[SimplifyLibCalls] Retain attributes added by Builder.CreateMem*

This currently does not make much of a difference (only one tests is
affected), but it is helpful e.g. for the out-of-tree CHERI target where
Builder.CreateMemCpy() can add attributes other than parameter alignment.

Reviewed By: nikic

Differential Revision: https://reviews.llvm.org/D135075

diff --git a/llvm/lib/Transforms/Utils/SimplifyLibCalls.cpp b/llvm/lib/Transforms/Utils/SimplifyLibCalls.cpp
index 0303831..be0912b 100644 (file)
--- a/llvm/lib/Transforms/Utils/SimplifyLibCalls.cpp
+++ b/llvm/lib/Transforms/Utils/SimplifyLibCalls.cpp
@@ -289,7 +289,8 @@ static Value *copyFlags(const CallInst &Old, Value *New) {
 }
 
 static Value *mergeAttributesAndFlags(CallInst *NewCI, const CallInst &Old) {
-  NewCI->setAttributes(Old.getAttributes());
+  NewCI->setAttributes(AttributeList::get(
+      NewCI->getContext(), {NewCI->getAttributes(), Old.getAttributes()}));
   NewCI->removeRetAttrs(AttributeFuncs::typeIncompatible(NewCI->getType()));
   return copyFlags(Old, NewCI);
 }

diff --git a/llvm/test/Transforms/CodeGenPrepare/X86/memset_chk-simplify-nobuiltin.ll b/llvm/test/Transforms/CodeGenPrepare/X86/memset_chk-simplify-nobuiltin.ll
index cd982f6..3524578 100644 (file)
--- a/llvm/test/Transforms/CodeGenPrepare/X86/memset_chk-simplify-nobuiltin.ll
+++ b/llvm/test/Transforms/CodeGenPrepare/X86/memset_chk-simplify-nobuiltin.ll
@@ -11,7 +11,7 @@ target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128"
 
 define void @test_nobuiltin(i8* %dst, i64 %len) {
 ; CHECK-LABEL: @test_nobuiltin(
-; CHECK-NEXT:    call void @llvm.memset.p0i8.i64(i8* [[DST:%.*]], i8 0, i64 [[LEN:%.*]], i1 false) #1
+; CHECK-NEXT:    call void @llvm.memset.p0i8.i64(i8* align 1 [[DST:%.*]], i8 0, i64 [[LEN:%.*]], i1 false)
 ; CHECK-NEXT:    ret void
 ;
   call i8* @__memset_chk(i8* %dst, i32 0, i64 %len, i64 -1) nobuiltin