Simplify instruction removal when active lanes are unused.

paulwalker-arm · paulwalker-arm · commit b1fd235ff777 · 2025-03-13T15:43:16.000Z
diff --git a/llvm/lib/Target/AArch64/AArch64TargetTransformInfo.cpp b/llvm/lib/Target/AArch64/AArch64TargetTransformInfo.cpp
@@ -1471,13 +1471,9 @@ simplifySVEIntrinsic(InstCombiner &IC, IntrinsicInst &II,
           II, II.getOperand(IInfo.getOperandIdxInactiveLanesTakenFrom()));
 
     if (IInfo.inactiveLanesAreUnused()) {
-      if (IInfo.resultIsZeroInitialized()) {
+      if (IInfo.resultIsZeroInitialized())
         IC.replaceInstUsesWith(II, Constant::getNullValue(II.getType()));
-        // Ensure intrinsics with side effects (e.g. ld1ff) are removed.
-        return IC.eraseInstFromFunction(II);
-      }
 
-      assert(II.getType()->isVoidTy() && "Unexpected result type!");
       return IC.eraseInstFromFunction(II);
     }
   }

Original file line number	Diff line number	Diff line change
`@@ -1471,13 +1471,9 @@ simplifySVEIntrinsic(InstCombiner &IC, IntrinsicInst &II,`
`1471`	`1471`	`II, II.getOperand(IInfo.getOperandIdxInactiveLanesTakenFrom()));`
`1472`	`1472`
`1473`	`1473`	`if (IInfo.inactiveLanesAreUnused()) {`
`1474`		`- if (IInfo.resultIsZeroInitialized()) {`
	`1474`	`+ if (IInfo.resultIsZeroInitialized())`
`1475`	`1475`	`IC.replaceInstUsesWith(II, Constant::getNullValue(II.getType()));`
`1476`		`- // Ensure intrinsics with side effects (e.g. ld1ff) are removed.`
`1477`		`- return IC.eraseInstFromFunction(II);`
`1478`		`- }`
`1479`	`1476`
`1480`		`- assert(II.getType()->isVoidTy() && "Unexpected result type!");`
`1481`	`1477`	`return IC.eraseInstFromFunction(II);`
`1482`	`1478`	`}`
`1483`	`1479`	`}`