JIT: Move loop inversion to after loop recognition#115850

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amanasifkhalid merged 6 commits into from
Jun 14, 2025
Merged

JIT: Move loop inversion to after loop recognition #115850

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a8f13aa
Move loop inversion to after loop recognition
amanasifkhalid May 21, 2025
5107d7e
Merge branch 'main' into move-loop-inversion
amanasifkhalid May 22, 2025
2d94818
Merge from main
amanasifkhalid Jun 4, 2025
c951e44
Merge branch 'main' into move-loop-inversion
amanasifkhalid Jun 13, 2025
d669fad
Fix profile consistency
amanasifkhalid Jun 13, 2025
81ce3f6
Remove fgRenumberBlocks
amanasifkhalid Jun 13, 2025
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8 changes: 4 additions & 4 deletions src/coreclr/jit/compiler.cpp
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Original file line numberDiff line numberDiff line change
Expand Up@@ -4576,10 +4576,6 @@ void Compiler::compCompile(void** methodCodePtr, uint32_t* methodCodeSize, JitFl
//
DoPhase(this, PHASE_EMPTY_TRY_CATCH_FAULT_2, &Compiler::fgRemoveEmptyTryCatchOrTryFault);

// Invert loops
//
DoPhase(this, PHASE_INVERT_LOOPS, &Compiler::optInvertLoops);

// Run some flow graph optimizations (but don't reorder)
//
DoPhase(this, PHASE_OPTIMIZE_FLOW, &Compiler::optOptimizeFlow);
Expand All@@ -4602,6 +4598,10 @@ void Compiler::compCompile(void** methodCodePtr, uint32_t* methodCodeSize, JitFl
//
DoPhase(this, PHASE_REPAIR_PROFILE_POST_MORPH, &Compiler::fgRepairProfile);

// Invert loops
//
DoPhase(this, PHASE_INVERT_LOOPS, &Compiler::optInvertLoops);

// Scale block weights and mark run rarely blocks.
//
DoPhase(this, PHASE_SET_BLOCK_WEIGHTS, &Compiler::optSetBlockWeights);
Expand Down
2 changes: 0 additions & 2 deletions src/coreclr/jit/compiler.h
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Original file line numberDiff line numberDiff line change
Expand Up@@ -6164,8 +6164,6 @@ class Compiler

void fgCompactBlock(BasicBlock* block);

bool fgRenumberBlocks();

bool fgExpandRarelyRunBlocks();

bool fgEhAllowsMoveBlock(BasicBlock* bBefore, BasicBlock* bAfter);
Expand Down
67 changes: 0 additions & 67 deletions src/coreclr/jit/fgbasic.cpp
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Original file line numberDiff line numberDiff line change
Expand Up@@ -5285,73 +5285,6 @@ void Compiler::fgPrepareCallFinallyRetForRemoval(BasicBlock* block)
block->SetKind(BBJ_ALWAYS);
}

//------------------------------------------------------------------------
// fgRenumberBlocks: update block bbNums to reflect bbNext order
//
// Returns:
// true if blocks were renumbered or maxBBNum was updated.
//
// Notes:
// Walk the flow graph, reassign block numbers to keep them in ascending order.
// Return 'true' if any renumbering was actually done, OR if we change the
// maximum number of assigned basic blocks (this can happen if we do inlining,
// create a new, high-numbered block, then that block goes away. We go to
// renumber the blocks, none of them actually change number, but we shrink the
// maximum assigned block number. This affects the block set epoch).
//
bool Compiler::fgRenumberBlocks()
{
assert(fgPredsComputed);

JITDUMP("\n*************** Before renumbering the basic blocks\n");
JITDUMPEXEC(fgDispBasicBlocks());
JITDUMPEXEC(fgDispHandlerTab());

bool renumbered = false;
bool newMaxBBNum = false;
unsigned num = 1;

for (BasicBlock* block : Blocks())
{
noway_assert(!block->HasFlag(BBF_REMOVED));

if (block->bbNum != num)
{
JITDUMP("Renumber " FMT_BB " to " FMT_BB "\n", block->bbNum, num);
renumbered = true;
block->bbNum = num;
}

if (block->IsLast())
{
fgLastBB = block;
if (fgBBNumMax != num)
{
fgBBNumMax = num;
newMaxBBNum = true;
}
}

num++;
}

// If we renumbered, then we may need to reorder some pred lists.
//
if (renumbered)
{
JITDUMP("\n*************** After renumbering the basic blocks\n");
JITDUMPEXEC(fgDispBasicBlocks());
JITDUMPEXEC(fgDispHandlerTab());
}
else
{
JITDUMP("=============== No blocks renumbered!\n");
}

// Tell our caller if any blocks actually were renumbered.
return renumbered || newMaxBBNum;
}

/*****************************************************************************
*
* Is the BasicBlock bJump a forward branch?
Expand Down
6 changes: 3 additions & 3 deletions src/coreclr/jit/fgdiagnostic.cpp
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Open in desktop
Original file line numberDiff line numberDiff line change
Expand Up@@ -2873,9 +2873,9 @@ bool BBPredsChecker::CheckEHFinallyRet(BasicBlock* blockPred, BasicBlock* block)
//------------------------------------------------------------------------------
// fgDebugCheckBBNumIncreasing: Check that the block list bbNum are in increasing order in the bbNext
// traversal. Given a block B1 and its bbNext successor B2, this means `B1->bbNum < B2->bbNum`, but not
// that `B1->bbNum + 1 == B2->bbNum` (which is true after renumbering). This can be used as a precondition
// to a phase that expects this ordering to compare block numbers (say, to look for backwards branches)
// and doesn't want to call fgRenumberBlocks(), to avoid that potential expense.
// that `B1->bbNum + 1 == B2->bbNum`.
// This can be used as a precondition to a phase that expects this ordering to compare block numbers
// (say, to look for backwards branches).
//
void Compiler::fgDebugCheckBBNumIncreasing()
{
Expand Down
44 changes: 29 additions & 15 deletions src/coreclr/jit/optimizer.cpp
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Original file line numberDiff line numberDiff line change
Expand Up@@ -2123,16 +2123,12 @@ bool Compiler::optTryInvertWhileLoop(FlowGraphNaturalLoop* loop)
newPreheader->setBBProfileWeight(newCondToNewPreheader->getLikelyWeight());
exit->decreaseBBProfileWeight(newCondToNewExit->getLikelyWeight());

// Update the weight for the duplicated blocks. Normally, this reduces
// the weight of condBlock, except in odd cases of stress modes with
// inconsistent weights.
// Update the duplicated blocks' weights

for (int i = 0; i < (duplicatedBlocks.Height() - 1); i++)
{
BasicBlock* block = duplicatedBlocks.Bottom(i);
JITDUMP("Reducing profile weight of " FMT_BB " from " FMT_WT " to " FMT_WT "\n", block->bbNum, weightCond,
weightStayInLoopSucc);
block->setBBProfileWeight(weightStayInLoopSucc);
block->setBBProfileWeight(block->computeIncomingWeight());
}

condBlock->setBBProfileWeight(condBlock->computeIncomingWeight());
Expand DownExpand Up@@ -2188,20 +2184,38 @@ PhaseStatus Compiler::optInvertLoops()
}
#endif // OPT_CONFIG

if (compCodeOpt() != SMALL_CODE)
if (compCodeOpt() == SMALL_CODE)
{
fgDfsBlocksAndRemove();
optFindLoops();
for (FlowGraphNaturalLoop* loop : m_loops->InPostOrder())
{
optTryInvertWhileLoop(loop);
}
return PhaseStatus::MODIFIED_NOTHING;
}

bool madeChanges = false;
for (FlowGraphNaturalLoop* loop : m_loops->InPostOrder())
{
madeChanges |= optTryInvertWhileLoop(loop);
}

if (Metrics.LoopsInverted > 0)
Comment thread
amanasifkhalid marked this conversation as resolved.
{
assert(madeChanges);
fgInvalidateDfsTree();
return PhaseStatus::MODIFIED_EVERYTHING;
m_dfsTree = fgComputeDfs();
m_loops = FlowGraphNaturalLoops::Find(m_dfsTree);

// In normal cases no further canonicalization will be required as we
// try to ensure loops stay canonicalized during inversion. However,
// duplicating the condition outside an inner loop can introduce new
// exits in the parent loop, so we may rarely need to recanonicalize
// exit blocks.
if (optCanonicalizeLoops())
{
fgInvalidateDfsTree();
m_dfsTree = fgComputeDfs();
m_loops = FlowGraphNaturalLoops::Find(m_dfsTree);
}
}

return PhaseStatus::MODIFIED_NOTHING;
return madeChanges ? PhaseStatus::MODIFIED_EVERYTHING : PhaseStatus::MODIFIED_NOTHING;
}

//-----------------------------------------------------------------------------
Expand Down
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(function() {
function addCopyButtons() {
document.querySelectorAll('pre code').forEach(function(codeBlock) {
if (codeBlock.parentElement.hasAttribute('data-copy-added')) return;
codeBlock.parentElement.setAttribute('data-copy-added', 'true');
var btn = document.createElement('button');
btn.textContent = 'Copy';
btn.style.cssText = 'position:absolute;top:4px;right:4px;padding:2px 8px;font-size:11px;background:#4ecdc4;border:none;border-radius:4px;color:#1a1a2e;cursor:pointer;opacity:0.7;transition:opacity 0.2s;';
btn.onmouseover = function() { this.style.opacity = '1'; };
btn.onmouseout = function() { this.style.opacity = '0.7'; };
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navigator.clipboard.writeText(codeBlock.textContent).then(function() {
btn.textContent = 'Copied!';
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});
};
codeBlock.parentElement.style.position = 'relative';
codeBlock.parentElement.appendChild(btn);
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}
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var observer = new MutationObserver(addCopyButtons);
observer.observe(document.body, { childList: true, subtree: true });
})();
}
} catch(__e) { console.warn('[Userscript:Add Copy Buttons to Code Blocks]', __e); }
})();
(function(){
try {
var __m = "github.com";
var __re = new RegExp('^' + "github\\.com" + '

