Implement remaining ILGenertorImpl methods, excluding scope. Add max stack calculation for branching.

[buyaa-n]

• Adding implementations for Emit(OpCode opcode, SignatureHelper signature), EmitCalli(OpCode opcode, CallingConvention unmanagedCallConv, Type? returnType, Type[]? parameterTypes) and EmitCalli(OpCode opcode, CallingConventions callingConvention, Type? returnType, Type[]? parameterTypes, Type[]? optionalParameterTypes)
• Refactored member reference logic completely to cover method+optionalParameters reference scenario, also refactored/fixed all ModuleBuilder.Get***MetadataToken implementations as needed
• No-op (instead of throwing NotImplementedException) for BeginScope(), EndScope() and UsingNamespace(string usingNamespace), their implementations will be added with PDB support.
• Refactored max stack calculation to account forward and backward branching (followed the runtime approach and imported tests), switch casing etc and test
• Fixed the bug that was causing BadImageFormatException when loading generated assemblies with Assembly.LoadFrom(path) for run. Some tests now run the loaded assembly.

Contributes to #92975

[ghost]

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Issue Details

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• Adding implementations for Emit(OpCode opcode, SignatureHelper signature), EmitCalli(OpCode opcode, CallingConvention unmanagedCallConv, Type? returnType, Type[]? parameterTypes) and EmitCalli(OpCode opcode, CallingConventions callingConvention, Type? returnType, Type[]? parameterTypes, Type[]? optionalParameterTypes)
• Refactored member reference logic completely to cover method+optionalParameters reference scenario, also refactored/fixed all ModuleBuilder.Get***MetadataToken implementations as needed
• No-op (instead of throwing NotImplementedException) for BeginScope(), EndScope() and UsingNamespace(string usingNamespace), their implementations will be added with PDB support.
• Refactored max stack calculation to account forward and backward branching, switch casing etc and test
• Fixed the bug that was causing BadImageFormatException when loading generated assemblies with Assembly.LoadFrom(path) for run. Some tests no run the loaded assembly.

Contributes to #92975

Author:	buyaa-n
Assignees:	-
Labels:	area-System.Reflection.Emit
Milestone:	-

[steveharter]

LGTM; minor comments \ questions, Although there is a test failure related to this PR.

[steveharter]

Why not throw NIE?

[steveharter]

So we don't detect \ throw on these cases, and CreateTypeInfo() doesn't either?

[buyaa-n]

These tests are imported from runtime ILGenerator tests

runtime/src/libraries/System.Reflection.Emit.ILGeneration/tests/ILGenerator/Emit5Tests.cs

Lines 250 to 251 in 9e57b6a

	// The label is marked with a larger stack depth, one. This IL is invalid.
	ilg.Emit(OpCodes.Ldc_I4_1);

Personally, I am not sure this exact test makes sense, though runtime doesn't detect or throw ...

[steveharter]

Note the test error: AssemblySaveILGeneratorTests.SimpleForLoopTest has failed.