[llvm] 32efff5 - [VPlan] Mark load VPWidenMemoryInstruction as not having side-effects.

[Florian Hahn via llvm-commits]

Author: Florian Hahn
Date: 2023-02-07T22:02:50Z
New Revision: 32efff591abb159ca18d6c8c974d3ca45d444864

URL: https://github.com/llvm/llvm-project/commit/32efff591abb159ca18d6c8c974d3ca45d444864
DIFF: https://github.com/llvm/llvm-project/commit/32efff591abb159ca18d6c8c974d3ca45d444864.diff

LOG: [VPlan] Mark load VPWidenMemoryInstruction as not having side-effects.

Also add an assert using the underlying instruction to catch any
potential violations.

Added: 
    

Modified: 
    llvm/lib/Transforms/Vectorize/VPlanRecipes.cpp
    llvm/unittests/Transforms/Vectorize/VPlanTest.cpp

Removed: 
    


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diff  --git a/llvm/lib/Transforms/Vectorize/VPlanRecipes.cpp b/llvm/lib/Transforms/Vectorize/VPlanRecipes.cpp
index 34981111c85e5..ff0b1df57ce4a 100644
--- a/llvm/lib/Transforms/Vectorize/VPlanRecipes.cpp
+++ b/llvm/lib/Transforms/Vectorize/VPlanRecipes.cpp
@@ -127,6 +127,13 @@ bool VPRecipeBase::mayHaveSideEffects() const {
            "underlying instruction has side-effects");
     return false;
   }
+  case VPWidenMemoryInstructionSC:
+    assert(cast<VPWidenMemoryInstructionRecipe>(this)
+                   ->getIngredient()
+                   .mayHaveSideEffects() == mayWriteToMemory() &&
+           "mayHaveSideffects result for ingredient 
diff ers from this "
+           "implementation");
+    return mayWriteToMemory();
   case VPReplicateSC: {
     auto *R = cast<VPReplicateRecipe>(this);
     return R->getUnderlyingInstr()->mayHaveSideEffects();

diff  --git a/llvm/unittests/Transforms/Vectorize/VPlanTest.cpp b/llvm/unittests/Transforms/Vectorize/VPlanTest.cpp
index a8797994bc93b..ff7ee53bfbcf0 100644
--- a/llvm/unittests/Transforms/Vectorize/VPlanTest.cpp
+++ b/llvm/unittests/Transforms/Vectorize/VPlanTest.cpp
@@ -1100,7 +1100,7 @@ TEST(VPRecipeTest, MayHaveSideEffectsAndMayReadWriteMemory) {
     VPValue Addr;
     VPValue Mask;
     VPWidenMemoryInstructionRecipe Recipe(*Load, &Addr, &Mask, true, false);
-    EXPECT_TRUE(Recipe.mayHaveSideEffects());
+    EXPECT_FALSE(Recipe.mayHaveSideEffects());
     EXPECT_TRUE(Recipe.mayReadFromMemory());
     EXPECT_FALSE(Recipe.mayWriteToMemory());
     EXPECT_TRUE(Recipe.mayReadOrWriteMemory());