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JIT: Move loop inversion to after loop recognition#115850

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 Merged

amanasifkhalid
merged 6 commits into

from

Jun 14, 2025
 Merged


JIT: Move loop inversion to after loop recognition
#115850
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a8f13aa

Move loop inversion to after loop recognition


amanasifkhalid May 21, 2025
5107d7e

Merge branch 'main' into move-loop-inversion


amanasifkhalid May 22, 2025
2d94818

Merge from main


amanasifkhalid Jun 4, 2025
c951e44

Merge branch 'main' into move-loop-inversion


amanasifkhalid Jun 13, 2025
d669fad

Fix profile consistency


amanasifkhalid Jun 13, 2025
81ce3f6

Remove fgRenumberBlocks


amanasifkhalid Jun 13, 2025

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8 changes: 4 additions & 4 deletions
src/coreclr/jit/compiler.cpp

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Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -4576,10 +4576,6 @@ void Compiler::compCompile(void** methodCodePtr, uint32_t* methodCodeSize, JitFl
 //
 DoPhase(this, PHASE_EMPTY_TRY_CATCH_FAULT_2, &Compiler::fgRemoveEmptyTryCatchOrTryFault);

 // Invert loops
 //
 DoPhase(this, PHASE_INVERT_LOOPS, &Compiler::optInvertLoops);

 // Run some flow graph optimizations (but don't reorder)
 //
 DoPhase(this, PHASE_OPTIMIZE_FLOW, &Compiler::optOptimizeFlow);
Expand All@@ -4602,6 +4598,10 @@ void Compiler::compCompile(void** methodCodePtr, uint32_t* methodCodeSize, JitFl
 //
 DoPhase(this, PHASE_REPAIR_PROFILE_POST_MORPH, &Compiler::fgRepairProfile);

 // Invert loops
 //
 DoPhase(this, PHASE_INVERT_LOOPS, &Compiler::optInvertLoops);

 // Scale block weights and mark run rarely blocks.
 //
 DoPhase(this, PHASE_SET_BLOCK_WEIGHTS, &Compiler::optSetBlockWeights);
Expand Down

2 changes: 0 additions & 2 deletions
src/coreclr/jit/compiler.h

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Original file line numberDiff line numberDiff line change
Expand Up@@ -6164,8 +6164,6 @@ class Compiler

 void fgCompactBlock(BasicBlock* block);

 bool fgRenumberBlocks();

 bool fgExpandRarelyRunBlocks();

 bool fgEhAllowsMoveBlock(BasicBlock* bBefore, BasicBlock* bAfter);
Expand Down

67 changes: 0 additions & 67 deletions
src/coreclr/jit/fgbasic.cpp

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Original file line numberDiff line numberDiff line change
Expand Up@@ -5285,73 +5285,6 @@ void Compiler::fgPrepareCallFinallyRetForRemoval(BasicBlock* block)
 block->SetKind(BBJ_ALWAYS);
}

//------------------------------------------------------------------------
// fgRenumberBlocks: update block bbNums to reflect bbNext order
//
// Returns:
// true if blocks were renumbered or maxBBNum was updated.
//
// Notes:
// Walk the flow graph, reassign block numbers to keep them in ascending order.
// Return 'true' if any renumbering was actually done, OR if we change the
// maximum number of assigned basic blocks (this can happen if we do inlining,
// create a new, high-numbered block, then that block goes away. We go to
// renumber the blocks, none of them actually change number, but we shrink the
// maximum assigned block number. This affects the block set epoch).
//
bool Compiler::fgRenumberBlocks()
{
 assert(fgPredsComputed);

 JITDUMP("\n*************** Before renumbering the basic blocks\n");
 JITDUMPEXEC(fgDispBasicBlocks());
 JITDUMPEXEC(fgDispHandlerTab());

 bool renumbered = false;
 bool newMaxBBNum = false;
 unsigned num = 1;

 for (BasicBlock* block : Blocks())
 {
 noway_assert(!block->HasFlag(BBF_REMOVED));

 if (block->bbNum != num)
 {
 JITDUMP("Renumber " FMT_BB " to " FMT_BB "\n", block->bbNum, num);
 renumbered = true;
 block->bbNum = num;
 }

 if (block->IsLast())
 {
 fgLastBB = block;
 if (fgBBNumMax != num)
 {
 fgBBNumMax = num;
 newMaxBBNum = true;
 }
 }

 num++;
 }

 // If we renumbered, then we may need to reorder some pred lists.
 //
 if (renumbered)
 {
 JITDUMP("\n*************** After renumbering the basic blocks\n");
 JITDUMPEXEC(fgDispBasicBlocks());
 JITDUMPEXEC(fgDispHandlerTab());
 }
 else
 {
 JITDUMP("=============== No blocks renumbered!\n");
 }

 // Tell our caller if any blocks actually were renumbered.
 return renumbered || newMaxBBNum;
}

/*****************************************************************************
 *
 * Is the BasicBlock bJump a forward branch?
Expand Down

6 changes: 3 additions & 3 deletions
src/coreclr/jit/fgdiagnostic.cpp

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Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -2873,9 +2873,9 @@ bool BBPredsChecker::CheckEHFinallyRet(BasicBlock* blockPred, BasicBlock* block)
//------------------------------------------------------------------------------
// fgDebugCheckBBNumIncreasing: Check that the block list bbNum are in increasing order in the bbNext
// traversal. Given a block B1 and its bbNext successor B2, this means `B1->bbNum < B2->bbNum`, but not
// that `B1->bbNum + 1 == B2->bbNum` (which is true after renumbering). This can be used as a precondition
// to a phase that expects this ordering to compare block numbers (say, to look for backwards branches)
// and doesn't want to call fgRenumberBlocks(), to avoid that potential expense.
// that `B1->bbNum + 1 == B2->bbNum`.
// This can be used as a precondition to a phase that expects this ordering to compare block numbers
// (say, to look for backwards branches).
//
void Compiler::fgDebugCheckBBNumIncreasing()
{
Expand Down

44 changes: 29 additions & 15 deletions
src/coreclr/jit/optimizer.cpp

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Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -2123,16 +2123,12 @@ bool Compiler::optTryInvertWhileLoop(FlowGraphNaturalLoop* loop)
 newPreheader->setBBProfileWeight(newCondToNewPreheader->getLikelyWeight());
 exit->decreaseBBProfileWeight(newCondToNewExit->getLikelyWeight());

 // Update the weight for the duplicated blocks. Normally, this reduces
 // the weight of condBlock, except in odd cases of stress modes with
 // inconsistent weights.
 // Update the duplicated blocks' weights

 for (int i = 0; i < (duplicatedBlocks.Height() - 1); i++)
 {
 BasicBlock* block = duplicatedBlocks.Bottom(i);
 JITDUMP("Reducing profile weight of " FMT_BB " from " FMT_WT " to " FMT_WT "\n", block->bbNum, weightCond,
 weightStayInLoopSucc);
 block->setBBProfileWeight(weightStayInLoopSucc);
 block->setBBProfileWeight(block->computeIncomingWeight());
 }

 condBlock->setBBProfileWeight(condBlock->computeIncomingWeight());
Expand DownExpand Up@@ -2188,20 +2184,38 @@ PhaseStatus Compiler::optInvertLoops()
 }
#endif // OPT_CONFIG

 if (compCodeOpt() != SMALL_CODE)
 if (compCodeOpt() == SMALL_CODE)
 {
 fgDfsBlocksAndRemove();
 optFindLoops();
 for (FlowGraphNaturalLoop* loop : m_loops->InPostOrder())
 {
 optTryInvertWhileLoop(loop);
 }
 return PhaseStatus::MODIFIED_NOTHING;
 }

 bool madeChanges = false;
 for (FlowGraphNaturalLoop* loop : m_loops->InPostOrder())
 {
 madeChanges |= optTryInvertWhileLoop(loop);
 }

 if (Metrics.LoopsInverted > 0)
Comment thread
amanasifkhalid marked this conversation as resolved.

