- ld a0, 0xD1FFAB1E(t6)+ auipc a0, 0xD1FFAB1E+ ld a0, 0xD1FFAB1E(a0)
jalr a0 // <unknown method>
- lui t6, 0xD1FFAB1E- addiw t6, t6, 0xD1FFAB1E- slli t6, t6, 13- addi t6, t6, 0xD1FFAB1E- slli t6, t6, 2- ld a0, 0xD1FFAB1E(t6)+ auipc a0, 0xD1FFAB1E+ ld a0, 0xD1FFAB1E(a0)
jalr a0 // <unknown method>
- lui t6, 0xD1FFAB1E- addiw t6, t6, 0xD1FFAB1E- slli t6, t6, 13- addi t6, t6, 0xD1FFAB1E- slli t6, t6, 2- ld a0, 0xD1FFAB1E(t6)+ auipc a0, 0xD1FFAB1E+ ld a0, 0xD1FFAB1E(a0)
jalr a0 // Test:Ret():int
- ;; size=84 bbWeight=1 PerfScore 30.00+ ;; size=36 bbWeight=1 PerfScore 15.00
G_M24375_IG03: ; bbWeight=1, epilog, nogc, extend
ld ra, 8(sp)
ld fp, 0(sp)
addi sp, sp, 16
ret ;; size=16 bbWeight=1 PerfScore 7.50
-; Total bytes of code 116, prolog size 16, PerfScore 46.50, instruction count 17, allocated bytes for code 116 (MethodHash=d9b8a0c8) for method Program:Main():int (FullOpts)+; Total bytes of code 68, prolog size 16, PerfScore 31.50, instruction count 14, allocated bytes for code 68 (MethodHash=d9b8a0c8) for method Program:Main():int (FullOpts)
; ============================================================
Unwind Info:
@@ -59,7 +47,7 @@ Unwind Info:
E bit : 0
X bit : 0
Vers : 0
- Function Length : 58 (0x0003a) Actual length = 116 (0x000074)+ Function Length : 34 (0x00022) Actual length = 68 (0x000044)
---- Epilog scopes ----
---- Scope 0
Epilog Start Offset : 3523193630 (0xd1ffab1e) Actual offset = 3523193630 (0xd1ffab1e) Offset from main function begin = 3523193630 (0xd1ffab1e)
-32 (-40.00%) : 54962.dasm - ExceptionExtensions:RethrowWithNoStackTraceLoss(System.Exception) (FullOpts)
@@ -21,26 +21,18 @@ G_M64910_IG01: ; bbWeight=0, gcrefRegs=0000 {}, byrefRegs=0000 {}, byref,
;; size=16 bbWeight=0 PerfScore 0.00
G_M64910_IG02: ; bbWeight=0, gcrefRegs=0400 {a0}, byrefRegs=0000 {}, byref
; gcrRegs +[a0]
- lui t6, 0xD1FFAB1E- addiw t6, t6, 0xD1FFAB1E- slli t6, t6, 12- addi t6, t6, 0xD1FFAB1E- slli t6, t6, 3- ld a1, 0xD1FFAB1E(t6)+ auipc a1, 0xD1FFAB1E+ ld a1, 0xD1FFAB1E(a1)
jalr a1 // System.Runtime.ExceptionServices.ExceptionDispatchInfo:Capture(System.Exception):System.Runtime.ExceptionServices.ExceptionDispatchInfo
- lui t6, 0xD1FFAB1E- addiw t6, t6, 0xD1FFAB1E- slli t6, t6, 12- addi t6, t6, 0xD1FFAB1E- slli t6, t6, 3- ld a1, 0xD1FFAB1E(t6)+ auipc a1, 0xD1FFAB1E+ ld a1, 0xD1FFAB1E(a1)
lw zero, 0xD1FFAB1E(a0)
jalr a1 // System.Runtime.ExceptionServices.ExceptionDispatchInfo:Throw():this
; gcrRegs -[a0]
ebreak
- ;; size=64 bbWeight=0 PerfScore 0.00+ ;; size=32 bbWeight=0 PerfScore 0.00-; Total bytes of code 80, prolog size 16, PerfScore 0.00, instruction count 12, allocated bytes for code 80 (MethodHash=95e60271) for method ExceptionExtensions:RethrowWithNoStackTraceLoss(System.Exception) (FullOpts)+; Total bytes of code 48, prolog size 16, PerfScore 0.00, instruction count 10, allocated bytes for code 48 (MethodHash=95e60271) for method ExceptionExtensions:RethrowWithNoStackTraceLoss(System.Exception) (FullOpts)
; ============================================================
Unwind Info:
@@ -51,7 +43,7 @@ Unwind Info:
E bit : 0
X bit : 0
Vers : 0
- Function Length : 40 (0x00028) Actual length = 80 (0x000050)+ Function Length : 24 (0x00018) Actual length = 48 (0x000030)
---- Epilog scopes ----
No epilogs
---- Unwind codes ----
-40 (-38.46%) : 856.dasm - Interop:g__ParentDirectoryExists|7_0(System.String):bool (FullOpts)
@@ -22,25 +22,15 @@ G_M36700_IG01: ; bbWeight=1, gcrefRegs=0000 {}, byrefRegs=0000 {}, byref,
;; size=16 bbWeight=1 PerfScore 9.00
G_M36700_IG02: ; bbWeight=1, gcrefRegs=0400 {a0}, byrefRegs=0000 {}, byref
; gcrRegs +[a0]
- lui t6, 0xD1FFAB1E- addiw t6, t6, 0xD1FFAB1E- slli t6, t6, 13- addi t6, t6, 0xD1FFAB1E- slli t6, t6, 2- ld a1, 0xD1FFAB1E(t6)+ auipc a1, 0xD1FFAB1E+ ld a1, 0xD1FFAB1E(a1)
jalr a1 // System.IO.PathInternal:TrimEndingDirectorySeparator(System.String):System.String
- lui t6, 0xD1FFAB1E- addiw t6, t6, 0xD1FFAB1E- slli t6, t6, 32- srli t6, t6, 18- ld a1, 0xD1FFAB1E(t6)+ auipc a1, 0xD1FFAB1E+ ld a1, 0xD1FFAB1E(a1)
jalr a1 // System.IO.Path:GetDirectoryName(System.String):System.String
- lui t6, 0xD1FFAB1E- addiw t6, t6, 0xD1FFAB1E- slli t6, t6, 32- srli t6, t6, 18- ld a1, 0xD1FFAB1E(t6)- ;; size=72 bbWeight=1 PerfScore 25.00+ auipc a1, 0xD1FFAB1E+ ld a1, 0xD1FFAB1E(a1)+ ;; size=32 bbWeight=1 PerfScore 12.00
G_M36700_IG03: ; bbWeight=1, epilog, nogc, extend
ld ra, 8(sp)
ld fp, 0(sp)
@@ -48,7 +38,7 @@ G_M36700_IG03: ; bbWeight=1, epilog, nogc, extend
jr a1 // System.IO.Directory:Exists(System.String):bool
;; size=16 bbWeight=1 PerfScore 7.50
-; Total bytes of code 104, prolog size 16, PerfScore 41.50, instruction count 16, allocated bytes for code 104 (MethodHash=027470a3) for method Interop:<GetExceptionForIoErrno>g__ParentDirectoryExists|7_0(System.String):bool (FullOpts)+; Total bytes of code 64, prolog size 16, PerfScore 28.50, instruction count 13, allocated bytes for code 64 (MethodHash=027470a3) for method Interop:<GetExceptionForIoErrno>g__ParentDirectoryExists|7_0(System.String):bool (FullOpts)
; ============================================================
Unwind Info:
@@ -59,7 +49,7 @@ Unwind Info:
E bit : 0
X bit : 0
Vers : 0
- Function Length : 52 (0x00034) Actual length = 104 (0x000068)+ Function Length : 32 (0x00020) Actual length = 64 (0x000040)
---- Epilog scopes ----
---- Scope 0
Epilog Start Offset : 3523193630 (0xd1ffab1e) Actual offset = 3523193630 (0xd1ffab1e) Offset from main function begin = 3523193630 (0xd1ffab1e)
+0 (0.00%) : 104032.dasm - Microsoft.Diagnostics.Tracing.TraceEvent:get_FormattedMessage():System.String:this (FullOpts)
@@ -22,6 +22,7 @@ G_M51530_IG01: ; bbWeight=1, gcrefRegs=0000 {}, byrefRegs=0000 {}, byref,
G_M51530_IG02: ; bbWeight=1, gcrefRegs=0400 {a0}, byrefRegs=0000 {}, byref
; gcrRegs +[a0]
mv a1, zero
+ ; gcrRegs +[a1]
ld a2, 0xD1FFAB1E(a0)
ld a2, 0xD1FFAB1E(a2)
ld a2, 0xD1FFAB1E(a2)
+0 (0.00%) : 57024.dasm - UDivConst:U8_Div_3(ulong):ulong (FullOpts)
No diffs found?
+0 (0.00%) : 56976.dasm - SlowPathELTTests.SlowPathELTHelpers:MixedSseStructFunc():SlowPathELTTests.MixedSseStruct (FullOpts)
No diffs found?
Details
Size improvements/regressions per collection
CollectionContexts with diffsImprovementsRegressionsSame sizeImprovements (bytes)Regressions (bytes)
linux.riscv64.Checked.3.mch78,13976,85401,285-9,469,872+0
PerfScore improvements/regressions per collection
CollectionContexts with diffsImprovementsRegressionsSame PerfScoreImprovements (PerfScore)Regressions (PerfScore)PerfScore Overall in FullOpts
linux.riscv64.Checked.3.mch78,13957,537020,602-9.99%0.00%-5.6031%
Context information
CollectionDiffed contextsMinOptsFullOptsMissed, baseMissed, diff
linux.riscv64.Checked.3.mch104,3672,270102,0972 (0.00%)2 (0.00%)
jit-analyze output
@tomeksowi
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+0 (0.00%) : 104032.dasm - Microsoft.Diagnostics.Tracing.TraceEvent:get_FormattedMessage():System.String:this (FullOpts)
@@ -22,6 +22,7 @@ G_M51530_IG01: ; bbWeight=1, gcrefRegs=0000 {}, byrefRegs=0000 {}, byref,
G_M51530_IG02: ; bbWeight=1, gcrefRegs=0400 {a0}, byrefRegs=0000 {}, byref
; gcrRegs +[a0]
mv a1, zero
+ ; gcrRegs +[a1]
ld a2, 0xD1FFAB1E(a0)
ld a2, 0xD1FFAB1E(a2)
ld a2, 0xD1FFAB1E(a2)
Looks like a bonus fix. Notice how this code I removed also silently stripped GC flags.
runtime/src/coreclr/jit/codegenriscv64.cpp

Lines 902 to 905
in
f1cbe0f
if (!compiler->opts.compReloc) 
 { 
 size = EA_SIZE(size); // Strip any Reloc flags from size if we aren't doing relocs.
 } 
@tomeksowi
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marked this pull request as ready for review
September 2, 2025 06:23
@JulieLeeMSFT
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Oct 6, 2025

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We will review .NET 11 PRs when we are done with .NET 10 last minute works and less busy. Please give us a few more weeks.

