[AlwaysInliner] Call mergeAttributesForInlining after inlining

[Carrot]

Summary

Like inlineCallIfPossible and InlinerPass, after inlining mergeAttributesForInlining should be called to merge callee's attributes to caller. But it is not called in AlwaysInliner, causes caller's attributes inconsistent with inlined code.

Attached test case demonstrates that attribute "min-legal-vector-width"="512" is not merged into caller without this patch, and it causes failure in SelectionDAG when lowering the inlined AVX512 intrinsic.

[echristo]

I'd just seen that too. Thanks!

-eric

[aeubanks]

mtrofin proposed reusing much of InlinerPass for AlwaysInlinerPass in https://reviews.llvm.org/D86988 which would probably make this sort of bug much less likely.

[echristo]

Also probably a good idea :)

llvm/lib/Transforms/IPO/AlwaysInliner.cpp

if (!F.isDeclaration() && F.hasFnAttribute(Attribute::AlwaysInline) &&
             /*cg=*/nullptr, GetAssumptionCache, &PSI,
             &FAM.getResult<BlockFrequencyAnalysis>(*(CB->getCaller())),
             &FAM.getResult<BlockFrequencyAnalysis>(F));
 
         InlineResult Res = InlineFunction(
             *CB, IFI, &FAM.getResult<AAManager>(F), InsertLifetime);
         assert(Res.isSuccess() && "unexpected failure to inline");
         (void)Res;
+
+        // Merge the attributes based on the inlining.
+        AttributeFuncs::mergeAttributesForInlining(*Caller, F);
+
         Changed = true;
       }
 
       // Remember to try and delete this function afterward. This both avoids
       // re-walking the rest of the module and avoids dealing with any iterator
       // invalidation issues while deleting functions.
       InlinedFunctions.push_back(&F);
     }

llvm/test/Transforms/Inline/always-inline-attr.ll

+; RUN: opt -passes=always-inline -S < %s | FileCheck %s
+
+
+target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-grtev4-linux-gnu"
+
+; After AlwaysInline the callee's attributes should be merged into caller's attibutes.
+
+; CHECK:  define dso_local <2 x i64> @foo(<8 x i64>* byval(<8 x i64>) align 64 %0) #0
+; CHECK:  attributes #0 = { uwtable mustprogress "disable-tail-calls"="false" "frame-pointer"="none" "less-precise-fpmad"="false" "min-legal-vector-width"="512"
+
+; Function Attrs: uwtable mustprogress
+define dso_local <2 x i64> @foo(<8 x i64>* byval(<8 x i64>) align 64 %0) #0 {
+entry:
+  %kBias.addr = alloca <8 x i64>, align 64
+  %indirect-arg-temp = alloca <8 x i64>, align 64
+  %kBias = load <8 x i64>, <8 x i64>* %0, align 64, !tbaa !2
+  store <8 x i64> %kBias, <8 x i64>* %kBias.addr, align 64, !tbaa !2
+  %1 = load <8 x i64>, <8 x i64>* %kBias.addr, align 64, !tbaa !2
+  store <8 x i64> %1, <8 x i64>* %indirect-arg-temp, align 64, !tbaa !2
+  %call = call <2 x i64> @bar(<8 x i64>* byval(<8 x i64>) align 64 %indirect-arg-temp)
+  ret <2 x i64> %call
+}
+
+; Function Attrs: alwaysinline nounwind uwtable mustprogress
+define internal <2 x i64> @bar(<8 x i64>* byval(<8 x i64>) align 64 %0) #1 {
+entry:
+  %__A.addr = alloca <8 x i64>, align 64
+  %__A = load <8 x i64>, <8 x i64>* %0, align 64, !tbaa !2
+  store <8 x i64> %__A, <8 x i64>* %__A.addr, align 64, !tbaa !2
+  %1 = load <8 x i64>, <8 x i64>* %__A.addr, align 64, !tbaa !2
+  %2 = bitcast <8 x i64> %1 to <16 x i32>
+  %3 = call <16 x i8> @llvm.x86.avx512.mask.pmovs.db.512(<16 x i32> %2, <16 x i8> zeroinitializer, i16 -1)
+  %4 = bitcast <16 x i8> %3 to <2 x i64>
+  ret <2 x i64> %4
+}
+
+; Function Attrs: nounwind readnone
+declare <16 x i8> @llvm.x86.avx512.mask.pmovs.db.512(<16 x i32>, <16 x i8>, i16) #2
+
+attributes #0 = { uwtable mustprogress "disable-tail-calls"="false" "frame-pointer"="none" "less-precise-fpmad"="false" "min-legal-vector-width"="128" "no-infs-fp-math"="false" "no-jump-tables"="false" "no-nans-fp-math"="false" "no-signed-zeros-fp-math"="false" "no-trapping-math"="true" "prefer-vector-width"="128" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+aes,+avx,+avx2,+avx512bw,+avx512dq,+avx512f,+avx512vl,+bmi2,+cx16,+cx8,+f16c,+fma,+fxsr,+mmx,+pclmul,+popcnt,+sse,+sse2,+sse3,+sse4.1,+sse4.2,+ssse3,+x87,+xsave" "tune-cpu"="generic" "unsafe-fp-math"="false" "use-soft-float"="false" }
+attributes #1 = { alwaysinline nounwind uwtable mustprogress "disable-tail-calls"="false" "frame-pointer"="none" "less-precise-fpmad"="false" "min-legal-vector-width"="512" "no-infs-fp-math"="false" "no-jump-tables"="false" "no-nans-fp-math"="false" "no-signed-zeros-fp-math"="false" "no-trapping-math"="true" "prefer-vector-width"="128" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+aes,+avx,+avx2,+avx512f,+cx16,+cx8,+f16c,+fma,+fxsr,+mmx,+pclmul,+popcnt,+sse,+sse2,+sse3,+sse4.1,+sse4.2,+ssse3,+x87,+xsave" "tune-cpu"="generic" "unsafe-fp-math"="false" "use-soft-float"="false" }
+attributes #2 = { nounwind readnone }
+
+
+!2 = !{!3, !3, i64 0}
+!3 = !{!"omnipotent char", !4, i64 0}
+!4 = !{!"Simple C++ TBAA"}