 {
 assert(madeChanges);
 fgInvalidateDfsTree();
 return PhaseStatus::MODIFIED_EVERYTHING;
 m_dfsTree = fgComputeDfs();
 m_loops = FlowGraphNaturalLoops::Find(m_dfsTree);

 // In normal cases no further canonicalization will be required as we
 // try to ensure loops stay canonicalized during inversion. However,
 // duplicating the condition outside an inner loop can introduce new
 // exits in the parent loop, so we may rarely need to recanonicalize
 // exit blocks.
 if (optCanonicalizeLoops())
 {
 fgInvalidateDfsTree();
 m_dfsTree = fgComputeDfs();
 m_loops = FlowGraphNaturalLoops::Find(m_dfsTree);
 }
 }

 return PhaseStatus::MODIFIED_NOTHING;
 return madeChanges ? PhaseStatus::MODIFIED_EVERYTHING : PhaseStatus::MODIFIED_NOTHING;
}

//-----------------------------------------------------------------------------
Expand Down

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var style = document.createElement('style');
style.textContent = '
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var __m = "*";
var __re = new RegExp('^' + ".*" + '

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JIT: Move loop inversion to after loop recognition#115850

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 Merged

amanasifkhalid
merged 6 commits into

from

Jun 14, 2025
 Merged


JIT: Move loop inversion to after loop recognition
#115850
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a8f13aa

Move loop inversion to after loop recognition


amanasifkhalid May 21, 2025
5107d7e

Merge branch 'main' into move-loop-inversion


amanasifkhalid May 22, 2025
2d94818

Merge from main


amanasifkhalid Jun 4, 2025
c951e44

Merge branch 'main' into move-loop-inversion


amanasifkhalid Jun 13, 2025
d669fad

Fix profile consistency


amanasifkhalid Jun 13, 2025
81ce3f6

Remove fgRenumberBlocks


amanasifkhalid Jun 13, 2025

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8 changes: 4 additions & 4 deletions
src/coreclr/jit/compiler.cpp

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -4576,10 +4576,6 @@ void Compiler::compCompile(void** methodCodePtr, uint32_t* methodCodeSize, JitFl
 //
 DoPhase(this, PHASE_EMPTY_TRY_CATCH_FAULT_2, &Compiler::fgRemoveEmptyTryCatchOrTryFault);

 // Invert loops
 //
 DoPhase(this, PHASE_INVERT_LOOPS, &Compiler::optInvertLoops);

 // Run some flow graph optimizations (but don't reorder)
 //
 DoPhase(this, PHASE_OPTIMIZE_FLOW, &Compiler::optOptimizeFlow);
Expand All@@ -4602,6 +4598,10 @@ void Compiler::compCompile(void** methodCodePtr, uint32_t* methodCodeSize, JitFl
 //
 DoPhase(this, PHASE_REPAIR_PROFILE_POST_MORPH, &Compiler::fgRepairProfile);

 // Invert loops
 //
 DoPhase(this, PHASE_INVERT_LOOPS, &Compiler::optInvertLoops);

 // Scale block weights and mark run rarely blocks.
 //
 DoPhase(this, PHASE_SET_BLOCK_WEIGHTS, &Compiler::optSetBlockWeights);
Expand Down

2 changes: 0 additions & 2 deletions
src/coreclr/jit/compiler.h

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Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -6164,8 +6164,6 @@ class Compiler

 void fgCompactBlock(BasicBlock* block);

 bool fgRenumberBlocks();

 bool fgExpandRarelyRunBlocks();

 bool fgEhAllowsMoveBlock(BasicBlock* bBefore, BasicBlock* bAfter);
Expand Down

67 changes: 0 additions & 67 deletions
src/coreclr/jit/fgbasic.cpp

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Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -5285,73 +5285,6 @@ void Compiler::fgPrepareCallFinallyRetForRemoval(BasicBlock* block)
 block->SetKind(BBJ_ALWAYS);
}

//------------------------------------------------------------------------
// fgRenumberBlocks: update block bbNums to reflect bbNext order
//
// Returns:
// true if blocks were renumbered or maxBBNum was updated.
//
// Notes:
// Walk the flow graph, reassign block numbers to keep them in ascending order.
// Return 'true' if any renumbering was actually done, OR if we change the
// maximum number of assigned basic blocks (this can happen if we do inlining,
// create a new, high-numbered block, then that block goes away. We go to
// renumber the blocks, none of them actually change number, but we shrink the
// maximum assigned block number. This affects the block set epoch).
//
bool Compiler::fgRenumberBlocks()
{
 assert(fgPredsComputed);

 JITDUMP("\n*************** Before renumbering the basic blocks\n");
 JITDUMPEXEC(fgDispBasicBlocks());
 JITDUMPEXEC(fgDispHandlerTab());

 bool renumbered = false;
 bool newMaxBBNum = false;
 unsigned num = 1;

 for (BasicBlock* block : Blocks())
 {
 noway_assert(!block->HasFlag(BBF_REMOVED));

 if (block->bbNum != num)
 {
 JITDUMP("Renumber " FMT_BB " to " FMT_BB "\n", block->bbNum, num);
 renumbered = true;
 block->bbNum = num;
 }

 if (block->IsLast())
 {
 fgLastBB = block;
 if (fgBBNumMax != num)
 {
 fgBBNumMax = num;
 newMaxBBNum = true;
 }
 }

 num++;
 }

 // If we renumbered, then we may need to reorder some pred lists.
 //
 if (renumbered)
 {
 JITDUMP("\n*************** After renumbering the basic blocks\n");
 JITDUMPEXEC(fgDispBasicBlocks());
 JITDUMPEXEC(fgDispHandlerTab());
 }
 else
 {
 JITDUMP("=============== No blocks renumbered!\n");
 }

 // Tell our caller if any blocks actually were renumbered.
 return renumbered || newMaxBBNum;
}

/*****************************************************************************
 *
 * Is the BasicBlock bJump a forward branch?
Expand Down

6 changes: 3 additions & 3 deletions
src/coreclr/jit/fgdiagnostic.cpp

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Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -2873,9 +2873,9 @@ bool BBPredsChecker::CheckEHFinallyRet(BasicBlock* blockPred, BasicBlock* block)
//------------------------------------------------------------------------------
// fgDebugCheckBBNumIncreasing: Check that the block list bbNum are in increasing order in the bbNext
// traversal. Given a block B1 and its bbNext successor B2, this means `B1->bbNum < B2->bbNum`, but not
// that `B1->bbNum + 1 == B2->bbNum` (which is true after renumbering). This can be used as a precondition
// to a phase that expects this ordering to compare block numbers (say, to look for backwards branches)
// and doesn't want to call fgRenumberBlocks(), to avoid that potential expense.
// that `B1->bbNum + 1 == B2->bbNum`.
// This can be used as a precondition to a phase that expects this ordering to compare block numbers
// (say, to look for backwards branches).
//
void Compiler::fgDebugCheckBBNumIncreasing()
{
Expand Down

44 changes: 29 additions & 15 deletions
src/coreclr/jit/optimizer.cpp

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Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -2123,16 +2123,12 @@ bool Compiler::optTryInvertWhileLoop(FlowGraphNaturalLoop* loop)
 newPreheader->setBBProfileWeight(newCondToNewPreheader->getLikelyWeight());
 exit->decreaseBBProfileWeight(newCondToNewExit->getLikelyWeight());

 // Update the weight for the duplicated blocks. Normally, this reduces
 // the weight of condBlock, except in odd cases of stress modes with
 // inconsistent weights.
 // Update the duplicated blocks' weights

 for (int i = 0; i < (duplicatedBlocks.Height() - 1); i++)
 {
 BasicBlock* block = duplicatedBlocks.Bottom(i);
 JITDUMP("Reducing profile weight of " FMT_BB " from " FMT_WT " to " FMT_WT "\n", block->bbNum, weightCond,
 weightStayInLoopSucc);
 block->setBBProfileWeight(weightStayInLoopSucc);
 block->setBBProfileWeight(block->computeIncomingWeight());
 }

 condBlock->setBBProfileWeight(condBlock->computeIncomingWeight());
Expand DownExpand Up@@ -2188,20 +2184,38 @@ PhaseStatus Compiler::optInvertLoops()
 }
#endif // OPT_CONFIG

 if (compCodeOpt() != SMALL_CODE)
 if (compCodeOpt() == SMALL_CODE)
 {
 fgDfsBlocksAndRemove();
 optFindLoops();
 for (FlowGraphNaturalLoop* loop : m_loops->InPostOrder())
 {
 optTryInvertWhileLoop(loop);
 }
 return PhaseStatus::MODIFIED_NOTHING;
 }

 bool madeChanges = false;
 for (FlowGraphNaturalLoop* loop : m_loops->InPostOrder())
 {
 madeChanges |= optTryInvertWhileLoop(loop);
 }

 if (Metrics.LoopsInverted > 0)
Comment thread
amanasifkhalid marked this conversation as resolved.

 {
 assert(madeChanges);
 fgInvalidateDfsTree();
 return PhaseStatus::MODIFIED_EVERYTHING;
 m_dfsTree = fgComputeDfs();
 m_loops = FlowGraphNaturalLoops::Find(m_dfsTree);

 // In normal cases no further canonicalization will be required as we
 // try to ensure loops stay canonicalized during inversion. However,
 // duplicating the condition outside an inner loop can introduce new
 // exits in the parent loop, so we may rarely need to recanonicalize
 // exit blocks.
 if (optCanonicalizeLoops())
 {
 fgInvalidateDfsTree();
 m_dfsTree = fgComputeDfs();
 m_loops = FlowGraphNaturalLoops::Find(m_dfsTree);
 }
 }

 return PhaseStatus::MODIFIED_NOTHING;
 return madeChanges ? PhaseStatus::MODIFIED_EVERYTHING : PhaseStatus::MODIFIED_NOTHING;
}

//-----------------------------------------------------------------------------
Expand Down