CC @jakobbotsch.
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added this to the 11.0.0 milestone
Oct 6, 2025
@jakobbotsch
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Oct 21, 2025

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@EgorBo Do we need a fix for arm64 version of the code @tomeksowi points at above?
runtime/src/coreclr/jit/codegenarm64.cpp

Lines 2098 to 2101
in
25e088f
if (!compiler->opts.compReloc) 
 { 
 size = EA_SIZE(size); // Strip any Reloc flags from size if we aren't doing relocs
 } 
For address 0 it is clearly not a problem -- would it be a problem for frozen objects?
@jakobbotsch
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Oct 21, 2025

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If an address can be synthesized as PC-relative (2 instructions: auipc + ld/addi), do so.
Note that it's generally impossible to know where the code will be located, so you can only do this heuristically. How do you recover when you get it wrong?
For x64 we recover the situation by disabling rip-relative addressing globally the first time it happens, and then designing things so that it very rarely happens. Look for m_fAllowRel32.
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Oct 21, 2025

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@EgorBo Do we need a fix for arm64 version of the code @tomeksowi points at above?
Do you mean it may strip the GC related flags for frozen objects? I think we don't report them to GC anyway, do we?
@tomeksowi
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Oct 22, 2025

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Note that it's generally impossible to know where the code will be located, so you can only do this heuristically. How do you recover when you get it wrong?
For x64 we recover the situation by disabling rip-relative addressing globally the first time it happens, and then designing things so that it very rarely happens. Look for m_fAllowRel32.
I don't recover, the address of a handle with function address was always within range, but you're right, IsIconHandle(GTF_ICON_FTN_ADDR) is just a heuristic. I remember looking at m_fAllowRel32 briefly but abandoned it because it seemed linked to jump stubs which RISC-V doesn't use (and aren't applicable here since we're doing loads for the handles).
I'll try to use it, maybe communicating failure with m_fJumpStubOverflow = TRUE to reuse existing codepaths, then eeGetRelocTypeHint on the handle value should tell me which way to go.
@jakobbotsch
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For x64 there is a contract between the JIT and VM about when and how relative addressing is used: for data addresses PC-relative addressing can only be used based on getRelocTypeHint. For code addresses PC-relative addressing can always be used, and the VM will create jump stubs if necessary.
If you are using PC-relative addressing for data addresses then I expect you need to build a similar system. If you are only using it for code addresses, then I expect you need to support some form of jump stubs.
@jakobbotsch
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@EgorBo Do we need a fix for arm64 version of the code @tomeksowi points at above?
Do you mean it may strip the GC related flags for frozen objects? I think we don't report them to GC anyway, do we?
Yes, that's what I meant. I was not sure if they GC refs to frozen objects need to be reported or not. If not then it seems ok.
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@EgorBo Do we need a fix for arm64 version of the code @tomeksowi points at above?
Do you mean it may strip the GC related flags for frozen objects? I think we don't report them to GC anyway, do we?
Yes, that's what I meant. I was not sure if they GC refs to frozen objects need to be reported or not. If not then it seems ok.
I think in fact we do report them today, but don't have to
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For linux-musl-riscv64
Comment threadsrc/coreclr/vm/jitinterface.cpp
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@tomeksowi@am11
fix musl build
80a6998
Co-authored-by: Adeel Mujahid <3840695+am11@users.noreply.github.com>
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lower bool
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@tomeksowi
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marked this pull request as ready for review
November 25, 2025 10:42
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@tomeksowi
Merge branch 'main' into pc-rel-pointers
abacec7
Conflicts:
src/coreclr/inc/corinfo.h
src/coreclr/jit/emitriscv64.cpp
src/coreclr/tools/Common/JitInterface/CorInfoImpl.cs
src/coreclr/tools/superpmi/superpmi-shared/compileresult.cpp
src/coreclr/vm/jitinterface.cpp
@tomeksowi
Fix build
8c081a6
@tomeksowi
Fix types and format
e5ce631
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VM side LGTM.
@dotnet/jit-contrib Could you please review the JIT side?
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[RISC-V] Fix too many arguments build error in emitIns_R_AI (#122555)
46de0c9
Fixes#122553, regression after #119203.
Part of #84834, cc @dotnet/samsung
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, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Auto-enable theater mode on YouTube\n(function() {\n function tryTheater() {\n var btn = document.querySelector('button[aria-label=\"Theater mode\"], ytd-player #player button[title=\"Theater mode\"]');\n if (btn && !btn.classList.contains('activated')) {\n btn.click();\n }\n }\n \n // Try immediately\n tryTheater();\n \n // Try after navigation (SPA)\n var lastUrl = location.href;\n setInterval(function() {\n if (location.href !== lastUrl) {\n lastUrl = location.href;\n setTimeout(tryTheater, 500);\n }\n }, 1000);\n \n // Also try on player load\n var observer = new MutationObserver(tryTheater);\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "YouTube Theater Mode Default");
}
} catch(__e) { console.warn('[Userscript:YouTube Theater Mode Default]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

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[RISC-V] Synthesizing PC-relative pointer constants - #119203
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[RISC-V] Synthesizing PC-relative pointer constants#119203
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RISC-V is ill-equipped to synthesize large >32-bit constants like absolute pointers, it results in a 6-8 instruction sequence. If an address can be synthesized as PC-relative (2 instructions: auipc + ld/addi), do so. It also simplifies codegen.
Part of #84834, cc @dotnet/samsung
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RISC-V pull_request-CLR-QEMU: 9108 / 9139 (99.66%)
=======================
passed: 9108
failed: 3
skipped: 586
killed: 28
------------------------
TOTAL tests: 9725
VIRTUAL time: 80h 13min 42s 134ms
REAL time: 1h 18min 35s 828ms
=======================

report.xml, report.md, failures.xml, testclr_details.tar.zst
RISC-V pull_request-CLR-VF2: 9108 / 9139 (99.66%)
=======================
passed: 9108
failed: 3
skipped: 586
killed: 28
------------------------
TOTAL tests: 9725
VIRTUAL time: 32h 6min 37s 777ms
REAL time: 2h 7min 32s 224ms
=======================

report.xml, report.md, failures.xml, testclr_details.tar.zst
RISC-V pull_request-FX-QEMU: 0 / 0 (100.00%)
=======================
passed: 0
failed: 0
skipped: 14
killed: 0
------------------------
TOTAL tests: 14
VIRTUAL time: 0ms
REAL time: 4h 30min 0s 477ms
=======================

report.xml, report.md, failures.xml, testclr_details.tar.zst
RISC-V pull_request-FX-VF2: 0 / 61 (0.00%)
=======================
passed: 0
failed: 0
skipped: 14
killed: 61
------------------------
TOTAL tests: 75
VIRTUAL time: 1min 14s 744ms
REAL time: 13h 0min 6s 48ms
=======================

report.xml, report.md, failures.xml, testclr_details.tar.zst
Build information and commands
GIT: bd0e79cc0470c7eae53ef67028e7c567c9fb9846

CI: 0dd2da79b21e6d27378407c3af1305973fd300aa

REPO: dotnet/runtime

BRANCH: main

CONFIG: Checked

LIB_CONFIG: Release
@tomeksowi
tomeksowi
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Sep 1, 2025

