[mte] fix runOnFunction return value falsely suggesting function was modified.

fmayer · fmayer · commit 3918dd6b8acf · 2022-02-04T10:34:14.000-08:00
If NumInterestingAllocas == 0 we do not add any instrumentation or padding in the previous loop. Reviewed By: eugenis Differential Revision: https://reviews.llvm.org/D118961
diff --git a/llvm/lib/Target/AArch64/AArch64StackTagging.cpp b/llvm/lib/Target/AArch64/AArch64StackTagging.cpp
@@ -605,7 +605,7 @@ bool AArch64StackTagging::runOnFunction(Function &Fn) {
   }
 
   if (NumInterestingAllocas == 0)
-    return true;
+    return false;
 
   std::unique_ptr<DominatorTree> DeleteDT;
   DominatorTree *DT = nullptr;

Original file line number	Diff line number	Diff line change
`@@ -605,7 +605,7 @@ bool AArch64StackTagging::runOnFunction(Function &Fn) {`
`605`	`605`	`}`
`606`	`606`
`607`	`607`	`if (NumInterestingAllocas == 0)`
`608`		`- return true;`
	`608`	`+ return false;`
`609`	`609`
`610`	`610`	`std::unique_ptr<DominatorTree> DeleteDT;`
`611`	`611`	`DominatorTree *DT = nullptr;`