Fix CodeGenPrepare::stripInvariantGroupMetadata

`dropUnknownNonDebugMetadata` takes a list of "known" metadata IDs.  The
only reason it worked at all is that `getMetadataID` returns something
unrelated -- it returns the subclass ID of the receiver (which is used
in `dyn_cast` etc.).  That does not numerically match
`LLVMContext::MD_invariant_group` and ends up dropping `invariant_group`
along with every other metadata that does not numerically match
`LLVMContext::MD_invariant_group`.

llvm-svn: 289973

diff --git a/llvm/lib/CodeGen/CodeGenPrepare.cpp b/llvm/lib/CodeGen/CodeGenPrepare.cpp
index 0ae57ce..bc333b9 100644 (file)
--- a/llvm/lib/CodeGen/CodeGenPrepare.cpp
+++ b/llvm/lib/CodeGen/CodeGenPrepare.cpp
@@ -5735,6 +5735,5 @@ bool CodeGenPrepare::splitBranchCondition(Function &F) {
 }
 
 void CodeGenPrepare::stripInvariantGroupMetadata(Instruction &I) {
-  if (auto *InvariantMD = I.getMetadata(LLVMContext::MD_invariant_group))
-    I.dropUnknownNonDebugMetadata(InvariantMD->getMetadataID());
+  I.setMetadata(LLVMContext::MD_invariant_group, nullptr);
 }

diff --git a/llvm/test/Transforms/CodeGenPrepare/invariant.group.ll b/llvm/test/Transforms/CodeGenPrepare/invariant.group.ll
index e8f1e42..bde04a5 100644 (file)
--- a/llvm/test/Transforms/CodeGenPrepare/invariant.group.ll
+++ b/llvm/test/Transforms/CodeGenPrepare/invariant.group.ll
@@ -7,8 +7,8 @@ define void @foo() {
 enter:
   ; CHECK-NOT: !invariant.group
   ; CHECK-NOT: @llvm.invariant.group.barrier(
-  ; CHECK: %val = load i8, i8* @tmp
-  %val = load i8, i8* @tmp, !invariant.group !0
+  ; CHECK: %val = load i8, i8* @tmp, !tbaa
+  %val = load i8, i8* @tmp, !invariant.group !0, !tbaa !{!1, !1, i64 0}
   %ptr = call i8* @llvm.invariant.group.barrier(i8* @tmp)
   
   ; CHECK: store i8 42, i8* @tmp
@@ -20,4 +20,5 @@ enter:
 
 declare i8* @llvm.invariant.group.barrier(i8*)
 
-!0 = !{!"something"}
\ No newline at end of file
+!0 = !{!"something"}
+!1 = !{!"x", !0}