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No regressions. Quite a bit of post-bringup cruft went out the window.
Diffs are based on 104,367 contexts (2,270 MinOpts, 102,097 FullOpts).
MISSED contexts: 2 (0.00%)
Overall (-9,469,872 bytes)
CollectionBase size (bytes)Diff size (bytes)PerfScore in Diffs
linux.riscv64.Checked.3.mch71,889,656-9,469,872-7.46%
MinOpts (-2,342,108 bytes)
CollectionBase size (bytes)Diff size (bytes)PerfScore in Diffs
linux.riscv64.Checked.3.mch16,685,964-2,342,108-7.73%
FullOpts (-7,127,764 bytes)
CollectionBase size (bytes)Diff size (bytes)PerfScore in Diffs
linux.riscv64.Checked.3.mch55,203,692-7,127,764-7.45%
Example diffs
linux.riscv64.Checked.3.mch
-48 (-41.38%) : 53568.dasm - Program:Main():int (FullOpts)
@@ -20,35 +20,23 @@ G_M24375_IG01: ; bbWeight=1, gcrefRegs=0000 {}, byrefRegs=0000 {}, byref,
mv fp, sp
;; size=16 bbWeight=1 PerfScore 9.00
G_M24375_IG02: ; bbWeight=1, gcrefRegs=0000 {}, byrefRegs=0000 {}, byref
- lui t6, 0xD1FFAB1E- addiw t6, t6, 0xD1FFAB1E- slli t6, t6, 13- addi t6, t6, 0xD1FFAB1E- slli t6, t6, 2- ld a0, 0xD1FFAB1E(t6)+ auipc a0, 0xD1FFAB1E+ ld a0, 0xD1FFAB1E(a0)
jalr a0 // <unknown method>
- lui t6, 0xD1FFAB1E- addiw t6, t6, 0xD1FFAB1E- slli t6, t6, 13- addi t6, t6, 0xD1FFAB1E- slli t6, t6, 2- ld a0, 0xD1FFAB1E(t6)+ auipc a0, 0xD1FFAB1E+ ld a0, 0xD1FFAB1E(a0)
jalr a0 // <unknown method>
- lui t6, 0xD1FFAB1E- addiw t6, t6, 0xD1FFAB1E- slli t6, t6, 13- addi t6, t6, 0xD1FFAB1E- slli t6, t6, 2- ld a0, 0xD1FFAB1E(t6)+ auipc a0, 0xD1FFAB1E+ ld a0, 0xD1FFAB1E(a0)
jalr a0 // Test:Ret():int
- ;; size=84 bbWeight=1 PerfScore 30.00+ ;; size=36 bbWeight=1 PerfScore 15.00
G_M24375_IG03: ; bbWeight=1, epilog, nogc, extend
ld ra, 8(sp)
ld fp, 0(sp)
addi sp, sp, 16
ret ;; size=16 bbWeight=1 PerfScore 7.50
-; Total bytes of code 116, prolog size 16, PerfScore 46.50, instruction count 17, allocated bytes for code 116 (MethodHash=d9b8a0c8) for method Program:Main():int (FullOpts)+; Total bytes of code 68, prolog size 16, PerfScore 31.50, instruction count 14, allocated bytes for code 68 (MethodHash=d9b8a0c8) for method Program:Main():int (FullOpts)
; ============================================================
Unwind Info:
@@ -59,7 +47,7 @@ Unwind Info:
E bit : 0
X bit : 0
Vers : 0
- Function Length : 58 (0x0003a) Actual length = 116 (0x000074)+ Function Length : 34 (0x00022) Actual length = 68 (0x000044)
---- Epilog scopes ----
---- Scope 0
Epilog Start Offset : 3523193630 (0xd1ffab1e) Actual offset = 3523193630 (0xd1ffab1e) Offset from main function begin = 3523193630 (0xd1ffab1e)
-32 (-40.00%) : 54962.dasm - ExceptionExtensions:RethrowWithNoStackTraceLoss(System.Exception) (FullOpts)
@@ -21,26 +21,18 @@ G_M64910_IG01: ; bbWeight=0, gcrefRegs=0000 {}, byrefRegs=0000 {}, byref,
;; size=16 bbWeight=0 PerfScore 0.00
G_M64910_IG02: ; bbWeight=0, gcrefRegs=0400 {a0}, byrefRegs=0000 {}, byref
; gcrRegs +[a0]
- lui t6, 0xD1FFAB1E- addiw t6, t6, 0xD1FFAB1E- slli t6, t6, 12- addi t6, t6, 0xD1FFAB1E- slli t6, t6, 3- ld a1, 0xD1FFAB1E(t6)+ auipc a1, 0xD1FFAB1E+ ld a1, 0xD1FFAB1E(a1)
jalr a1 // System.Runtime.ExceptionServices.ExceptionDispatchInfo:Capture(System.Exception):System.Runtime.ExceptionServices.ExceptionDispatchInfo
- lui t6, 0xD1FFAB1E- addiw t6, t6, 0xD1FFAB1E- slli t6, t6, 12- addi t6, t6, 0xD1FFAB1E- slli t6, t6, 3- ld a1, 0xD1FFAB1E(t6)+ auipc a1, 0xD1FFAB1E+ ld a1, 0xD1FFAB1E(a1)
lw zero, 0xD1FFAB1E(a0)
jalr a1 // System.Runtime.ExceptionServices.ExceptionDispatchInfo:Throw():this
; gcrRegs -[a0]
ebreak
- ;; size=64 bbWeight=0 PerfScore 0.00+ ;; size=32 bbWeight=0 PerfScore 0.00-; Total bytes of code 80, prolog size 16, PerfScore 0.00, instruction count 12, allocated bytes for code 80 (MethodHash=95e60271) for method ExceptionExtensions:RethrowWithNoStackTraceLoss(System.Exception) (FullOpts)+; Total bytes of code 48, prolog size 16, PerfScore 0.00, instruction count 10, allocated bytes for code 48 (MethodHash=95e60271) for method ExceptionExtensions:RethrowWithNoStackTraceLoss(System.Exception) (FullOpts)
; ============================================================
Unwind Info:
@@ -51,7 +43,7 @@ Unwind Info:
E bit : 0
X bit : 0
Vers : 0
- Function Length : 40 (0x00028) Actual length = 80 (0x000050)+ Function Length : 24 (0x00018) Actual length = 48 (0x000030)
---- Epilog scopes ----
No epilogs
---- Unwind codes ----
-40 (-38.46%) : 856.dasm - Interop:g__ParentDirectoryExists|7_0(System.String):bool (FullOpts)
@@ -22,25 +22,15 @@ G_M36700_IG01: ; bbWeight=1, gcrefRegs=0000 {}, byrefRegs=0000 {}, byref,
;; size=16 bbWeight=1 PerfScore 9.00
G_M36700_IG02: ; bbWeight=1, gcrefRegs=0400 {a0}, byrefRegs=0000 {}, byref
; gcrRegs +[a0]
- lui t6, 0xD1FFAB1E- addiw t6, t6, 0xD1FFAB1E- slli t6, t6, 13- addi t6, t6, 0xD1FFAB1E- slli t6, t6, 2- ld a1, 0xD1FFAB1E(t6)+ auipc a1, 0xD1FFAB1E+ ld a1, 0xD1FFAB1E(a1)
jalr a1 // System.IO.PathInternal:TrimEndingDirectorySeparator(System.String):System.String
- lui t6, 0xD1FFAB1E- addiw t6, t6, 0xD1FFAB1E- slli t6, t6, 32- srli t6, t6, 18- ld a1, 0xD1FFAB1E(t6)+ auipc a1, 0xD1FFAB1E+ ld a1, 0xD1FFAB1E(a1)
jalr a1 // System.IO.Path:GetDirectoryName(System.String):System.String
- lui t6, 0xD1FFAB1E- addiw t6, t6, 0xD1FFAB1E- slli t6, t6, 32- srli t6, t6, 18- ld a1, 0xD1FFAB1E(t6)- ;; size=72 bbWeight=1 PerfScore 25.00+ auipc a1, 0xD1FFAB1E+ ld a1, 0xD1FFAB1E(a1)+ ;; size=32 bbWeight=1 PerfScore 12.00
G_M36700_IG03: ; bbWeight=1, epilog, nogc, extend
ld ra, 8(sp)
ld fp, 0(sp)
@@ -48,7 +38,7 @@ G_M36700_IG03: ; bbWeight=1, epilog, nogc, extend
jr a1 // System.IO.Directory:Exists(System.String):bool
;; size=16 bbWeight=1 PerfScore 7.50
-; Total bytes of code 104, prolog size 16, PerfScore 41.50, instruction count 16, allocated bytes for code 104 (MethodHash=027470a3) for method Interop:<GetExceptionForIoErrno>g__ParentDirectoryExists|7_0(System.String):bool (FullOpts)+; Total bytes of code 64, prolog size 16, PerfScore 28.50, instruction count 13, allocated bytes for code 64 (MethodHash=027470a3) for method Interop:<GetExceptionForIoErrno>g__ParentDirectoryExists|7_0(System.String):bool (FullOpts)
; ============================================================
Unwind Info:
@@ -59,7 +49,7 @@ Unwind Info:
E bit : 0
X bit : 0
Vers : 0
- Function Length : 52 (0x00034) Actual length = 104 (0x000068)+ Function Length : 32 (0x00020) Actual length = 64 (0x000040)
---- Epilog scopes ----
---- Scope 0
Epilog Start Offset : 3523193630 (0xd1ffab1e) Actual offset = 3523193630 (0xd1ffab1e) Offset from main function begin = 3523193630 (0xd1ffab1e)
+0 (0.00%) : 104032.dasm - Microsoft.Diagnostics.Tracing.TraceEvent:get_FormattedMessage():System.String:this (FullOpts)
@@ -22,6 +22,7 @@ G_M51530_IG01: ; bbWeight=1, gcrefRegs=0000 {}, byrefRegs=0000 {}, byref,
G_M51530_IG02: ; bbWeight=1, gcrefRegs=0400 {a0}, byrefRegs=0000 {}, byref
; gcrRegs +[a0]
mv a1, zero
+ ; gcrRegs +[a1]
ld a2, 0xD1FFAB1E(a0)
ld a2, 0xD1FFAB1E(a2)
ld a2, 0xD1FFAB1E(a2)
+0 (0.00%) : 57024.dasm - UDivConst:U8_Div_3(ulong):ulong (FullOpts)
No diffs found?
+0 (0.00%) : 56976.dasm - SlowPathELTTests.SlowPathELTHelpers:MixedSseStructFunc():SlowPathELTTests.MixedSseStruct (FullOpts)
No diffs found?
Details
Size improvements/regressions per collection
CollectionContexts with diffsImprovementsRegressionsSame sizeImprovements (bytes)Regressions (bytes)
linux.riscv64.Checked.3.mch78,13976,85401,285-9,469,872+0
PerfScore improvements/regressions per collection
CollectionContexts with diffsImprovementsRegressionsSame PerfScoreImprovements (PerfScore)Regressions (PerfScore)PerfScore Overall in FullOpts
linux.riscv64.Checked.3.mch78,13957,537020,602-9.99%0.00%-5.6031%
Context information
CollectionDiffed contextsMinOptsFullOptsMissed, baseMissed, diff
linux.riscv64.Checked.3.mch104,3672,270102,0972 (0.00%)2 (0.00%)
jit-analyze output
@tomeksowi
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+0 (0.00%) : 104032.dasm - Microsoft.Diagnostics.Tracing.TraceEvent:get_FormattedMessage():System.String:this (FullOpts)
@@ -22,6 +22,7 @@ G_M51530_IG01: ; bbWeight=1, gcrefRegs=0000 {}, byrefRegs=0000 {}, byref,
G_M51530_IG02: ; bbWeight=1, gcrefRegs=0400 {a0}, byrefRegs=0000 {}, byref
; gcrRegs +[a0]
mv a1, zero
+ ; gcrRegs +[a1]
ld a2, 0xD1FFAB1E(a0)
ld a2, 0xD1FFAB1E(a2)
ld a2, 0xD1FFAB1E(a2)
Looks like a bonus fix. Notice how this code I removed also silently stripped GC flags.
runtime/src/coreclr/jit/codegenriscv64.cpp

