# Based on https://github.com/ispc/ispc/blob/main/llvm_patches/12_0_disable-A-B-A-B-and-BSWAP-in-InstCombine.patch

diff --git a/llvm/lib/Transforms/InstCombine/InstCombineAddSub.cpp b/llvm/lib/Transforms/InstCombine/InstCombineAddSub.cpp
index d01a021bf3f4..bccce825a03d 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombineAddSub.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstCombineAddSub.cpp
@@ -15,6 +15,7 @@
 #include "llvm/ADT/APInt.h"
 #include "llvm/ADT/STLExtras.h"
 #include "llvm/ADT/SmallVector.h"
+#include "llvm/ADT/Triple.h"
 #include "llvm/Analysis/InstructionSimplify.h"
 #include "llvm/Analysis/ValueTracking.h"
 #include "llvm/IR/Constant.h"
@@ -1369,9 +1370,12 @@ Instruction *InstCombinerImpl::visitAdd(BinaryOperator &I) {
     }
   }
 
-  // A+B --> A|B iff A and B have no bits set in common.
-  if (haveNoCommonBitsSet(LHS, RHS, DL, &AC, &I, &DT))
-    return BinaryOperator::CreateOr(LHS, RHS);
+  // Disable this transformation for ISPC SPIR-V
+  if (!Triple(I.getModule()->getTargetTriple()).isSPIR()) {
+    // A+B --> A|B iff A and B have no bits set in common.
+    if (haveNoCommonBitsSet(LHS, RHS, DL, &AC, &I, &DT))
+      return BinaryOperator::CreateOr(LHS, RHS);
+  }
 
   // add (select X 0 (sub n A)) A  -->  select X A n
   {
diff --git a/llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp b/llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp
index 120852c44474..8de55311ce3e 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp
@@ -2671,9 +2671,12 @@ Instruction *InstCombinerImpl::visitOr(BinaryOperator &I) {
   if (Instruction *FoldedLogic = foldBinOpIntoSelectOrPhi(I))
     return FoldedLogic;
 
-  if (Instruction *BitOp = matchBSwapOrBitReverse(I, /*MatchBSwaps*/ true,
-                                                  /*MatchBitReversals*/ true))
-    return BitOp;
+  // Disable this transformation for ISPC SPIR-V
+  if (!Triple(I.getModule()->getTargetTriple()).isSPIR()) {
+    if (Instruction *BitOp = matchBSwapOrBitReverse(I, /*MatchBSwaps*/ true,
+                                                    /*MatchBitReversals*/ true))
+      return BitOp;
+  }
 
   if (Instruction *Funnel = matchFunnelShift(I, *this))
     return Funnel;