llvm13/trunk/disable-A-B-A-B-and-BSWAP-in-InstCombine.patch

   1 # This patch is needed for ISPC for Xe only
   2
   3 # 1. Transformation of add to or is not safe for VC backend.
   4 # 2. bswap intrinsics is not supported in VC backend yet.
   5 diff --git a/llvm/lib/Transforms/InstCombine/InstCombineAddSub.cpp b/llvm/lib/Transforms/InstCombine/InstCombineAddSub.cpp
   6 index d01a021bf3f4..bccce825a03d 100644
   7 --- a/llvm/lib/Transforms/InstCombine/InstCombineAddSub.cpp
   8 +++ b/llvm/lib/Transforms/InstCombine/InstCombineAddSub.cpp
   9 @@ -15,6 +15,7 @@
  10  #include "llvm/ADT/APInt.h"
  11  #include "llvm/ADT/STLExtras.h"
  12  #include "llvm/ADT/SmallVector.h"
  13 +#include "llvm/ADT/Triple.h"
  14  #include "llvm/Analysis/InstructionSimplify.h"
  15  #include "llvm/Analysis/ValueTracking.h"
  16  #include "llvm/IR/Constant.h"
  17 @@ -1369,9 +1370,12 @@ Instruction *InstCombinerImpl::visitAdd(BinaryOperator &I) {
  18      }
  19    }
  20
  21 -  // A+B --> A|B iff A and B have no bits set in common.
  22 -  if (haveNoCommonBitsSet(LHS, RHS, DL, &AC, &I, &DT))
  23 -    return BinaryOperator::CreateOr(LHS, RHS);
  24 +  // Disable this transformation for ISPC SPIR-V
  25 +  if (!Triple(I.getModule()->getTargetTriple()).isSPIR()) {
  26 +    // A+B --> A|B iff A and B have no bits set in common.
  27 +    if (haveNoCommonBitsSet(LHS, RHS, DL, &AC, &I, &DT))
  28 +      return BinaryOperator::CreateOr(LHS, RHS);
  29 +  }
  30
  31    // add (select X 0 (sub n A)) A  -->  select X A n
  32    {
  33 diff --git a/llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp b/llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp
  34 index 120852c44474..8de55311ce3e 100644
  35 --- a/llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp
  36 +++ b/llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp
  37 @@ -2671,9 +2671,12 @@ Instruction *InstCombinerImpl::visitOr(BinaryOperator &I) {
  38    if (Instruction *FoldedLogic = foldBinOpIntoSelectOrPhi(I))
  39      return FoldedLogic;
  40
  41 -  if (Instruction *BitOp = matchBSwapOrBitReverse(I, /*MatchBSwaps*/ true,
  42 -                                                  /*MatchBitReversals*/ true))
  43 -    return BitOp;
  44 +  // Disable this transformation for ISPC SPIR-V
  45 +  if (!Triple(I.getModule()->getTargetTriple()).isSPIR()) {
  46 +    if (Instruction *BitOp = matchBSwapOrBitReverse(I, /*MatchBSwaps*/ true,
  47 +                                                    /*MatchBitReversals*/ true))
  48 +      return BitOp;
  49 +  }
  50
  51    if (Instruction *Funnel = matchFunnelShift(I, *this))
  52      return Funnel;