Lines 902 to 905
in
f1cbe0f
if (!compiler->opts.compReloc) 
 { 
 size = EA_SIZE(size); // Strip any Reloc flags from size if we aren't doing relocs.
 } 
@tomeksowi
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marked this pull request as ready for review
September 2, 2025 06:23
@JulieLeeMSFT
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Oct 6, 2025

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We will review .NET 11 PRs when we are done with .NET 10 last minute works and less busy. Please give us a few more weeks.

CC @jakobbotsch.
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added this to the 11.0.0 milestone
Oct 6, 2025
@jakobbotsch
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Oct 21, 2025

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@EgorBo Do we need a fix for arm64 version of the code @tomeksowi points at above?
runtime/src/coreclr/jit/codegenarm64.cpp

Lines 2098 to 2101
in
25e088f
if (!compiler->opts.compReloc) 
 { 
 size = EA_SIZE(size); // Strip any Reloc flags from size if we aren't doing relocs
 } 
For address 0 it is clearly not a problem -- would it be a problem for frozen objects?
@jakobbotsch
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Oct 21, 2025

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If an address can be synthesized as PC-relative (2 instructions: auipc + ld/addi), do so.
Note that it's generally impossible to know where the code will be located, so you can only do this heuristically. How do you recover when you get it wrong?
For x64 we recover the situation by disabling rip-relative addressing globally the first time it happens, and then designing things so that it very rarely happens. Look for m_fAllowRel32.
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@EgorBo Do we need a fix for arm64 version of the code @tomeksowi points at above?
Do you mean it may strip the GC related flags for frozen objects? I think we don't report them to GC anyway, do we?
@tomeksowi
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Oct 22, 2025

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Note that it's generally impossible to know where the code will be located, so you can only do this heuristically. How do you recover when you get it wrong?
For x64 we recover the situation by disabling rip-relative addressing globally the first time it happens, and then designing things so that it very rarely happens. Look for m_fAllowRel32.
I don't recover, the address of a handle with function address was always within range, but you're right, IsIconHandle(GTF_ICON_FTN_ADDR) is just a heuristic. I remember looking at m_fAllowRel32 briefly but abandoned it because it seemed linked to jump stubs which RISC-V doesn't use (and aren't applicable here since we're doing loads for the handles).
I'll try to use it, maybe communicating failure with m_fJumpStubOverflow = TRUE to reuse existing codepaths, then eeGetRelocTypeHint on the handle value should tell me which way to go.
@jakobbotsch
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For x64 there is a contract between the JIT and VM about when and how relative addressing is used: for data addresses PC-relative addressing can only be used based on getRelocTypeHint. For code addresses PC-relative addressing can always be used, and the VM will create jump stubs if necessary.
If you are using PC-relative addressing for data addresses then I expect you need to build a similar system. If you are only using it for code addresses, then I expect you need to support some form of jump stubs.
@jakobbotsch
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@EgorBo Do we need a fix for arm64 version of the code @tomeksowi points at above?
Do you mean it may strip the GC related flags for frozen objects? I think we don't report them to GC anyway, do we?
Yes, that's what I meant. I was not sure if they GC refs to frozen objects need to be reported or not. If not then it seems ok.
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@EgorBo Do we need a fix for arm64 version of the code @tomeksowi points at above?
Do you mean it may strip the GC related flags for frozen objects? I think we don't report them to GC anyway, do we?
Yes, that's what I meant. I was not sure if they GC refs to frozen objects need to be reported or not. If not then it seems ok.
I think in fact we do report them today, but don't have to
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For linux-musl-riscv64
Comment threadsrc/coreclr/vm/jitinterface.cpp
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@tomeksowi@am11
fix musl build
80a6998
Co-authored-by: Adeel Mujahid <3840695+am11@users.noreply.github.com>
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lower bool
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marked this pull request as ready for review
November 25, 2025 10:42
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@tomeksowi
Merge branch 'main' into pc-rel-pointers
abacec7
Conflicts:
src/coreclr/inc/corinfo.h
src/coreclr/jit/emitriscv64.cpp
src/coreclr/tools/Common/JitInterface/CorInfoImpl.cs
src/coreclr/tools/superpmi/superpmi-shared/compileresult.cpp
src/coreclr/vm/jitinterface.cpp
@tomeksowi
Fix build
8c081a6
@tomeksowi
Fix types and format
e5ce631
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VM side LGTM.
@dotnet/jit-contrib Could you please review the JIT side?
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[RISC-V] Fix too many arguments build error in emitIns_R_AI (#122555)
46de0c9
Fixes#122553, regression after #119203.
Part of #84834, cc @dotnet/samsung
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if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Remove or un-stick sticky/fixed headers that block content\n(function() {\n function unstick() {\n document.querySelectorAll('header, nav, [role=\"banner\"], .header, .navbar, .sticky, .fixed-top, [style*=\"position: fixed\"], [style*=\"position:sticky\"]').forEach(function(el) {\n if (el.style.position === 'fixed' || el.style.position === 'sticky' || \n getComputedStyle(el).position === 'fixed' || getComputedStyle(el).position === 'sticky') {\n el.style.position = 'static';\n el.style.top = 'auto';\n el.style.zIndex = 'auto';\n }\n });\n }\n \n unstick();\n \n var observer = new MutationObserver(unstick);\n observer.observe(document.body, { childList: true, subtree: true, attributes: true, attributeFilter: ['style', 'class'] });\n})();", "Kill Sticky Headers");
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[RISC-V] Synthesizing PC-relative pointer constants - #119203
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tomeksowi:pc-rel-pointers
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Merged
[RISC-V] Synthesizing PC-relative pointer constants#119203
jakobbotsch merged 43 commits into
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RISC-V is ill-equipped to synthesize large >32-bit constants like absolute pointers, it results in a 6-8 instruction sequence. If an address can be synthesized as PC-relative (2 instructions: auipc + ld/addi), do so. It also simplifies codegen.
Part of #84834, cc @dotnet/samsung
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RISC-V pull_request-CLR-QEMU: 9108 / 9139 (99.66%)
=======================
passed: 9108
failed: 3
skipped: 586
killed: 28
------------------------
TOTAL tests: 9725
VIRTUAL time: 80h 13min 42s 134ms
REAL time: 1h 18min 35s 828ms
=======================

report.xml, report.md, failures.xml, testclr_details.tar.zst
RISC-V pull_request-CLR-VF2: 9108 / 9139 (99.66%)
=======================
passed: 9108
failed: 3
skipped: 586
killed: 28
------------------------
TOTAL tests: 9725
VIRTUAL time: 32h 6min 37s 777ms
REAL time: 2h 7min 32s 224ms
=======================

report.xml, report.md, failures.xml, testclr_details.tar.zst
RISC-V pull_request-FX-QEMU: 0 / 0 (100.00%)
=======================
passed: 0
failed: 0
skipped: 14
killed: 0
------------------------
TOTAL tests: 14
VIRTUAL time: 0ms
REAL time: 4h 30min 0s 477ms
=======================

report.xml, report.md, failures.xml, testclr_details.tar.zst
RISC-V pull_request-FX-VF2: 0 / 61 (0.00%)
=======================
passed: 0
failed: 0
skipped: 14
killed: 61
------------------------
TOTAL tests: 75
VIRTUAL time: 1min 14s 744ms
REAL time: 13h 0min 6s 48ms
=======================

report.xml, report.md, failures.xml, testclr_details.tar.zst
Build information and commands
GIT: bd0e79cc0470c7eae53ef67028e7c567c9fb9846

