diff --git a/lib/Transforms/IPO/MergeFunctions.cpp b/lib/Transforms/IPO/MergeFunctions.cpp index fa6c4ea3859..a8a85982e18 100644 --- a/lib/Transforms/IPO/MergeFunctions.cpp +++ b/lib/Transforms/IPO/MergeFunctions.cpp @@ -1559,9 +1559,16 @@ void MergeFunctions::replaceDirectCallers(Function *Old, Function *New) { CallSite CS(U->getUser()); if (CS && CS.isCallee(U)) { // Transfer the called function's attributes to the call site. Due to the - // bitcast we will 'loose' ABI changing attributes because the 'called + // bitcast we will 'lose' ABI changing attributes because the 'called // function' is no longer a Function* but the bitcast. Code that looks up // the attributes from the called function will fail. + + // FIXME: This is not actually true, at least not anymore. The callsite + // will always have the same ABI affecting attributes as the callee, + // because otherwise the original input has UB. Note that Old and New + // always have matching ABI, so no attributes need to be changed. + // Transferring other attributes may help other optimizations, but that + // should be done uniformly and not in this ad-hoc way. auto &Context = New->getContext(); auto NewFuncAttrs = New->getAttributes(); auto CallSiteAttrs = CS.getAttributes(); @@ -1656,6 +1663,7 @@ void MergeFunctions::writeThunk(Function *F, Function *G) { CallInst *CI = Builder.CreateCall(F, Args); CI->setTailCall(); CI->setCallingConv(F->getCallingConv()); + CI->setAttributes(F->getAttributes()); if (NewG->getReturnType()->isVoidTy()) { Builder.CreateRetVoid(); } else { diff --git a/test/Transforms/MergeFunc/apply_function_attributes.ll b/test/Transforms/MergeFunc/apply_function_attributes.ll index fa7f052f7ff..e9ede451820 100644 --- a/test/Transforms/MergeFunc/apply_function_attributes.ll +++ b/test/Transforms/MergeFunc/apply_function_attributes.ll @@ -38,3 +38,10 @@ define void @A(%Opaque_type* sret %a, %D2i* %b, i32* %xp, i32* %yp) { ; CHECK: tail call void bitcast (void (%Opaque_type*, %D2i*, i32*, i32*)* @A to void (%Opaque_type*, %S2i*, i32*, i32*)*)(%Opaque_type* sret %0, %S2i* %1, i32* %2, i32* %3) ; CHECK: ret void + +; Make sure we transfer the parameter attributes to the call site. +; CHECK-LABEL: define void @B(%Opaque_type* sret +; CHECK: %5 = bitcast +; CHECK: tail call void @A(%Opaque_type* sret %0, %D2i* %5, i32* %2, i32* %3) +; CHECK: ret void + diff --git a/test/Transforms/MergeFunc/inttoptr-address-space.ll b/test/Transforms/MergeFunc/inttoptr-address-space.ll index 5f672debd91..86deb2c9495 100644 --- a/test/Transforms/MergeFunc/inttoptr-address-space.ll +++ b/test/Transforms/MergeFunc/inttoptr-address-space.ll @@ -21,7 +21,7 @@ define internal i8* @func35(%.qux.2585 addrspace(1)* nocapture %this) align 2 { bb: ; CHECK-LABEL: @func35( ; CHECK: %[[V2:.+]] = bitcast %.qux.2585 addrspace(1)* %{{.*}} to %.qux.2496 addrspace(1)* -; CHECK: %[[V3:.+]] = tail call i32 @func10(%.qux.2496 addrspace(1)* %[[V2]]) +; CHECK: %[[V3:.+]] = tail call i32 @func10(%.qux.2496 addrspace(1)* nocapture %[[V2]]) ; CHECK: %{{.*}} = inttoptr i32 %[[V3]] to i8* %tmp = getelementptr inbounds %.qux.2585, %.qux.2585 addrspace(1)* %this, i32 0, i32 2 %tmp1 = load i8*, i8* addrspace(1)* %tmp, align 4 diff --git a/test/Transforms/MergeFunc/inttoptr.ll b/test/Transforms/MergeFunc/inttoptr.ll index 0abbf6239a3..05ae766a6e3 100644 --- a/test/Transforms/MergeFunc/inttoptr.ll +++ b/test/Transforms/MergeFunc/inttoptr.ll @@ -48,7 +48,7 @@ define internal i8* @func35(%.qux.2585* nocapture %this) align 2 { bb: ; CHECK-LABEL: @func35( ; CHECK: %[[V2:.+]] = bitcast %.qux.2585* %{{.*}} to %.qux.2496* -; CHECK: %[[V3:.+]] = tail call i32 @func10(%.qux.2496* %[[V2]]) +; CHECK: %[[V3:.+]] = tail call i32 @func10(%.qux.2496* nocapture %[[V2]]) ; CHECK: %{{.*}} = inttoptr i32 %[[V3]] to i8* %tmp = getelementptr inbounds %.qux.2585, %.qux.2585* %this, i32 0, i32 2 %tmp1 = load i8*, i8** %tmp, align 4