, 'i');
if (__m === '*' || __re.test(location.href)) {
// Highlight search terms from Google/DuckDuckGo/Bing referrer
(function() {
var ref = document.referrer;
var terms = [];
if (ref.includes('google.com') || ref.includes('duckduckgo.com') || ref.includes('bing.com')) {
var url = new URL(ref);
var q = url.searchParams.get('q') || url.searchParams.get('p');
if (q) {
terms = q.split(/\s+/).filter(function(t) { return t.length > 2; });
}
}
if (terms.length === 0) return;
var style = document.createElement('style');
style.textContent = '.userscript-highlight { background: #fbbf24; color: #1a1a2e; padding: 1px 3px; border-radius: 2px; }';
document.head.appendChild(style);
function highlight(node) {
if (node.nodeType === 3) { // text node
var text = node.textContent;
var found = false;
terms.forEach(function(term) {
var regex = new RegExp('(' + term.replace(/[.*+?^${}()|[\]\\]/g, '\\') + ')', 'gi');
if (regex.test(text)) {
found = true;
var frag = document.createDocumentFragment();
var parts = text.split(regex);
parts.forEach(function(part, i) {
if (i % 2 === 0) {
frag.appendChild(document.createTextNode(part));
} else {
var span = document.createElement('span');
span.className = 'userscript-highlight';
span.textContent = part;
frag.appendChild(span);
}
});
node.parentNode.replaceChild(frag, node);
}
});
} else if (node.nodeType === 1 && node.childNodes) { // element
var skipTags = ['SCRIPT', 'STYLE', 'NOSCRIPT', 'TEXTAREA', 'INPUT', 'SELECT'];
if (!skipTags.includes(node.tagName)) {
Array.from(node.childNodes).forEach(highlight);
}
}
}
highlight(document.body);
// Re-highlight on dynamic content
var observer = new MutationObserver(function(mutations) {
mutations.forEach(function(m) {
m.addedNodes.forEach(function(node) {
if (node.nodeType === 1 || node.nodeType === 3) highlight(node);
});
});
});
observer.observe(document.body, { childList: true, subtree: true });
})();
}
} catch(__e) { console.warn('[Userscript:Highlight Search Terms]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

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JIT: Move loop inversion to after loop recognition#115850

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JIT: Move loop inversion to after loop recognition
#115850
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a8f13aa

Move loop inversion to after loop recognition


amanasifkhalid May 21, 2025
5107d7e

Merge branch 'main' into move-loop-inversion


amanasifkhalid May 22, 2025
2d94818

Merge from main


amanasifkhalid Jun 4, 2025
c951e44

Merge branch 'main' into move-loop-inversion


amanasifkhalid Jun 13, 2025
d669fad

Fix profile consistency


amanasifkhalid Jun 13, 2025
81ce3f6

Remove fgRenumberBlocks


amanasifkhalid Jun 13, 2025

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8 changes: 4 additions & 4 deletions
src/coreclr/jit/compiler.cpp

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -4576,10 +4576,6 @@ void Compiler::compCompile(void** methodCodePtr, uint32_t* methodCodeSize, JitFl
 //
 DoPhase(this, PHASE_EMPTY_TRY_CATCH_FAULT_2, &Compiler::fgRemoveEmptyTryCatchOrTryFault);

 // Invert loops
 //
 DoPhase(this, PHASE_INVERT_LOOPS, &Compiler::optInvertLoops);

 // Run some flow graph optimizations (but don't reorder)
 //
 DoPhase(this, PHASE_OPTIMIZE_FLOW, &Compiler::optOptimizeFlow);
Expand All@@ -4602,6 +4598,10 @@ void Compiler::compCompile(void** methodCodePtr, uint32_t* methodCodeSize, JitFl
 //
 DoPhase(this, PHASE_REPAIR_PROFILE_POST_MORPH, &Compiler::fgRepairProfile);

 // Invert loops
 //
 DoPhase(this, PHASE_INVERT_LOOPS, &Compiler::optInvertLoops);

 // Scale block weights and mark run rarely blocks.
 //
 DoPhase(this, PHASE_SET_BLOCK_WEIGHTS, &Compiler::optSetBlockWeights);
Expand Down

2 changes: 0 additions & 2 deletions
src/coreclr/jit/compiler.h

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Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -6164,8 +6164,6 @@ class Compiler

 void fgCompactBlock(BasicBlock* block);

 bool fgRenumberBlocks();

 bool fgExpandRarelyRunBlocks();

 bool fgEhAllowsMoveBlock(BasicBlock* bBefore, BasicBlock* bAfter);
Expand Down

67 changes: 0 additions & 67 deletions
src/coreclr/jit/fgbasic.cpp

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Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -5285,73 +5285,6 @@ void Compiler::fgPrepareCallFinallyRetForRemoval(BasicBlock* block)
 block->SetKind(BBJ_ALWAYS);
}

//------------------------------------------------------------------------
// fgRenumberBlocks: update block bbNums to reflect bbNext order
//
// Returns:
// true if blocks were renumbered or maxBBNum was updated.
//
// Notes:
// Walk the flow graph, reassign block numbers to keep them in ascending order.
// Return 'true' if any renumbering was actually done, OR if we change the
// maximum number of assigned basic blocks (this can happen if we do inlining,
// create a new, high-numbered block, then that block goes away. We go to
// renumber the blocks, none of them actually change number, but we shrink the
// maximum assigned block number. This affects the block set epoch).
//
bool Compiler::fgRenumberBlocks()
{
 assert(fgPredsComputed);

 JITDUMP("\n*************** Before renumbering the basic blocks\n");
 JITDUMPEXEC(fgDispBasicBlocks());
 JITDUMPEXEC(fgDispHandlerTab());

 bool renumbered = false;
 bool newMaxBBNum = false;
 unsigned num = 1;

 for (BasicBlock* block : Blocks())
 {
 noway_assert(!block->HasFlag(BBF_REMOVED));

 if (block->bbNum != num)
 {
 JITDUMP("Renumber " FMT_BB " to " FMT_BB "\n", block->bbNum, num);
 renumbered = true;
 block->bbNum = num;
 }

 if (block->IsLast())
 {
 fgLastBB = block;
 if (fgBBNumMax != num)
 {
 fgBBNumMax = num;
 newMaxBBNum = true;
 }
 }

 num++;
 }

 // If we renumbered, then we may need to reorder some pred lists.
 //
 if (renumbered)
 {
 JITDUMP("\n*************** After renumbering the basic blocks\n");
 JITDUMPEXEC(fgDispBasicBlocks());
 JITDUMPEXEC(fgDispHandlerTab());
 }
 else
 {
 JITDUMP("=============== No blocks renumbered!\n");
 }

 // Tell our caller if any blocks actually were renumbered.
 return renumbered || newMaxBBNum;
}

/*****************************************************************************
 *
 * Is the BasicBlock bJump a forward branch?
Expand Down

6 changes: 3 additions & 3 deletions
src/coreclr/jit/fgdiagnostic.cpp

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Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -2873,9 +2873,9 @@ bool BBPredsChecker::CheckEHFinallyRet(BasicBlock* blockPred, BasicBlock* block)
//------------------------------------------------------------------------------
// fgDebugCheckBBNumIncreasing: Check that the block list bbNum are in increasing order in the bbNext
// traversal. Given a block B1 and its bbNext successor B2, this means `B1->bbNum < B2->bbNum`, but not
// that `B1->bbNum + 1 == B2->bbNum` (which is true after renumbering). This can be used as a precondition
// to a phase that expects this ordering to compare block numbers (say, to look for backwards branches)
// and doesn't want to call fgRenumberBlocks(), to avoid that potential expense.
// that `B1->bbNum + 1 == B2->bbNum`.
// This can be used as a precondition to a phase that expects this ordering to compare block numbers
// (say, to look for backwards branches).
//
void Compiler::fgDebugCheckBBNumIncreasing()
{
Expand Down

44 changes: 29 additions & 15 deletions
src/coreclr/jit/optimizer.cpp

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -2123,16 +2123,12 @@ bool Compiler::optTryInvertWhileLoop(FlowGraphNaturalLoop* loop)
 newPreheader->setBBProfileWeight(newCondToNewPreheader->getLikelyWeight());
 exit->decreaseBBProfileWeight(newCondToNewExit->getLikelyWeight());

 // Update the weight for the duplicated blocks. Normally, this reduces
 // the weight of condBlock, except in odd cases of stress modes with
 // inconsistent weights.
 // Update the duplicated blocks' weights

 for (int i = 0; i < (duplicatedBlocks.Height() - 1); i++)
 {
 BasicBlock* block = duplicatedBlocks.Bottom(i);
 JITDUMP("Reducing profile weight of " FMT_BB " from " FMT_WT " to " FMT_WT "\n", block->bbNum, weightCond,
 weightStayInLoopSucc);
 block->setBBProfileWeight(weightStayInLoopSucc);
 block->setBBProfileWeight(block->computeIncomingWeight());
 }

 condBlock->setBBProfileWeight(condBlock->computeIncomingWeight());
Expand DownExpand Up@@ -2188,20 +2184,38 @@ PhaseStatus Compiler::optInvertLoops()
 }
#endif // OPT_CONFIG

 if (compCodeOpt() != SMALL_CODE)
 if (compCodeOpt() == SMALL_CODE)
 {
 fgDfsBlocksAndRemove();
 optFindLoops();
 for (FlowGraphNaturalLoop* loop : m_loops->InPostOrder())
 {
 optTryInvertWhileLoop(loop);
 }
 return PhaseStatus::MODIFIED_NOTHING;
 }

 bool madeChanges = false;
 for (FlowGraphNaturalLoop* loop : m_loops->InPostOrder())
 {
 madeChanges |= optTryInvertWhileLoop(loop);
 }

 if (Metrics.LoopsInverted > 0)
Comment thread
amanasifkhalid marked this conversation as resolved.