CI: 0dd2da79b21e6d27378407c3af1305973fd300aa

REPO: dotnet/runtime

BRANCH: main

CONFIG: Checked

LIB_CONFIG: Release
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No regressions. Quite a bit of post-bringup cruft went out the window.
Diffs are based on 104,367 contexts (2,270 MinOpts, 102,097 FullOpts).
MISSED contexts: 2 (0.00%)
Overall (-9,469,872 bytes)
CollectionBase size (bytes)Diff size (bytes)PerfScore in Diffs
linux.riscv64.Checked.3.mch71,889,656-9,469,872-7.46%
MinOpts (-2,342,108 bytes)
CollectionBase size (bytes)Diff size (bytes)PerfScore in Diffs
linux.riscv64.Checked.3.mch16,685,964-2,342,108-7.73%
FullOpts (-7,127,764 bytes)
CollectionBase size (bytes)Diff size (bytes)PerfScore in Diffs
linux.riscv64.Checked.3.mch55,203,692-7,127,764-7.45%
Example diffs
linux.riscv64.Checked.3.mch
-48 (-41.38%) : 53568.dasm - Program:Main():int (FullOpts)
@@ -20,35 +20,23 @@ G_M24375_IG01: ; bbWeight=1, gcrefRegs=0000 {}, byrefRegs=0000 {}, byref,
mv fp, sp
;; size=16 bbWeight=1 PerfScore 9.00
G_M24375_IG02: ; bbWeight=1, gcrefRegs=0000 {}, byrefRegs=0000 {}, byref
- lui t6, 0xD1FFAB1E- addiw t6, t6, 0xD1FFAB1E- slli t6, t6, 13- addi t6, t6, 0xD1FFAB1E- slli t6, t6, 2- ld a0, 0xD1FFAB1E(t6)+ auipc a0, 0xD1FFAB1E+ ld a0, 0xD1FFAB1E(a0)
jalr a0 // <unknown method>
- lui t6, 0xD1FFAB1E- addiw t6, t6, 0xD1FFAB1E- slli t6, t6, 13- addi t6, t6, 0xD1FFAB1E- slli t6, t6, 2- ld a0, 0xD1FFAB1E(t6)+ auipc a0, 0xD1FFAB1E+ ld a0, 0xD1FFAB1E(a0)
jalr a0 // <unknown method>
- lui t6, 0xD1FFAB1E- addiw t6, t6, 0xD1FFAB1E- slli t6, t6, 13- addi t6, t6, 0xD1FFAB1E- slli t6, t6, 2- ld a0, 0xD1FFAB1E(t6)+ auipc a0, 0xD1FFAB1E+ ld a0, 0xD1FFAB1E(a0)
jalr a0 // Test:Ret():int
- ;; size=84 bbWeight=1 PerfScore 30.00+ ;; size=36 bbWeight=1 PerfScore 15.00
G_M24375_IG03: ; bbWeight=1, epilog, nogc, extend
ld ra, 8(sp)
ld fp, 0(sp)
addi sp, sp, 16
ret ;; size=16 bbWeight=1 PerfScore 7.50
-; Total bytes of code 116, prolog size 16, PerfScore 46.50, instruction count 17, allocated bytes for code 116 (MethodHash=d9b8a0c8) for method Program:Main():int (FullOpts)+; Total bytes of code 68, prolog size 16, PerfScore 31.50, instruction count 14, allocated bytes for code 68 (MethodHash=d9b8a0c8) for method Program:Main():int (FullOpts)
; ============================================================
Unwind Info:
@@ -59,7 +47,7 @@ Unwind Info:
E bit : 0
X bit : 0
Vers : 0
- Function Length : 58 (0x0003a) Actual length = 116 (0x000074)+ Function Length : 34 (0x00022) Actual length = 68 (0x000044)
---- Epilog scopes ----
---- Scope 0
Epilog Start Offset : 3523193630 (0xd1ffab1e) Actual offset = 3523193630 (0xd1ffab1e) Offset from main function begin = 3523193630 (0xd1ffab1e)
-32 (-40.00%) : 54962.dasm - ExceptionExtensions:RethrowWithNoStackTraceLoss(System.Exception) (FullOpts)
@@ -21,26 +21,18 @@ G_M64910_IG01: ; bbWeight=0, gcrefRegs=0000 {}, byrefRegs=0000 {}, byref,
;; size=16 bbWeight=0 PerfScore 0.00
G_M64910_IG02: ; bbWeight=0, gcrefRegs=0400 {a0}, byrefRegs=0000 {}, byref
; gcrRegs +[a0]
- lui t6, 0xD1FFAB1E- addiw t6, t6, 0xD1FFAB1E- slli t6, t6, 12- addi t6, t6, 0xD1FFAB1E- slli t6, t6, 3- ld a1, 0xD1FFAB1E(t6)+ auipc a1, 0xD1FFAB1E+ ld a1, 0xD1FFAB1E(a1)
jalr a1 // System.Runtime.ExceptionServices.ExceptionDispatchInfo:Capture(System.Exception):System.Runtime.ExceptionServices.ExceptionDispatchInfo
- lui t6, 0xD1FFAB1E- addiw t6, t6, 0xD1FFAB1E- slli t6, t6, 12- addi t6, t6, 0xD1FFAB1E- slli t6, t6, 3- ld a1, 0xD1FFAB1E(t6)+ auipc a1, 0xD1FFAB1E+ ld a1, 0xD1FFAB1E(a1)
lw zero, 0xD1FFAB1E(a0)
jalr a1 // System.Runtime.ExceptionServices.ExceptionDispatchInfo:Throw():this
; gcrRegs -[a0]
ebreak
- ;; size=64 bbWeight=0 PerfScore 0.00+ ;; size=32 bbWeight=0 PerfScore 0.00-; Total bytes of code 80, prolog size 16, PerfScore 0.00, instruction count 12, allocated bytes for code 80 (MethodHash=95e60271) for method ExceptionExtensions:RethrowWithNoStackTraceLoss(System.Exception) (FullOpts)+; Total bytes of code 48, prolog size 16, PerfScore 0.00, instruction count 10, allocated bytes for code 48 (MethodHash=95e60271) for method ExceptionExtensions:RethrowWithNoStackTraceLoss(System.Exception) (FullOpts)
; ============================================================
Unwind Info:
@@ -51,7 +43,7 @@ Unwind Info:
E bit : 0
X bit : 0
Vers : 0
- Function Length : 40 (0x00028) Actual length = 80 (0x000050)+ Function Length : 24 (0x00018) Actual length = 48 (0x000030)
---- Epilog scopes ----
No epilogs
---- Unwind codes ----
-40 (-38.46%) : 856.dasm - Interop:g__ParentDirectoryExists|7_0(System.String):bool (FullOpts)
@@ -22,25 +22,15 @@ G_M36700_IG01: ; bbWeight=1, gcrefRegs=0000 {}, byrefRegs=0000 {}, byref,
;; size=16 bbWeight=1 PerfScore 9.00
G_M36700_IG02: ; bbWeight=1, gcrefRegs=0400 {a0}, byrefRegs=0000 {}, byref
; gcrRegs +[a0]
- lui t6, 0xD1FFAB1E- addiw t6, t6, 0xD1FFAB1E- slli t6, t6, 13- addi t6, t6, 0xD1FFAB1E- slli t6, t6, 2- ld a1, 0xD1FFAB1E(t6)+ auipc a1, 0xD1FFAB1E+ ld a1, 0xD1FFAB1E(a1)
jalr a1 // System.IO.PathInternal:TrimEndingDirectorySeparator(System.String):System.String
- lui t6, 0xD1FFAB1E- addiw t6, t6, 0xD1FFAB1E- slli t6, t6, 32- srli t6, t6, 18- ld a1, 0xD1FFAB1E(t6)+ auipc a1, 0xD1FFAB1E+ ld a1, 0xD1FFAB1E(a1)
jalr a1 // System.IO.Path:GetDirectoryName(System.String):System.String
- lui t6, 0xD1FFAB1E- addiw t6, t6, 0xD1FFAB1E- slli t6, t6, 32- srli t6, t6, 18- ld a1, 0xD1FFAB1E(t6)- ;; size=72 bbWeight=1 PerfScore 25.00+ auipc a1, 0xD1FFAB1E+ ld a1, 0xD1FFAB1E(a1)+ ;; size=32 bbWeight=1 PerfScore 12.00
G_M36700_IG03: ; bbWeight=1, epilog, nogc, extend
ld ra, 8(sp)
ld fp, 0(sp)
@@ -48,7 +38,7 @@ G_M36700_IG03: ; bbWeight=1, epilog, nogc, extend
jr a1 // System.IO.Directory:Exists(System.String):bool
;; size=16 bbWeight=1 PerfScore 7.50
-; Total bytes of code 104, prolog size 16, PerfScore 41.50, instruction count 16, allocated bytes for code 104 (MethodHash=027470a3) for method Interop:<GetExceptionForIoErrno>g__ParentDirectoryExists|7_0(System.String):bool (FullOpts)+; Total bytes of code 64, prolog size 16, PerfScore 28.50, instruction count 13, allocated bytes for code 64 (MethodHash=027470a3) for method Interop:<GetExceptionForIoErrno>g__ParentDirectoryExists|7_0(System.String):bool (FullOpts)
; ============================================================
Unwind Info:
@@ -59,7 +49,7 @@ Unwind Info:
E bit : 0
X bit : 0
Vers : 0
- Function Length : 52 (0x00034) Actual length = 104 (0x000068)+ Function Length : 32 (0x00020) Actual length = 64 (0x000040)
---- Epilog scopes ----
---- Scope 0
Epilog Start Offset : 3523193630 (0xd1ffab1e) Actual offset = 3523193630 (0xd1ffab1e) Offset from main function begin = 3523193630 (0xd1ffab1e)
+0 (0.00%) : 104032.dasm - Microsoft.Diagnostics.Tracing.TraceEvent:get_FormattedMessage():System.String:this (FullOpts)
@@ -22,6 +22,7 @@ G_M51530_IG01: ; bbWeight=1, gcrefRegs=0000 {}, byrefRegs=0000 {}, byref,
G_M51530_IG02: ; bbWeight=1, gcrefRegs=0400 {a0}, byrefRegs=0000 {}, byref
; gcrRegs +[a0]
mv a1, zero
+ ; gcrRegs +[a1]
ld a2, 0xD1FFAB1E(a0)
ld a2, 0xD1FFAB1E(a2)
ld a2, 0xD1FFAB1E(a2)
+0 (0.00%) : 57024.dasm - UDivConst:U8_Div_3(ulong):ulong (FullOpts)
No diffs found?
+0 (0.00%) : 56976.dasm - SlowPathELTTests.SlowPathELTHelpers:MixedSseStructFunc():SlowPathELTTests.MixedSseStruct (FullOpts)
No diffs found?
Details
Size improvements/regressions per collection
CollectionContexts with diffsImprovementsRegressionsSame sizeImprovements (bytes)Regressions (bytes)
linux.riscv64.Checked.3.mch78,13976,85401,285-9,469,872+0
PerfScore improvements/regressions per collection
CollectionContexts with diffsImprovementsRegressionsSame PerfScoreImprovements (PerfScore)Regressions (PerfScore)PerfScore Overall in FullOpts
linux.riscv64.Checked.3.mch78,13957,537020,602-9.99%0.00%-5.6031%
Context information
CollectionDiffed contextsMinOptsFullOptsMissed, baseMissed, diff
linux.riscv64.Checked.3.mch104,3672,270102,0972 (0.00%)2 (0.00%)
jit-analyze output
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+0 (0.00%) : 104032.dasm - Microsoft.Diagnostics.Tracing.TraceEvent:get_FormattedMessage():System.String:this (FullOpts)
@@ -22,6 +22,7 @@ G_M51530_IG01: ; bbWeight=1, gcrefRegs=0000 {}, byrefRegs=0000 {}, byref,
G_M51530_IG02: ; bbWeight=1, gcrefRegs=0400 {a0}, byrefRegs=0000 {}, byref
; gcrRegs +[a0]
mv a1, zero
+ ; gcrRegs +[a1]
ld a2, 0xD1FFAB1E(a0)
ld a2, 0xD1FFAB1E(a2)
ld a2, 0xD1FFAB1E(a2)
Looks like a bonus fix. Notice how this code I removed also silently stripped GC flags.
runtime/src/coreclr/jit/codegenriscv64.cpp

