FYLGQ 764457a6e9

[InstCombine] Fold cmp of select-of-constants via truth table (#186591) ...

This patch adds a generic InstCombine fold for:
cmp pred (select C1, TV1, FV1), (select C2, TV2, FV2)
when all select arms are constants and the comparison can be
constant-folded for all four combinations of C1/C2. The fold computes a
4-entry truth table and synthesizes a boolean expression using
createLogicFromTable.
This generalizes patterns like:
fcmp une (select C1, -1.0, 1.0), (select C2, -1.0, 1.0) -> xor C1, C2
The transform bails out for mixed vector results like:
<i1 true, i1 false>

alive2: https://alive2.llvm.org/ce/z/JQ_Poy

Fixes #186558

2026-03-30 14:19:05 +02:00

..

CMakeLists.txt

…

InstCombineAddSub.cpp

[InstCombine] Support disjoint or in add-sub reassociation fold (#186827)

2026-03-16 17:43:20 +00:00

InstCombineAndOrXor.cpp

Lowering ~x | (x - 1) to ~blsi(x) (#186722)

2026-03-19 20:45:56 +08:00

InstCombineAtomicRMW.cpp

[Instcombine] Write Instcombine pass to strength reduce lock xadd to lock sub (#184715)

2026-03-21 20:45:29 +00:00

InstCombineCalls.cpp

[InstCombine] Fix crash in foldReversedIntrinsicOperands for struct-return intrinsics (#186339)

2026-03-13 10:28:21 +00:00

InstCombineCasts.cpp

[InstCombine] Fold zext-add/sub-min/max-trunc to uadd.sat or usub.sat (#185259)

2026-03-27 15:14:32 +01:00

InstCombineCompares.cpp

[InstCombine] Fold cmp of select-of-constants via truth table (#186591)

2026-03-30 14:19:05 +02:00

InstCombineInternal.h

[InstCombine] Fold cmp of select-of-constants via truth table (#186591)

2026-03-30 14:19:05 +02:00

InstCombineLoadStoreAlloca.cpp

[InstCombine] RAUW for proven zero-indexed GEPs rather than cloning for a specific user (#185053)

2026-03-18 09:47:51 -05:00

InstCombineMulDivRem.cpp

[InstCombine] Fold X * ldexp(1.0, Y) -> ldexp(X, Y). (#188493)

2026-03-30 11:44:43 +01:00

InstCombineNegator.cpp

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

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

InstCombinePHI.cpp

[LLVM] remove redundant uses of dyn_cast (NFC) (#189105)

2026-03-29 18:26:54 +00:00

InstCombineSelect.cpp

InstCombine: Fold out nanless canonicalize pattern (#172998)

2026-03-25 15:09:19 +00:00

InstCombineShifts.cpp

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

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

InstCombineSimplifyDemanded.cpp

[LLVM] remove redundant uses of dyn_cast (NFC) (#189105)

2026-03-29 18:26:54 +00:00

InstCombineVectorOps.cpp

[IPO][InstCombine][Vectorize][NFCI] Drop uses of BranchInst (#186596)

2026-03-14 17:49:00 +00:00

InstructionCombining.cpp

[PatternMatch][NFC] Add m_IToFP and m_FPToI (#188040)

2026-03-23 14:10:18 +00:00