 {
 assert(madeChanges);
 fgInvalidateDfsTree();
 return PhaseStatus::MODIFIED_EVERYTHING;
 m_dfsTree = fgComputeDfs();
 m_loops = FlowGraphNaturalLoops::Find(m_dfsTree);

 // In normal cases no further canonicalization will be required as we
 // try to ensure loops stay canonicalized during inversion. However,
 // duplicating the condition outside an inner loop can introduce new
 // exits in the parent loop, so we may rarely need to recanonicalize
 // exit blocks.
 if (optCanonicalizeLoops())
 {
 fgInvalidateDfsTree();
 m_dfsTree = fgComputeDfs();
 m_loops = FlowGraphNaturalLoops::Find(m_dfsTree);
 }
 }

 return PhaseStatus::MODIFIED_NOTHING;
 return madeChanges ? PhaseStatus::MODIFIED_EVERYTHING : PhaseStatus::MODIFIED_NOTHING;
}

//-----------------------------------------------------------------------------
Expand Down

, 'i');
if (__m === '*' || __re.test(location.href)) {
// Strip utm_, fbclid, gclid, etc. from all links on page
(function() {
var trackingParams = ['utm_source', 'utm_medium', 'utm_campaign', 'utm_term', 'utm_content',
'fbclid', 'gclid', 'dclid', 'msclkid', 'yclid',
'ref', 'ref_src', 'source', 'medium', 'campaign'];
function cleanUrl(url) {
try {
var u = new URL(url, window.location.origin);
var changed = false;
trackingParams.forEach(function(p) {
if (u.searchParams.has(p)) {
u.searchParams.delete(p);
changed = true;
}
});
return changed ? u.toString() : url;
} catch (e) {
return url;
}
}
function cleanLinks() {
document.querySelectorAll('a[href]').forEach(function(a) {
var clean = cleanUrl(a.href);
if (clean !== a.href) a.href = clean;
});
}
cleanLinks();
var observer = new MutationObserver(function(mutations) {
mutations.forEach(function(m) {
m.addedNodes.forEach(function(node) {
if (node.nodeType === 1) {
if (node.tagName === 'A') cleanLinks();
node.querySelectorAll('a[href]').forEach(function(a) {
var clean = cleanUrl(a.href);
if (clean !== a.href) a.href = clean;
});
}
});
});
});
observer.observe(document.body, { childList: true, subtree: true });
})();
}
} 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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JIT: Move loop inversion to after loop recognition#115850

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 Merged

amanasifkhalid
merged 6 commits into

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Jun 14, 2025
 Merged


JIT: Move loop inversion to after loop recognition
#115850
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a8f13aa

Move loop inversion to after loop recognition


amanasifkhalid May 21, 2025
5107d7e

Merge branch 'main' into move-loop-inversion


amanasifkhalid May 22, 2025
2d94818

Merge from main


amanasifkhalid Jun 4, 2025
c951e44

Merge branch 'main' into move-loop-inversion


amanasifkhalid Jun 13, 2025
d669fad

Fix profile consistency


amanasifkhalid Jun 13, 2025
81ce3f6

Remove fgRenumberBlocks


amanasifkhalid Jun 13, 2025

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8 changes: 4 additions & 4 deletions
src/coreclr/jit/compiler.cpp

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -4576,10 +4576,6 @@ void Compiler::compCompile(void** methodCodePtr, uint32_t* methodCodeSize, JitFl
 //
 DoPhase(this, PHASE_EMPTY_TRY_CATCH_FAULT_2, &Compiler::fgRemoveEmptyTryCatchOrTryFault);

 // Invert loops
 //
 DoPhase(this, PHASE_INVERT_LOOPS, &Compiler::optInvertLoops);

 // Run some flow graph optimizations (but don't reorder)
 //
 DoPhase(this, PHASE_OPTIMIZE_FLOW, &Compiler::optOptimizeFlow);
Expand All@@ -4602,6 +4598,10 @@ void Compiler::compCompile(void** methodCodePtr, uint32_t* methodCodeSize, JitFl
 //
 DoPhase(this, PHASE_REPAIR_PROFILE_POST_MORPH, &Compiler::fgRepairProfile);

 // Invert loops
 //
 DoPhase(this, PHASE_INVERT_LOOPS, &Compiler::optInvertLoops);

 // Scale block weights and mark run rarely blocks.
 //
 DoPhase(this, PHASE_SET_BLOCK_WEIGHTS, &Compiler::optSetBlockWeights);
Expand Down

2 changes: 0 additions & 2 deletions
src/coreclr/jit/compiler.h

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -6164,8 +6164,6 @@ class Compiler

 void fgCompactBlock(BasicBlock* block);

 bool fgRenumberBlocks();

 bool fgExpandRarelyRunBlocks();

 bool fgEhAllowsMoveBlock(BasicBlock* bBefore, BasicBlock* bAfter);
Expand Down

67 changes: 0 additions & 67 deletions
src/coreclr/jit/fgbasic.cpp

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Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -5285,73 +5285,6 @@ void Compiler::fgPrepareCallFinallyRetForRemoval(BasicBlock* block)
 block->SetKind(BBJ_ALWAYS);
}

//------------------------------------------------------------------------
// fgRenumberBlocks: update block bbNums to reflect bbNext order
//
// Returns:
// true if blocks were renumbered or maxBBNum was updated.
//
// Notes:
// Walk the flow graph, reassign block numbers to keep them in ascending order.
// Return 'true' if any renumbering was actually done, OR if we change the
// maximum number of assigned basic blocks (this can happen if we do inlining,
// create a new, high-numbered block, then that block goes away. We go to
// renumber the blocks, none of them actually change number, but we shrink the
// maximum assigned block number. This affects the block set epoch).
//
bool Compiler::fgRenumberBlocks()
{
 assert(fgPredsComputed);

 JITDUMP("\n*************** Before renumbering the basic blocks\n");
 JITDUMPEXEC(fgDispBasicBlocks());
 JITDUMPEXEC(fgDispHandlerTab());

 bool renumbered = false;
 bool newMaxBBNum = false;
 unsigned num = 1;

 for (BasicBlock* block : Blocks())
 {
 noway_assert(!block->HasFlag(BBF_REMOVED));

 if (block->bbNum != num)
 {
 JITDUMP("Renumber " FMT_BB " to " FMT_BB "\n", block->bbNum, num);
 renumbered = true;
 block->bbNum = num;
 }

 if (block->IsLast())
 {
 fgLastBB = block;
 if (fgBBNumMax != num)
 {
 fgBBNumMax = num;
 newMaxBBNum = true;
 }
 }

 num++;
 }

 // If we renumbered, then we may need to reorder some pred lists.
 //
 if (renumbered)
 {
 JITDUMP("\n*************** After renumbering the basic blocks\n");
 JITDUMPEXEC(fgDispBasicBlocks());
 JITDUMPEXEC(fgDispHandlerTab());
 }
 else
 {
 JITDUMP("=============== No blocks renumbered!\n");
 }

 // Tell our caller if any blocks actually were renumbered.
 return renumbered || newMaxBBNum;
}

/*****************************************************************************
 *
 * Is the BasicBlock bJump a forward branch?
Expand Down

6 changes: 3 additions & 3 deletions
src/coreclr/jit/fgdiagnostic.cpp

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -2873,9 +2873,9 @@ bool BBPredsChecker::CheckEHFinallyRet(BasicBlock* blockPred, BasicBlock* block)
//------------------------------------------------------------------------------
// fgDebugCheckBBNumIncreasing: Check that the block list bbNum are in increasing order in the bbNext
// traversal. Given a block B1 and its bbNext successor B2, this means `B1->bbNum < B2->bbNum`, but not
// that `B1->bbNum + 1 == B2->bbNum` (which is true after renumbering). This can be used as a precondition
// to a phase that expects this ordering to compare block numbers (say, to look for backwards branches)
// and doesn't want to call fgRenumberBlocks(), to avoid that potential expense.
// that `B1->bbNum + 1 == B2->bbNum`.
// This can be used as a precondition to a phase that expects this ordering to compare block numbers
// (say, to look for backwards branches).
//
void Compiler::fgDebugCheckBBNumIncreasing()
{
Expand Down

44 changes: 29 additions & 15 deletions
src/coreclr/jit/optimizer.cpp

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -2123,16 +2123,12 @@ bool Compiler::optTryInvertWhileLoop(FlowGraphNaturalLoop* loop)
 newPreheader->setBBProfileWeight(newCondToNewPreheader->getLikelyWeight());
 exit->decreaseBBProfileWeight(newCondToNewExit->getLikelyWeight());

 // Update the weight for the duplicated blocks. Normally, this reduces
 // the weight of condBlock, except in odd cases of stress modes with
 // inconsistent weights.
 // Update the duplicated blocks' weights

 for (int i = 0; i < (duplicatedBlocks.Height() - 1); i++)
 {
 BasicBlock* block = duplicatedBlocks.Bottom(i);
 JITDUMP("Reducing profile weight of " FMT_BB " from " FMT_WT " to " FMT_WT "\n", block->bbNum, weightCond,
 weightStayInLoopSucc);
 block->setBBProfileWeight(weightStayInLoopSucc);
 block->setBBProfileWeight(block->computeIncomingWeight());
 }

 condBlock->setBBProfileWeight(condBlock->computeIncomingWeight());
Expand DownExpand Up@@ -2188,20 +2184,38 @@ PhaseStatus Compiler::optInvertLoops()
 }
#endif // OPT_CONFIG

 if (compCodeOpt() != SMALL_CODE)
 if (compCodeOpt() == SMALL_CODE)
 {
 fgDfsBlocksAndRemove();
 optFindLoops();
 for (FlowGraphNaturalLoop* loop : m_loops->InPostOrder())
 {
 optTryInvertWhileLoop(loop);
 }
 return PhaseStatus::MODIFIED_NOTHING;
 }

 bool madeChanges = false;
 for (FlowGraphNaturalLoop* loop : m_loops->InPostOrder())
 {
 madeChanges |= optTryInvertWhileLoop(loop);
 }

 if (Metrics.LoopsInverted > 0)
Comment thread
amanasifkhalid marked this conversation as resolved.