Lines 902 to 905
in
f1cbe0f
if (!compiler->opts.compReloc) 
 { 
 size = EA_SIZE(size); // Strip any Reloc flags from size if we aren't doing relocs.
 } 
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September 2, 2025 06:23
@JulieLeeMSFT
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Oct 6, 2025

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We will review .NET 11 PRs when we are done with .NET 10 last minute works and less busy. Please give us a few more weeks.

CC @jakobbotsch.
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Oct 21, 2025

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@EgorBo Do we need a fix for arm64 version of the code @tomeksowi points at above?
runtime/src/coreclr/jit/codegenarm64.cpp

Lines 2098 to 2101
in
25e088f
if (!compiler->opts.compReloc) 
 { 
 size = EA_SIZE(size); // Strip any Reloc flags from size if we aren't doing relocs
 } 
For address 0 it is clearly not a problem -- would it be a problem for frozen objects?
@jakobbotsch
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If an address can be synthesized as PC-relative (2 instructions: auipc + ld/addi), do so.
Note that it's generally impossible to know where the code will be located, so you can only do this heuristically. How do you recover when you get it wrong?
For x64 we recover the situation by disabling rip-relative addressing globally the first time it happens, and then designing things so that it very rarely happens. Look for m_fAllowRel32.
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@EgorBo Do we need a fix for arm64 version of the code @tomeksowi points at above?
Do you mean it may strip the GC related flags for frozen objects? I think we don't report them to GC anyway, do we?
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Oct 22, 2025

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Note that it's generally impossible to know where the code will be located, so you can only do this heuristically. How do you recover when you get it wrong?
For x64 we recover the situation by disabling rip-relative addressing globally the first time it happens, and then designing things so that it very rarely happens. Look for m_fAllowRel32.
I don't recover, the address of a handle with function address was always within range, but you're right, IsIconHandle(GTF_ICON_FTN_ADDR) is just a heuristic. I remember looking at m_fAllowRel32 briefly but abandoned it because it seemed linked to jump stubs which RISC-V doesn't use (and aren't applicable here since we're doing loads for the handles).
I'll try to use it, maybe communicating failure with m_fJumpStubOverflow = TRUE to reuse existing codepaths, then eeGetRelocTypeHint on the handle value should tell me which way to go.
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For x64 there is a contract between the JIT and VM about when and how relative addressing is used: for data addresses PC-relative addressing can only be used based on getRelocTypeHint. For code addresses PC-relative addressing can always be used, and the VM will create jump stubs if necessary.
If you are using PC-relative addressing for data addresses then I expect you need to build a similar system. If you are only using it for code addresses, then I expect you need to support some form of jump stubs.
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@EgorBo Do we need a fix for arm64 version of the code @tomeksowi points at above?
Do you mean it may strip the GC related flags for frozen objects? I think we don't report them to GC anyway, do we?
Yes, that's what I meant. I was not sure if they GC refs to frozen objects need to be reported or not. If not then it seems ok.
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@EgorBo Do we need a fix for arm64 version of the code @tomeksowi points at above?
Do you mean it may strip the GC related flags for frozen objects? I think we don't report them to GC anyway, do we?
Yes, that's what I meant. I was not sure if they GC refs to frozen objects need to be reported or not. If not then it seems ok.
I think in fact we do report them today, but don't have to
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For linux-musl-riscv64
Comment threadsrc/coreclr/vm/jitinterface.cpp
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November 19, 2025 20:16
@tomeksowi@am11
fix musl build
80a6998
Co-authored-by: Adeel Mujahid <3840695+am11@users.noreply.github.com>
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lower bool
062652b
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November 25, 2025 10:42
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@tomeksowi
Merge branch 'main' into pc-rel-pointers
abacec7
Conflicts:
src/coreclr/inc/corinfo.h
src/coreclr/jit/emitriscv64.cpp
src/coreclr/tools/Common/JitInterface/CorInfoImpl.cs
src/coreclr/tools/superpmi/superpmi-shared/compileresult.cpp
src/coreclr/vm/jitinterface.cpp
@tomeksowi
Fix build
8c081a6
@tomeksowi
Fix types and format
e5ce631
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Nov 27, 2025

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VM side LGTM.
@dotnet/jit-contrib Could you please review the JIT side?
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[RISC-V] Fix too many arguments build error in emitIns_R_AI (#122555)
46de0c9
Fixes#122553, regression after #119203.
Part of #84834, cc @dotnet/samsung
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, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Universal Dark Mode - works on any site\n(function() {\n var enabled = true;\n \n function applyDarkMode() {\n if (!enabled) return;\n \n // Create style element if it doesn't exist\n var style = document.getElementById('universal-dark-mode-style');\n if (!style) {\n style = document.createElement('style');\n style.id = 'universal-dark-mode-style';\n document.head.appendChild(style);\n }\n \n // Dark mode CSS - inverts colors but preserves images/video\n style.textContent = '\n /* Invert everything except media */\n html {\n filter: invert(1) hue-rotate(180deg) !important;\n background: #1a1a2e !important;\n }\n \n /* Restore images, videos, iframes, canvas */\n img, video, iframe, canvas, svg, picture, [style*=\"background-image\"] {\n filter: invert(1) hue-rotate(180deg) !important;\n }\n \n /* Preserve specific elements that should not be inverted */\n .no-dark-mode, .no-dark-mode *,\n [data-theme=\"light\"], [data-theme=\"light\"],\n .ace_editor, .ace_editor *,\n .CodeMirror, .CodeMirror *,\n .monaco-editor, .monaco-editor *,\n .markdown-body pre, .markdown-body pre *,\n .highlight, .highlight *,\n pre code, pre code * {\n filter: none !important;\n }\n \n /* Fix common UI elements */\n .modal, .popup, .dropdown-menu, .tooltip, .popover {\n filter: invert(1) hue-rotate(180deg) !important;\n background: #2d2d44 !important;\n border-color: #444 !important;\n }\n \n /* Scrollbars */\n ::-webkit-scrollbar { background: #1a1a2e !important; }\n ::-webkit-scrollbar-thumb { background: #444 !important; }\n ::-webkit-scrollbar-thumb:hover { background: #555 !important; }\n \n /* Selection */\n ::selection { background: #4ecdc4 !important; color: #1a1a2e !important; }\n ::-moz-selection { background: #4ecdc4 !important; color: #1a1a2e !important; }\n ';\n }\n \n function removeDarkMode() {\n var style = document.getElementById('universal-dark-mode-style');\n if (style) style.remove();\n }\n \n // Toggle with Alt+Shift+D\n document.addEventListener('keydown', function(e) {\n if (e.altKey && e.shiftKey && e.key === 'D') {\n e.preventDefault();\n enabled = !enabled;\n if (enabled) {\n applyDarkMode();\n console.log('[Universal Dark Mode] Enabled');\n } else {\n removeDarkMode();\n console.log('[Universal Dark Mode] Disabled');\n }\n }\n });\n \n // Apply on load\n applyDarkMode();\n \n // Re-apply on dynamic content\n var observer = new MutationObserver(function(mutations) {\n if (enabled && !document.getElementById('universal-dark-mode-style')) {\n applyDarkMode();\n }\n });\n observer.observe(document.head, { childList: true });\n \n console.log('[Universal Dark Mode] Loaded - Press Alt+Shift+D to toggle');\n})();", "Universal Dark Mode");
}
} catch(__e) { console.warn('[Userscript:Universal Dark Mode]', __e); }
})();
})();

