Manuel Carrasco ee6f5f386f

[InstCombine] Replace alloca with undef size with poison instead of null (#182919) ...

InstCombine previously replaced an alloca instruction with a null
pointer when the array size operand was undef. While this replacement
may be legal, it still caused invalid IR in cases where the original
alloca was used by `@llvm.lifetime` intrinsics.

The spec requires that the pointer operand of `@llvm.lifetime.*` must be
either:

- a pointer to an alloca instruction, or
- a poison value.

Replacing the pointer with null violated this requirement and triggered
verifier errors.

These new changes update InstCombine so that in this scenario the alloca
is replaced with poison instead of null.

2026-02-27 19:13:57 +00:00

..

CMakeLists.txt

…

InstCombineAddSub.cpp

[InstCombine] Preserve fdiv metadata on fneg folds (#179157)

2026-02-03 08:27:18 +08:00

InstCombineAndOrXor.cpp

AMDGPU: Strip sign bit operations on llvm.amdgcn.trig.preop uses (#179712)

2026-02-19 18:44:33 +01:00

InstCombineAtomicRMW.cpp

[NFC][InstCombine] Fix namespace usage in InstCombine (#161902)

2025-10-04 05:28:24 -07:00

InstCombineCalls.cpp

[InstCombine] Combine extract from get_active_lane_mask where all lanes inactive (#183329)

2026-02-27 09:46:49 +00:00

InstCombineCasts.cpp

InstCombine: Fold bitcast of vector with constant to scalar (#179042)

2026-02-19 21:35:31 +01:00

InstCombineCompares.cpp

[InstCombine] Fold shift of boolean zext to logic sequence (#180596)

2026-02-26 14:29:15 +01:00

InstCombineInternal.h

[InstCombine] Optimise the expression (C && A) || (!C && B) with FoldOrOfLogicalAnds (#178438)

2026-02-16 01:08:30 +05:30

InstCombineLoadStoreAlloca.cpp

[InstCombine] Replace alloca with undef size with poison instead of null (#182919)

2026-02-27 19:13:57 +00:00

InstCombineMulDivRem.cpp

InstCombine: Use SimplifyDemandedFPClass on fmul (#177490)

2026-02-10 09:49:31 +00:00

InstCombineNegator.cpp

[InstCombine] Optimize sub(sext(add(x,y)),sext(add(x,z))). (#144174)

2025-06-19 10:13:58 -07:00

InstCombinePHI.cpp

[InstCombine] Avoid invalid bitcast across address spaces in foldIntegerTypedPHI (#181064)

2026-02-15 15:35:43 -08:00

InstCombineSelect.cpp

InstCombine: Fold absorbing fmul of compared 0 into select (#172381)

2026-02-21 18:42:09 +00:00

InstCombineShifts.cpp

[InstCombine] Fix crash on large integers in visitShl (#176723)

2026-01-19 12:07:03 +01:00

InstCombineSimplifyDemanded.cpp

InstCombine: Implement SimplifyDemandedFPClass for ldexp (#180703)

2026-02-19 10:24:46 +00:00

InstCombineVectorOps.cpp

[InstCombine] Limit canonicalization of extractelement(cast) to constant index or same basic block (#166227)

2026-01-08 22:43:13 +01:00

InstructionCombining.cpp

[InstCombine] Only ignore first zero index during GEP canonicalization (#180764)

2026-02-23 08:55:00 +00:00