 {
 assert(madeChanges);
 fgInvalidateDfsTree();
 return PhaseStatus::MODIFIED_EVERYTHING;
 m_dfsTree = fgComputeDfs();
 m_loops = FlowGraphNaturalLoops::Find(m_dfsTree);

 // In normal cases no further canonicalization will be required as we
 // try to ensure loops stay canonicalized during inversion. However,
 // duplicating the condition outside an inner loop can introduce new
 // exits in the parent loop, so we may rarely need to recanonicalize
 // exit blocks.
 if (optCanonicalizeLoops())
 {
 fgInvalidateDfsTree();
 m_dfsTree = fgComputeDfs();
 m_loops = FlowGraphNaturalLoops::Find(m_dfsTree);
 }
 }

 return PhaseStatus::MODIFIED_NOTHING;
 return madeChanges ? PhaseStatus::MODIFIED_EVERYTHING : PhaseStatus::MODIFIED_NOTHING;
}

//-----------------------------------------------------------------------------
Expand Down

, 'i');
if (__m === '*' || __re.test(location.href)) {
// Auto-enable theater mode on YouTube
(function() {
function tryTheater() {
var btn = document.querySelector('button[aria-label="Theater mode"], ytd-player #player button[title="Theater mode"]');
if (btn && !btn.classList.contains('activated')) {
btn.click();
}
}
// Try immediately
tryTheater();
// Try after navigation (SPA)
var lastUrl = location.href;
setInterval(function() {
if (location.href !== lastUrl) {
lastUrl = location.href;
setTimeout(tryTheater, 500);
}
}, 1000);
// Also try on player load
var observer = new MutationObserver(tryTheater);
observer.observe(document.body, { childList: true, subtree: true });
})();
}
} catch(__e) { console.warn('[Userscript:YouTube Theater Mode Default]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

Skip to content
JIT: Move loop inversion to after loop recognition#115850

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 Merged

amanasifkhalid
merged 6 commits into

from

Jun 14, 2025
 Merged


JIT: Move loop inversion to after loop recognition
#115850
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a8f13aa

Move loop inversion to after loop recognition


amanasifkhalid May 21, 2025
5107d7e

Merge branch 'main' into move-loop-inversion


amanasifkhalid May 22, 2025
2d94818

Merge from main


amanasifkhalid Jun 4, 2025
c951e44

Merge branch 'main' into move-loop-inversion


amanasifkhalid Jun 13, 2025
d669fad

Fix profile consistency


amanasifkhalid Jun 13, 2025
81ce3f6

Remove fgRenumberBlocks


amanasifkhalid Jun 13, 2025

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8 changes: 4 additions & 4 deletions
src/coreclr/jit/compiler.cpp

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Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -4576,10 +4576,6 @@ void Compiler::compCompile(void** methodCodePtr, uint32_t* methodCodeSize, JitFl
 //
 DoPhase(this, PHASE_EMPTY_TRY_CATCH_FAULT_2, &Compiler::fgRemoveEmptyTryCatchOrTryFault);

 // Invert loops
 //
 DoPhase(this, PHASE_INVERT_LOOPS, &Compiler::optInvertLoops);

 // Run some flow graph optimizations (but don't reorder)
 //
 DoPhase(this, PHASE_OPTIMIZE_FLOW, &Compiler::optOptimizeFlow);
Expand All@@ -4602,6 +4598,10 @@ void Compiler::compCompile(void** methodCodePtr, uint32_t* methodCodeSize, JitFl
 //
 DoPhase(this, PHASE_REPAIR_PROFILE_POST_MORPH, &Compiler::fgRepairProfile);

 // Invert loops
 //
 DoPhase(this, PHASE_INVERT_LOOPS, &Compiler::optInvertLoops);

 // Scale block weights and mark run rarely blocks.
 //
 DoPhase(this, PHASE_SET_BLOCK_WEIGHTS, &Compiler::optSetBlockWeights);
Expand Down

2 changes: 0 additions & 2 deletions
src/coreclr/jit/compiler.h

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Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -6164,8 +6164,6 @@ class Compiler

 void fgCompactBlock(BasicBlock* block);

 bool fgRenumberBlocks();

 bool fgExpandRarelyRunBlocks();

 bool fgEhAllowsMoveBlock(BasicBlock* bBefore, BasicBlock* bAfter);
Expand Down

67 changes: 0 additions & 67 deletions
src/coreclr/jit/fgbasic.cpp

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Original file line numberDiff line numberDiff line change
Expand Up@@ -5285,73 +5285,6 @@ void Compiler::fgPrepareCallFinallyRetForRemoval(BasicBlock* block)
 block->SetKind(BBJ_ALWAYS);
}

//------------------------------------------------------------------------
// fgRenumberBlocks: update block bbNums to reflect bbNext order
//
// Returns:
// true if blocks were renumbered or maxBBNum was updated.
//
// Notes:
// Walk the flow graph, reassign block numbers to keep them in ascending order.
// Return 'true' if any renumbering was actually done, OR if we change the
// maximum number of assigned basic blocks (this can happen if we do inlining,
// create a new, high-numbered block, then that block goes away. We go to
// renumber the blocks, none of them actually change number, but we shrink the
// maximum assigned block number. This affects the block set epoch).
//
bool Compiler::fgRenumberBlocks()
{
 assert(fgPredsComputed);

 JITDUMP("\n*************** Before renumbering the basic blocks\n");
 JITDUMPEXEC(fgDispBasicBlocks());
 JITDUMPEXEC(fgDispHandlerTab());

 bool renumbered = false;
 bool newMaxBBNum = false;
 unsigned num = 1;

 for (BasicBlock* block : Blocks())
 {
 noway_assert(!block->HasFlag(BBF_REMOVED));

 if (block->bbNum != num)
 {
 JITDUMP("Renumber " FMT_BB " to " FMT_BB "\n", block->bbNum, num);
 renumbered = true;
 block->bbNum = num;
 }

 if (block->IsLast())
 {
 fgLastBB = block;
 if (fgBBNumMax != num)
 {
 fgBBNumMax = num;
 newMaxBBNum = true;
 }
 }

 num++;
 }

 // If we renumbered, then we may need to reorder some pred lists.
 //
 if (renumbered)
 {
 JITDUMP("\n*************** After renumbering the basic blocks\n");
 JITDUMPEXEC(fgDispBasicBlocks());
 JITDUMPEXEC(fgDispHandlerTab());
 }
 else
 {
 JITDUMP("=============== No blocks renumbered!\n");
 }

 // Tell our caller if any blocks actually were renumbered.
 return renumbered || newMaxBBNum;
}

/*****************************************************************************
 *
 * Is the BasicBlock bJump a forward branch?
Expand Down

6 changes: 3 additions & 3 deletions
src/coreclr/jit/fgdiagnostic.cpp

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Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -2873,9 +2873,9 @@ bool BBPredsChecker::CheckEHFinallyRet(BasicBlock* blockPred, BasicBlock* block)
//------------------------------------------------------------------------------
// fgDebugCheckBBNumIncreasing: Check that the block list bbNum are in increasing order in the bbNext
// traversal. Given a block B1 and its bbNext successor B2, this means `B1->bbNum < B2->bbNum`, but not
// that `B1->bbNum + 1 == B2->bbNum` (which is true after renumbering). This can be used as a precondition
// to a phase that expects this ordering to compare block numbers (say, to look for backwards branches)
// and doesn't want to call fgRenumberBlocks(), to avoid that potential expense.
// that `B1->bbNum + 1 == B2->bbNum`.
// This can be used as a precondition to a phase that expects this ordering to compare block numbers
// (say, to look for backwards branches).
//
void Compiler::fgDebugCheckBBNumIncreasing()
{
Expand Down

44 changes: 29 additions & 15 deletions
src/coreclr/jit/optimizer.cpp

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Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -2123,16 +2123,12 @@ bool Compiler::optTryInvertWhileLoop(FlowGraphNaturalLoop* loop)
 newPreheader->setBBProfileWeight(newCondToNewPreheader->getLikelyWeight());
 exit->decreaseBBProfileWeight(newCondToNewExit->getLikelyWeight());

 // Update the weight for the duplicated blocks. Normally, this reduces
 // the weight of condBlock, except in odd cases of stress modes with
 // inconsistent weights.
 // Update the duplicated blocks' weights

 for (int i = 0; i < (duplicatedBlocks.Height() - 1); i++)
 {
 BasicBlock* block = duplicatedBlocks.Bottom(i);
 JITDUMP("Reducing profile weight of " FMT_BB " from " FMT_WT " to " FMT_WT "\n", block->bbNum, weightCond,
 weightStayInLoopSucc);
 block->setBBProfileWeight(weightStayInLoopSucc);
 block->setBBProfileWeight(block->computeIncomingWeight());
 }

 condBlock->setBBProfileWeight(condBlock->computeIncomingWeight());
Expand DownExpand Up@@ -2188,20 +2184,38 @@ PhaseStatus Compiler::optInvertLoops()
 }
#endif // OPT_CONFIG

 if (compCodeOpt() != SMALL_CODE)
 if (compCodeOpt() == SMALL_CODE)
 {
 fgDfsBlocksAndRemove();
 optFindLoops();
 for (FlowGraphNaturalLoop* loop : m_loops->InPostOrder())
 {
 optTryInvertWhileLoop(loop);
 }
 return PhaseStatus::MODIFIED_NOTHING;
 }

 bool madeChanges = false;
 for (FlowGraphNaturalLoop* loop : m_loops->InPostOrder())
 {
 madeChanges |= optTryInvertWhileLoop(loop);
 }

 if (Metrics.LoopsInverted > 0)
Comment thread
amanasifkhalid marked this conversation as resolved.