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[RISC-V] Synthesizing PC-relative pointer constants - #119203
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[RISC-V] Synthesizing PC-relative pointer constants#119203
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RISC-V is ill-equipped to synthesize large >32-bit constants like absolute pointers, it results in a 6-8 instruction sequence. If an address can be synthesized as PC-relative (2 instructions: auipc + ld/addi), do so. It also simplifies codegen.
Part of #84834, cc @dotnet/samsung
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RISC-V pull_request-CLR-QEMU: 9108 / 9139 (99.66%)
=======================
passed: 9108
failed: 3
skipped: 586
killed: 28
------------------------
TOTAL tests: 9725
VIRTUAL time: 80h 13min 42s 134ms
REAL time: 1h 18min 35s 828ms
=======================

report.xml, report.md, failures.xml, testclr_details.tar.zst
RISC-V pull_request-CLR-VF2: 9108 / 9139 (99.66%)
=======================
passed: 9108
failed: 3
skipped: 586
killed: 28
------------------------
TOTAL tests: 9725
VIRTUAL time: 32h 6min 37s 777ms
REAL time: 2h 7min 32s 224ms
=======================

report.xml, report.md, failures.xml, testclr_details.tar.zst
RISC-V pull_request-FX-QEMU: 0 / 0 (100.00%)
=======================
passed: 0
failed: 0
skipped: 14
killed: 0
------------------------
TOTAL tests: 14
VIRTUAL time: 0ms
REAL time: 4h 30min 0s 477ms
=======================

report.xml, report.md, failures.xml, testclr_details.tar.zst
RISC-V pull_request-FX-VF2: 0 / 61 (0.00%)
=======================
passed: 0
failed: 0
skipped: 14
killed: 61
------------------------
TOTAL tests: 75
VIRTUAL time: 1min 14s 744ms
REAL time: 13h 0min 6s 48ms
=======================

report.xml, report.md, failures.xml, testclr_details.tar.zst
Build information and commands
GIT: bd0e79cc0470c7eae53ef67028e7c567c9fb9846

CI: 0dd2da79b21e6d27378407c3af1305973fd300aa

REPO: dotnet/runtime

BRANCH: main

CONFIG: Checked

LIB_CONFIG: Release
@tomeksowi
tomeksowi
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Sep 1, 2025

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No regressions. Quite a bit of post-bringup cruft went out the window.
Diffs are based on 104,367 contexts (2,270 MinOpts, 102,097 FullOpts).
MISSED contexts: 2 (0.00%)
Overall (-9,469,872 bytes)
CollectionBase size (bytes)Diff size (bytes)PerfScore in Diffs
linux.riscv64.Checked.3.mch71,889,656-9,469,872-7.46%
MinOpts (-2,342,108 bytes)
CollectionBase size (bytes)Diff size (bytes)PerfScore in Diffs
linux.riscv64.Checked.3.mch16,685,964-2,342,108-7.73%
FullOpts (-7,127,764 bytes)
CollectionBase size (bytes)Diff size (bytes)PerfScore in Diffs
linux.riscv64.Checked.3.mch55,203,692-7,127,764-7.45%
Example diffs
linux.riscv64.Checked.3.mch
-48 (-41.38%) : 53568.dasm - Program:Main():int (FullOpts)
@@ -20,35 +20,23 @@ G_M24375_IG01: ; bbWeight=1, gcrefRegs=0000 {}, byrefRegs=0000 {}, byref,
mv fp, sp
;; size=16 bbWeight=1 PerfScore 9.00
G_M24375_IG02: ; bbWeight=1, gcrefRegs=0000 {}, byrefRegs=0000 {}, byref
- lui t6, 0xD1FFAB1E- addiw t6, t6, 0xD1FFAB1E- slli t6, t6, 13- addi t6, t6, 0xD1FFAB1E- slli t6, t6, 2- ld a0, 0xD1FFAB1E(t6)+ auipc a0, 0xD1FFAB1E+ ld a0, 0xD1FFAB1E(a0)
jalr a0 // <unknown method>
- lui t6, 0xD1FFAB1E- addiw t6, t6, 0xD1FFAB1E- slli t6, t6, 13- addi t6, t6, 0xD1FFAB1E- slli t6, t6, 2- ld a0, 0xD1FFAB1E(t6)+ auipc a0, 0xD1FFAB1E+ ld a0, 0xD1FFAB1E(a0)
jalr a0 // <unknown method>
- lui t6, 0xD1FFAB1E- addiw t6, t6, 0xD1FFAB1E- slli t6, t6, 13- addi t6, t6, 0xD1FFAB1E- slli t6, t6, 2- ld a0, 0xD1FFAB1E(t6)+ auipc a0, 0xD1FFAB1E+ ld a0, 0xD1FFAB1E(a0)
jalr a0 // Test:Ret():int
- ;; size=84 bbWeight=1 PerfScore 30.00+ ;; size=36 bbWeight=1 PerfScore 15.00
G_M24375_IG03: ; bbWeight=1, epilog, nogc, extend
ld ra, 8(sp)
ld fp, 0(sp)
addi sp, sp, 16
ret ;; size=16 bbWeight=1 PerfScore 7.50
-; Total bytes of code 116, prolog size 16, PerfScore 46.50, instruction count 17, allocated bytes for code 116 (MethodHash=d9b8a0c8) for method Program:Main():int (FullOpts)+; Total bytes of code 68, prolog size 16, PerfScore 31.50, instruction count 14, allocated bytes for code 68 (MethodHash=d9b8a0c8) for method Program:Main():int (FullOpts)
; ============================================================
Unwind Info:
@@ -59,7 +47,7 @@ Unwind Info:
E bit : 0
X bit : 0
Vers : 0
- Function Length : 58 (0x0003a) Actual length = 116 (0x000074)+ Function Length : 34 (0x00022) Actual length = 68 (0x000044)
---- Epilog scopes ----
---- Scope 0
Epilog Start Offset : 3523193630 (0xd1ffab1e) Actual offset = 3523193630 (0xd1ffab1e) Offset from main function begin = 3523193630 (0xd1ffab1e)
-32 (-40.00%) : 54962.dasm - ExceptionExtensions:RethrowWithNoStackTraceLoss(System.Exception) (FullOpts)
@@ -21,26 +21,18 @@ G_M64910_IG01: ; bbWeight=0, gcrefRegs=0000 {}, byrefRegs=0000 {}, byref,
;; size=16 bbWeight=0 PerfScore 0.00
G_M64910_IG02: ; bbWeight=0, gcrefRegs=0400 {a0}, byrefRegs=0000 {}, byref
; gcrRegs +[a0]
- lui t6, 0xD1FFAB1E- addiw t6, t6, 0xD1FFAB1E- slli t6, t6, 12- addi t6, t6, 0xD1FFAB1E- slli t6, t6, 3- ld a1, 0xD1FFAB1E(t6)+ auipc a1, 0xD1FFAB1E+ ld a1, 0xD1FFAB1E(a1)
jalr a1 // System.Runtime.ExceptionServices.ExceptionDispatchInfo:Capture(System.Exception):System.Runtime.ExceptionServices.ExceptionDispatchInfo
- lui t6, 0xD1FFAB1E- addiw t6, t6, 0xD1FFAB1E- slli t6, t6, 12- addi t6, t6, 0xD1FFAB1E- slli t6, t6, 3- ld a1, 0xD1FFAB1E(t6)+ auipc a1, 0xD1FFAB1E+ ld a1, 0xD1FFAB1E(a1)
lw zero, 0xD1FFAB1E(a0)
jalr a1 // System.Runtime.ExceptionServices.ExceptionDispatchInfo:Throw():this
; gcrRegs -[a0]
ebreak
- ;; size=64 bbWeight=0 PerfScore 0.00+ ;; size=32 bbWeight=0 PerfScore 0.00-; Total bytes of code 80, prolog size 16, PerfScore 0.00, instruction count 12, allocated bytes for code 80 (MethodHash=95e60271) for method ExceptionExtensions:RethrowWithNoStackTraceLoss(System.Exception) (FullOpts)+; Total bytes of code 48, prolog size 16, PerfScore 0.00, instruction count 10, allocated bytes for code 48 (MethodHash=95e60271) for method ExceptionExtensions:RethrowWithNoStackTraceLoss(System.Exception) (FullOpts)
; ============================================================
Unwind Info:
@@ -51,7 +43,7 @@ Unwind Info:
E bit : 0
X bit : 0
Vers : 0
- Function Length : 40 (0x00028) Actual length = 80 (0x000050)+ Function Length : 24 (0x00018) Actual length = 48 (0x000030)
---- Epilog scopes ----
No epilogs
---- Unwind codes ----
-40 (-38.46%) : 856.dasm - Interop:g__ParentDirectoryExists|7_0(System.String):bool (FullOpts)
@@ -22,25 +22,15 @@ G_M36700_IG01: ; bbWeight=1, gcrefRegs=0000 {}, byrefRegs=0000 {}, byref,
;; size=16 bbWeight=1 PerfScore 9.00
G_M36700_IG02: ; bbWeight=1, gcrefRegs=0400 {a0}, byrefRegs=0000 {}, byref
; gcrRegs +[a0]
- lui t6, 0xD1FFAB1E- addiw t6, t6, 0xD1FFAB1E- slli t6, t6, 13- addi t6, t6, 0xD1FFAB1E- slli t6, t6, 2- ld a1, 0xD1FFAB1E(t6)+ auipc a1, 0xD1FFAB1E+ ld a1, 0xD1FFAB1E(a1)
jalr a1 // System.IO.PathInternal:TrimEndingDirectorySeparator(System.String):System.String
- lui t6, 0xD1FFAB1E- addiw t6, t6, 0xD1FFAB1E- slli t6, t6, 32- srli t6, t6, 18- ld a1, 0xD1FFAB1E(t6)+ auipc a1, 0xD1FFAB1E+ ld a1, 0xD1FFAB1E(a1)
jalr a1 // System.IO.Path:GetDirectoryName(System.String):System.String
- lui t6, 0xD1FFAB1E- addiw t6, t6, 0xD1FFAB1E- slli t6, t6, 32- srli t6, t6, 18- ld a1, 0xD1FFAB1E(t6)- ;; size=72 bbWeight=1 PerfScore 25.00+ auipc a1, 0xD1FFAB1E+ ld a1, 0xD1FFAB1E(a1)+ ;; size=32 bbWeight=1 PerfScore 12.00
G_M36700_IG03: ; bbWeight=1, epilog, nogc, extend
ld ra, 8(sp)
ld fp, 0(sp)
@@ -48,7 +38,7 @@ G_M36700_IG03: ; bbWeight=1, epilog, nogc, extend
jr a1 // System.IO.Directory:Exists(System.String):bool
;; size=16 bbWeight=1 PerfScore 7.50
-; Total bytes of code 104, prolog size 16, PerfScore 41.50, instruction count 16, allocated bytes for code 104 (MethodHash=027470a3) for method Interop:<GetExceptionForIoErrno>g__ParentDirectoryExists|7_0(System.String):bool (FullOpts)+; Total bytes of code 64, prolog size 16, PerfScore 28.50, instruction count 13, allocated bytes for code 64 (MethodHash=027470a3) for method Interop:<GetExceptionForIoErrno>g__ParentDirectoryExists|7_0(System.String):bool (FullOpts)
; ============================================================
Unwind Info:
@@ -59,7 +49,7 @@ Unwind Info:
E bit : 0
X bit : 0
Vers : 0
- Function Length : 52 (0x00034) Actual length = 104 (0x000068)+ Function Length : 32 (0x00020) Actual length = 64 (0x000040)
---- Epilog scopes ----
---- Scope 0
Epilog Start Offset : 3523193630 (0xd1ffab1e) Actual offset = 3523193630 (0xd1ffab1e) Offset from main function begin = 3523193630 (0xd1ffab1e)
+0 (0.00%) : 104032.dasm - Microsoft.Diagnostics.Tracing.TraceEvent:get_FormattedMessage():System.String:this (FullOpts)
@@ -22,6 +22,7 @@ G_M51530_IG01: ; bbWeight=1, gcrefRegs=0000 {}, byrefRegs=0000 {}, byref,
G_M51530_IG02: ; bbWeight=1, gcrefRegs=0400 {a0}, byrefRegs=0000 {}, byref
; gcrRegs +[a0]
mv a1, zero
+ ; gcrRegs +[a1]
ld a2, 0xD1FFAB1E(a0)
ld a2, 0xD1FFAB1E(a2)
ld a2, 0xD1FFAB1E(a2)
+0 (0.00%) : 57024.dasm - UDivConst:U8_Div_3(ulong):ulong (FullOpts)
No diffs found?
+0 (0.00%) : 56976.dasm - SlowPathELTTests.SlowPathELTHelpers:MixedSseStructFunc():SlowPathELTTests.MixedSseStruct (FullOpts)
No diffs found?
Details
Size improvements/regressions per collection
CollectionContexts with diffsImprovementsRegressionsSame sizeImprovements (bytes)Regressions (bytes)
linux.riscv64.Checked.3.mch78,13976,85401,285-9,469,872+0
PerfScore improvements/regressions per collection
CollectionContexts with diffsImprovementsRegressionsSame PerfScoreImprovements (PerfScore)Regressions (PerfScore)PerfScore Overall in FullOpts
linux.riscv64.Checked.3.mch78,13957,537020,602-9.99%0.00%-5.6031%
Context information
CollectionDiffed contextsMinOptsFullOptsMissed, baseMissed, diff
linux.riscv64.Checked.3.mch104,3672,270102,0972 (0.00%)2 (0.00%)
jit-analyze output
@tomeksowi
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Sep 1, 2025

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+0 (0.00%) : 104032.dasm - Microsoft.Diagnostics.Tracing.TraceEvent:get_FormattedMessage():System.String:this (FullOpts)
@@ -22,6 +22,7 @@ G_M51530_IG01: ; bbWeight=1, gcrefRegs=0000 {}, byrefRegs=0000 {}, byref,
G_M51530_IG02: ; bbWeight=1, gcrefRegs=0400 {a0}, byrefRegs=0000 {}, byref
; gcrRegs +[a0]
mv a1, zero
+ ; gcrRegs +[a1]
ld a2, 0xD1FFAB1E(a0)
ld a2, 0xD1FFAB1E(a2)
ld a2, 0xD1FFAB1E(a2)
Looks like a bonus fix. Notice how this code I removed also silently stripped GC flags.
runtime/src/coreclr/jit/codegenriscv64.cpp

Lines 902 to 905
in
f1cbe0f
if (!compiler->opts.compReloc) 
 { 
 size = EA_SIZE(size); // Strip any Reloc flags from size if we aren't doing relocs.
 } 
@tomeksowi
tomeksowi
marked this pull request as ready for review
September 2, 2025 06:23
@JulieLeeMSFT
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Oct 6, 2025

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We will review .NET 11 PRs when we are done with .NET 10 last minute works and less busy. Please give us a few more weeks.

CC @jakobbotsch.
@steveisoksteveisok
added this to the 11.0.0 milestone
Oct 6, 2025
@jakobbotsch
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Oct 21, 2025

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@EgorBo Do we need a fix for arm64 version of the code @tomeksowi points at above?
runtime/src/coreclr/jit/codegenarm64.cpp

Lines 2098 to 2101
in
25e088f
if (!compiler->opts.compReloc) 
 { 
 size = EA_SIZE(size); // Strip any Reloc flags from size if we aren't doing relocs
 } 
For address 0 it is clearly not a problem -- would it be a problem for frozen objects?
@jakobbotsch
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Oct 21, 2025

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If an address can be synthesized as PC-relative (2 instructions: auipc + ld/addi), do so.
Note that it's generally impossible to know where the code will be located, so you can only do this heuristically. How do you recover when you get it wrong?
For x64 we recover the situation by disabling rip-relative addressing globally the first time it happens, and then designing things so that it very rarely happens. Look for m_fAllowRel32.
@EgorBo
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Oct 21, 2025

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@EgorBo Do we need a fix for arm64 version of the code @tomeksowi points at above?
Do you mean it may strip the GC related flags for frozen objects? I think we don't report them to GC anyway, do we?
@tomeksowi
tomeksowi
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Oct 22, 2025

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Note that it's generally impossible to know where the code will be located, so you can only do this heuristically. How do you recover when you get it wrong?
For x64 we recover the situation by disabling rip-relative addressing globally the first time it happens, and then designing things so that it very rarely happens. Look for m_fAllowRel32.
I don't recover, the address of a handle with function address was always within range, but you're right, IsIconHandle(GTF_ICON_FTN_ADDR) is just a heuristic. I remember looking at m_fAllowRel32 briefly but abandoned it because it seemed linked to jump stubs which RISC-V doesn't use (and aren't applicable here since we're doing loads for the handles).
I'll try to use it, maybe communicating failure with m_fJumpStubOverflow = TRUE to reuse existing codepaths, then eeGetRelocTypeHint on the handle value should tell me which way to go.
@jakobbotsch
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Oct 22, 2025

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For x64 there is a contract between the JIT and VM about when and how relative addressing is used: for data addresses PC-relative addressing can only be used based on getRelocTypeHint. For code addresses PC-relative addressing can always be used, and the VM will create jump stubs if necessary.
If you are using PC-relative addressing for data addresses then I expect you need to build a similar system. If you are only using it for code addresses, then I expect you need to support some form of jump stubs.
@jakobbotsch
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Oct 22, 2025

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@EgorBo Do we need a fix for arm64 version of the code @tomeksowi points at above?
Do you mean it may strip the GC related flags for frozen objects? I think we don't report them to GC anyway, do we?
Yes, that's what I meant. I was not sure if they GC refs to frozen objects need to be reported or not. If not then it seems ok.
@EgorBo
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Oct 22, 2025

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@EgorBo Do we need a fix for arm64 version of the code @tomeksowi points at above?
Do you mean it may strip the GC related flags for frozen objects? I think we don't report them to GC anyway, do we?
Yes, that's what I meant. I was not sure if they GC refs to frozen objects need to be reported or not. If not then it seems ok.
I think in fact we do report them today, but don't have to
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For linux-musl-riscv64
Comment threadsrc/coreclr/vm/jitinterface.cpp
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Comment threadsrc/coreclr/vm/jitinterface.cpp
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jkotas
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Comment threadsrc/coreclr/tools/superpmi/superpmi-shared/compileresult.cpp
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tomeksowiand others
added 2 commits
November 19, 2025 20:16
@tomeksowi@am11
fix musl build
80a6998
Co-authored-by: Adeel Mujahid <3840695+am11@users.noreply.github.com>
@tomeksowi
lower bool
062652b
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Comment threadsrc/coreclr/tools/Common/Compiler/ObjectWriter/ElfObjectWriter.cs
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@tomeksowi
tomeksowi
marked this pull request as ready for review
November 25, 2025 10:42
@jakobbotschjakobbotsch
mentioned this pull request
Nov 25, 2025
 Merged

@tomeksowi
Merge branch 'main' into pc-rel-pointers
abacec7
Conflicts:
src/coreclr/inc/corinfo.h
src/coreclr/jit/emitriscv64.cpp
src/coreclr/tools/Common/JitInterface/CorInfoImpl.cs
src/coreclr/tools/superpmi/superpmi-shared/compileresult.cpp
src/coreclr/vm/jitinterface.cpp
@tomeksowi
Fix build
8c081a6
@tomeksowi
Fix types and format
e5ce631
@jkotas
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Nov 27, 2025

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VM side LGTM.
@dotnet/jit-contrib Could you please review the JIT side?
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@jakobbotsch
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merged commit f50a572
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@tomeksowi
[RISC-V] Fix too many arguments build error in emitIns_R_AI (#122555)
46de0c9
Fixes#122553, regression after #119203.
Part of #84834, cc @dotnet/samsung
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@jakobbotschjakobbotschjakobbotsch approved these changes
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@tomeksowi@risc-vv@JulieLeeMSFT@jakobbotsch@EgorBo@jkotas@kg@am11@steveisok@clamp03