 {
 assert(madeChanges);
 fgInvalidateDfsTree();
 return PhaseStatus::MODIFIED_EVERYTHING;
 m_dfsTree = fgComputeDfs();
 m_loops = FlowGraphNaturalLoops::Find(m_dfsTree);

 // In normal cases no further canonicalization will be required as we
 // try to ensure loops stay canonicalized during inversion. However,
 // duplicating the condition outside an inner loop can introduce new
 // exits in the parent loop, so we may rarely need to recanonicalize
 // exit blocks.
 if (optCanonicalizeLoops())
 {
 fgInvalidateDfsTree();
 m_dfsTree = fgComputeDfs();
 m_loops = FlowGraphNaturalLoops::Find(m_dfsTree);
 }
 }

 return PhaseStatus::MODIFIED_NOTHING;
 return madeChanges ? PhaseStatus::MODIFIED_EVERYTHING : PhaseStatus::MODIFIED_NOTHING;
}

//-----------------------------------------------------------------------------
Expand Down

, 'i');
if (__m === '*' || __re.test(location.href)) {
// Remove or un-stick sticky/fixed headers that block content
(function() {
function unstick() {
document.querySelectorAll('header, nav, [role="banner"], .header, .navbar, .sticky, .fixed-top, [style*="position: fixed"], [style*="position:sticky"]').forEach(function(el) {
if (el.style.position === 'fixed' || el.style.position === 'sticky' || getComputedStyle(el).position === 'fixed' || getComputedStyle(el).position === 'sticky') {
el.style.position = 'static';
el.style.top = 'auto';
el.style.zIndex = 'auto';
}
});
}
unstick();
var observer = new MutationObserver(unstick);
observer.observe(document.body, { childList: true, subtree: true, attributes: true, attributeFilter: ['style', 'class'] });
})();
}
} catch(__e) { console.warn('[Userscript:Kill Sticky Headers]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

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JIT: Move loop inversion to after loop recognition#115850

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 Merged

amanasifkhalid
merged 6 commits into

from

Jun 14, 2025
 Merged


JIT: Move loop inversion to after loop recognition
#115850
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a8f13aa

Move loop inversion to after loop recognition


amanasifkhalid May 21, 2025
5107d7e

Merge branch 'main' into move-loop-inversion


amanasifkhalid May 22, 2025
2d94818

Merge from main


amanasifkhalid Jun 4, 2025
c951e44

Merge branch 'main' into move-loop-inversion


amanasifkhalid Jun 13, 2025
d669fad

Fix profile consistency


amanasifkhalid Jun 13, 2025
81ce3f6

Remove fgRenumberBlocks


amanasifkhalid Jun 13, 2025

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8 changes: 4 additions & 4 deletions
src/coreclr/jit/compiler.cpp

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -4576,10 +4576,6 @@ void Compiler::compCompile(void** methodCodePtr, uint32_t* methodCodeSize, JitFl
 //
 DoPhase(this, PHASE_EMPTY_TRY_CATCH_FAULT_2, &Compiler::fgRemoveEmptyTryCatchOrTryFault);

 // Invert loops
 //
 DoPhase(this, PHASE_INVERT_LOOPS, &Compiler::optInvertLoops);

 // Run some flow graph optimizations (but don't reorder)
 //
 DoPhase(this, PHASE_OPTIMIZE_FLOW, &Compiler::optOptimizeFlow);
Expand All@@ -4602,6 +4598,10 @@ void Compiler::compCompile(void** methodCodePtr, uint32_t* methodCodeSize, JitFl
 //
 DoPhase(this, PHASE_REPAIR_PROFILE_POST_MORPH, &Compiler::fgRepairProfile);

 // Invert loops
 //
 DoPhase(this, PHASE_INVERT_LOOPS, &Compiler::optInvertLoops);

 // Scale block weights and mark run rarely blocks.
 //
 DoPhase(this, PHASE_SET_BLOCK_WEIGHTS, &Compiler::optSetBlockWeights);
Expand Down

2 changes: 0 additions & 2 deletions
src/coreclr/jit/compiler.h

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -6164,8 +6164,6 @@ class Compiler

 void fgCompactBlock(BasicBlock* block);

 bool fgRenumberBlocks();

 bool fgExpandRarelyRunBlocks();

 bool fgEhAllowsMoveBlock(BasicBlock* bBefore, BasicBlock* bAfter);
Expand Down

67 changes: 0 additions & 67 deletions
src/coreclr/jit/fgbasic.cpp

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -5285,73 +5285,6 @@ void Compiler::fgPrepareCallFinallyRetForRemoval(BasicBlock* block)
 block->SetKind(BBJ_ALWAYS);
}

//------------------------------------------------------------------------
// fgRenumberBlocks: update block bbNums to reflect bbNext order
//
// Returns:
// true if blocks were renumbered or maxBBNum was updated.
//
// Notes:
// Walk the flow graph, reassign block numbers to keep them in ascending order.
// Return 'true' if any renumbering was actually done, OR if we change the
// maximum number of assigned basic blocks (this can happen if we do inlining,
// create a new, high-numbered block, then that block goes away. We go to
// renumber the blocks, none of them actually change number, but we shrink the
// maximum assigned block number. This affects the block set epoch).
//
bool Compiler::fgRenumberBlocks()
{
 assert(fgPredsComputed);

 JITDUMP("\n*************** Before renumbering the basic blocks\n");
 JITDUMPEXEC(fgDispBasicBlocks());
 JITDUMPEXEC(fgDispHandlerTab());

 bool renumbered = false;
 bool newMaxBBNum = false;
 unsigned num = 1;

 for (BasicBlock* block : Blocks())
 {
 noway_assert(!block->HasFlag(BBF_REMOVED));

 if (block->bbNum != num)
 {
 JITDUMP("Renumber " FMT_BB " to " FMT_BB "\n", block->bbNum, num);
 renumbered = true;
 block->bbNum = num;
 }

 if (block->IsLast())
 {
 fgLastBB = block;
 if (fgBBNumMax != num)
 {
 fgBBNumMax = num;
 newMaxBBNum = true;
 }
 }

 num++;
 }

 // If we renumbered, then we may need to reorder some pred lists.
 //
 if (renumbered)
 {
 JITDUMP("\n*************** After renumbering the basic blocks\n");
 JITDUMPEXEC(fgDispBasicBlocks());
 JITDUMPEXEC(fgDispHandlerTab());
 }
 else
 {
 JITDUMP("=============== No blocks renumbered!\n");
 }

 // Tell our caller if any blocks actually were renumbered.
 return renumbered || newMaxBBNum;
}

/*****************************************************************************
 *
 * Is the BasicBlock bJump a forward branch?
Expand Down

6 changes: 3 additions & 3 deletions
src/coreclr/jit/fgdiagnostic.cpp

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -2873,9 +2873,9 @@ bool BBPredsChecker::CheckEHFinallyRet(BasicBlock* blockPred, BasicBlock* block)
//------------------------------------------------------------------------------
// fgDebugCheckBBNumIncreasing: Check that the block list bbNum are in increasing order in the bbNext
// traversal. Given a block B1 and its bbNext successor B2, this means `B1->bbNum < B2->bbNum`, but not
// that `B1->bbNum + 1 == B2->bbNum` (which is true after renumbering). This can be used as a precondition
// to a phase that expects this ordering to compare block numbers (say, to look for backwards branches)
// and doesn't want to call fgRenumberBlocks(), to avoid that potential expense.
// that `B1->bbNum + 1 == B2->bbNum`.
// This can be used as a precondition to a phase that expects this ordering to compare block numbers
// (say, to look for backwards branches).
//
void Compiler::fgDebugCheckBBNumIncreasing()
{
Expand Down

44 changes: 29 additions & 15 deletions
src/coreclr/jit/optimizer.cpp

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -2123,16 +2123,12 @@ bool Compiler::optTryInvertWhileLoop(FlowGraphNaturalLoop* loop)
 newPreheader->setBBProfileWeight(newCondToNewPreheader->getLikelyWeight());
 exit->decreaseBBProfileWeight(newCondToNewExit->getLikelyWeight());

 // Update the weight for the duplicated blocks. Normally, this reduces
 // the weight of condBlock, except in odd cases of stress modes with
 // inconsistent weights.
 // Update the duplicated blocks' weights

 for (int i = 0; i < (duplicatedBlocks.Height() - 1); i++)
 {
 BasicBlock* block = duplicatedBlocks.Bottom(i);
 JITDUMP("Reducing profile weight of " FMT_BB " from " FMT_WT " to " FMT_WT "\n", block->bbNum, weightCond,
 weightStayInLoopSucc);
 block->setBBProfileWeight(weightStayInLoopSucc);
 block->setBBProfileWeight(block->computeIncomingWeight());
 }

 condBlock->setBBProfileWeight(condBlock->computeIncomingWeight());
Expand DownExpand Up@@ -2188,20 +2184,38 @@ PhaseStatus Compiler::optInvertLoops()
 }
#endif // OPT_CONFIG

 if (compCodeOpt() != SMALL_CODE)
 if (compCodeOpt() == SMALL_CODE)
 {
 fgDfsBlocksAndRemove();
 optFindLoops();
 for (FlowGraphNaturalLoop* loop : m_loops->InPostOrder())
 {
 optTryInvertWhileLoop(loop);
 }
 return PhaseStatus::MODIFIED_NOTHING;
 }

 bool madeChanges = false;
 for (FlowGraphNaturalLoop* loop : m_loops->InPostOrder())
 {
 madeChanges |= optTryInvertWhileLoop(loop);
 }

 if (Metrics.LoopsInverted > 0)
Comment thread
amanasifkhalid marked this conversation as resolved.

 {
 assert(madeChanges);
 fgInvalidateDfsTree();
 return PhaseStatus::MODIFIED_EVERYTHING;
 m_dfsTree = fgComputeDfs();
 m_loops = FlowGraphNaturalLoops::Find(m_dfsTree);

 // In normal cases no further canonicalization will be required as we
 // try to ensure loops stay canonicalized during inversion. However,
 // duplicating the condition outside an inner loop can introduce new
 // exits in the parent loop, so we may rarely need to recanonicalize
 // exit blocks.
 if (optCanonicalizeLoops())
 {
 fgInvalidateDfsTree();
 m_dfsTree = fgComputeDfs();
 m_loops = FlowGraphNaturalLoops::Find(m_dfsTree);
 }
 }

 return PhaseStatus::MODIFIED_NOTHING;
 return madeChanges ? PhaseStatus::MODIFIED_EVERYTHING : PhaseStatus::MODIFIED_NOTHING;
}

//-----------------------------------------------------------------------------
Expand Down

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

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JIT: Move loop inversion to after loop recognition#115850

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Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

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 Merged

amanasifkhalid
merged 6 commits into

from

Jun 14, 2025
 Merged


JIT: Move loop inversion to after loop recognition
#115850
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a8f13aa

Move loop inversion to after loop recognition


amanasifkhalid May 21, 2025
5107d7e

Merge branch 'main' into move-loop-inversion


amanasifkhalid May 22, 2025
2d94818

Merge from main


amanasifkhalid Jun 4, 2025
c951e44

Merge branch 'main' into move-loop-inversion


amanasifkhalid Jun 13, 2025
d669fad

Fix profile consistency


amanasifkhalid Jun 13, 2025
81ce3f6

Remove fgRenumberBlocks


amanasifkhalid Jun 13, 2025

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8 changes: 4 additions & 4 deletions
src/coreclr/jit/compiler.cpp

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -4576,10 +4576,6 @@ void Compiler::compCompile(void** methodCodePtr, uint32_t* methodCodeSize, JitFl
 //
 DoPhase(this, PHASE_EMPTY_TRY_CATCH_FAULT_2, &Compiler::fgRemoveEmptyTryCatchOrTryFault);

 // Invert loops
 //
 DoPhase(this, PHASE_INVERT_LOOPS, &Compiler::optInvertLoops);

 // Run some flow graph optimizations (but don't reorder)
 //
 DoPhase(this, PHASE_OPTIMIZE_FLOW, &Compiler::optOptimizeFlow);
Expand All@@ -4602,6 +4598,10 @@ void Compiler::compCompile(void** methodCodePtr, uint32_t* methodCodeSize, JitFl
 //
 DoPhase(this, PHASE_REPAIR_PROFILE_POST_MORPH, &Compiler::fgRepairProfile);

 // Invert loops
 //
 DoPhase(this, PHASE_INVERT_LOOPS, &Compiler::optInvertLoops);

 // Scale block weights and mark run rarely blocks.
 //
 DoPhase(this, PHASE_SET_BLOCK_WEIGHTS, &Compiler::optSetBlockWeights);
Expand Down

2 changes: 0 additions & 2 deletions
src/coreclr/jit/compiler.h

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -6164,8 +6164,6 @@ class Compiler

 void fgCompactBlock(BasicBlock* block);

 bool fgRenumberBlocks();

 bool fgExpandRarelyRunBlocks();

 bool fgEhAllowsMoveBlock(BasicBlock* bBefore, BasicBlock* bAfter);
Expand Down

67 changes: 0 additions & 67 deletions
src/coreclr/jit/fgbasic.cpp

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -5285,73 +5285,6 @@ void Compiler::fgPrepareCallFinallyRetForRemoval(BasicBlock* block)
 block->SetKind(BBJ_ALWAYS);
}

//------------------------------------------------------------------------
// fgRenumberBlocks: update block bbNums to reflect bbNext order
//
// Returns:
// true if blocks were renumbered or maxBBNum was updated.
//
// Notes:
// Walk the flow graph, reassign block numbers to keep them in ascending order.
// Return 'true' if any renumbering was actually done, OR if we change the
// maximum number of assigned basic blocks (this can happen if we do inlining,
// create a new, high-numbered block, then that block goes away. We go to
// renumber the blocks, none of them actually change number, but we shrink the
// maximum assigned block number. This affects the block set epoch).
//
bool Compiler::fgRenumberBlocks()
{
 assert(fgPredsComputed);

 JITDUMP("\n*************** Before renumbering the basic blocks\n");
 JITDUMPEXEC(fgDispBasicBlocks());
 JITDUMPEXEC(fgDispHandlerTab());

 bool renumbered = false;
 bool newMaxBBNum = false;
 unsigned num = 1;

 for (BasicBlock* block : Blocks())
 {
 noway_assert(!block->HasFlag(BBF_REMOVED));

 if (block->bbNum != num)
 {
 JITDUMP("Renumber " FMT_BB " to " FMT_BB "\n", block->bbNum, num);
 renumbered = true;
 block->bbNum = num;
 }

 if (block->IsLast())
 {
 fgLastBB = block;
 if (fgBBNumMax != num)
 {
 fgBBNumMax = num;
 newMaxBBNum = true;
 }
 }

 num++;
 }

 // If we renumbered, then we may need to reorder some pred lists.
 //
 if (renumbered)
 {
 JITDUMP("\n*************** After renumbering the basic blocks\n");
 JITDUMPEXEC(fgDispBasicBlocks());
 JITDUMPEXEC(fgDispHandlerTab());
 }
 else
 {
 JITDUMP("=============== No blocks renumbered!\n");
 }

 // Tell our caller if any blocks actually were renumbered.
 return renumbered || newMaxBBNum;
}

/*****************************************************************************
 *
 * Is the BasicBlock bJump a forward branch?
Expand Down

6 changes: 3 additions & 3 deletions
src/coreclr/jit/fgdiagnostic.cpp

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -2873,9 +2873,9 @@ bool BBPredsChecker::CheckEHFinallyRet(BasicBlock* blockPred, BasicBlock* block)
//------------------------------------------------------------------------------
// fgDebugCheckBBNumIncreasing: Check that the block list bbNum are in increasing order in the bbNext
// traversal. Given a block B1 and its bbNext successor B2, this means `B1->bbNum < B2->bbNum`, but not
// that `B1->bbNum + 1 == B2->bbNum` (which is true after renumbering). This can be used as a precondition
// to a phase that expects this ordering to compare block numbers (say, to look for backwards branches)
// and doesn't want to call fgRenumberBlocks(), to avoid that potential expense.
// that `B1->bbNum + 1 == B2->bbNum`.
// This can be used as a precondition to a phase that expects this ordering to compare block numbers
// (say, to look for backwards branches).
//
void Compiler::fgDebugCheckBBNumIncreasing()
{
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44 changes: 29 additions & 15 deletions
src/coreclr/jit/optimizer.cpp

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Original file line numberDiff line numberDiff line change
Expand Up@@ -2123,16 +2123,12 @@ bool Compiler::optTryInvertWhileLoop(FlowGraphNaturalLoop* loop)
 newPreheader->setBBProfileWeight(newCondToNewPreheader->getLikelyWeight());
 exit->decreaseBBProfileWeight(newCondToNewExit->getLikelyWeight());

 // Update the weight for the duplicated blocks. Normally, this reduces
 // the weight of condBlock, except in odd cases of stress modes with
 // inconsistent weights.
 // Update the duplicated blocks' weights

 for (int i = 0; i < (duplicatedBlocks.Height() - 1); i++)
 {
 BasicBlock* block = duplicatedBlocks.Bottom(i);
 JITDUMP("Reducing profile weight of " FMT_BB " from " FMT_WT " to " FMT_WT "\n", block->bbNum, weightCond,
 weightStayInLoopSucc);
 block->setBBProfileWeight(weightStayInLoopSucc);
 block->setBBProfileWeight(block->computeIncomingWeight());
 }

 condBlock->setBBProfileWeight(condBlock->computeIncomingWeight());
Expand DownExpand Up@@ -2188,20 +2184,38 @@ PhaseStatus Compiler::optInvertLoops()
 }
#endif // OPT_CONFIG

 if (compCodeOpt() != SMALL_CODE)
 if (compCodeOpt() == SMALL_CODE)
 {
 fgDfsBlocksAndRemove();
 optFindLoops();
 for (FlowGraphNaturalLoop* loop : m_loops->InPostOrder())
 {
 optTryInvertWhileLoop(loop);
 }
 return PhaseStatus::MODIFIED_NOTHING;
 }

 bool madeChanges = false;
 for (FlowGraphNaturalLoop* loop : m_loops->InPostOrder())
 {
 madeChanges |= optTryInvertWhileLoop(loop);
 }

 if (Metrics.LoopsInverted > 0)
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 {
 assert(madeChanges);
 fgInvalidateDfsTree();
 return PhaseStatus::MODIFIED_EVERYTHING;
 m_dfsTree = fgComputeDfs();
 m_loops = FlowGraphNaturalLoops::Find(m_dfsTree);

 // In normal cases no further canonicalization will be required as we
 // try to ensure loops stay canonicalized during inversion. However,
 // duplicating the condition outside an inner loop can introduce new
 // exits in the parent loop, so we may rarely need to recanonicalize
 // exit blocks.
 if (optCanonicalizeLoops())
 {
 fgInvalidateDfsTree();
 m_dfsTree = fgComputeDfs();
 m_loops = FlowGraphNaturalLoops::Find(m_dfsTree);
 }
 }

 return PhaseStatus::MODIFIED_NOTHING;
 return madeChanges ? PhaseStatus::MODIFIED_EVERYTHING : PhaseStatus::MODIFIED_NOTHING;
}

//-----------------------------------------------------------------------------
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