[CallPromotion] Check for inalloca/byval mismatch

[aeubanks]

Summary

Previously we would allow promotion even if the byval/inalloca
attributes on the call and the callee didn't match.

It's ok if the byval/inalloca types aren't the same. For example, LTO
importing may rename types.

Fixes PR51397.

[aeubanks]

use hasParamAttribute()

[rnk]

lgtm

llvm/lib/Transforms/Utils/CallPromotionUtils.cpp

for (; I < NumParams; ++I) {
     Type *ActualTy = CB.getArgOperand(I)->getType();
     if (FormalTy == ActualTy)
       continue;
     if (!CastInst::isBitOrNoopPointerCastable(ActualTy, FormalTy, DL)) {
       if (FailureReason)
         *FailureReason = "Argument type mismatch";
       return false;
     }
+    // Make sure that the callee and call agree on byval/inalloca. The types do
+    // not have to match.
+
+    if (Callee->hasParamAttribute(I, Attribute::ByVal) !=
+        CB.getAttributes().hasParamAttr(I, Attribute::ByVal)) {
+      if (FailureReason)
+        *FailureReason = "byval mismatch";
+      return false;
+    }
+    if (Callee->hasParamAttribute(I, Attribute::InAlloca) !=
+        CB.getAttributes().hasParamAttr(I, Attribute::InAlloca)) {
+      if (FailureReason)
+        *FailureReason = "inalloca mismatch";
+      return false;
+    }
   }
   for (; I < NumArgs; I++) {
     // Vararg functions can have more arguments than parameters.
     assert(Callee->isVarArg());
     if (CB.paramHasAttr(I, Attribute::StructRet)) {
       if (FailureReason)
         *FailureReason = "SRet arg to vararg function";
       return false;
for (unsigned ArgNo = 0; ArgNo < CalleeParamNum; ++ArgNo) {
     if (FormalTy != ActualTy) {
       auto *Cast = CastInst::CreateBitOrPointerCast(Arg, FormalTy, "", &CB);
       CB.setArgOperand(ArgNo, Cast);
 
       // Remove any incompatible attributes for the argument.
       AttrBuilder ArgAttrs(CallerPAL.getParamAttrs(ArgNo));
       ArgAttrs.remove(AttributeFuncs::typeIncompatible(FormalTy));
 
-      // If byval is used, this must be a pointer type, and the byval type must
-      // match the element type. Update it if present.
+      // We may have a different byval/inalloca type.
       if (ArgAttrs.getByValType())
         ArgAttrs.addByValAttr(Callee->getParamByValType(ArgNo));
+      if (ArgAttrs.getInAllocaType())
+        ArgAttrs.addInAllocaAttr(Callee->getParamInAllocaType(ArgNo));
 
       NewArgAttrs.push_back(AttributeSet::get(Ctx, ArgAttrs));
       AttributeChanged = true;
     } else
       NewArgAttrs.push_back(CallerPAL.getParamAttrs(ArgNo));
   }
 
   // If the return type of the call site doesn't match that of the callee, cast

llvm/test/Transforms/PGOProfile/mismatched-byval.ll

+; RUN: opt -passes=pgo-icall-prom -profile-summary-hot-count=10 -S < %s -pass-remarks-output=- | FileCheck %s
+
+; CHECK: byval mismatch
+
+define void @a(i8* %0) !prof !0 {
+  ret void
+}
+
+define void @b(void (i64*)** %v, i64* %p) !prof !1 {
+; CHECK-LABEL: @b
+; CHECK-NEXT: load
+; CHECK-NEXT: call void {{.*}}(i64* byval(i64)
+; CHECK-NEXT: ret void
+;
+  %a = load void (i64*)*, void (i64*)** %v
+  call void %a(i64* byval(i64) %p), !prof !2
+  ret void
+}
+
+!0 = !{!"function_entry_count", i64 36}
+!1 = !{!"function_entry_count", i64 1}
+!2 = !{!"VP", i32 0, i64 18, i64 12157170054180749580, i64 18}

llvm/test/Transforms/PGOProfile/mismatched-inalloca.ll

+; RUN: opt -passes=pgo-icall-prom -profile-summary-hot-count=10 -S < %s -pass-remarks-output=- | FileCheck %s
+
+; CHECK: inalloca mismatch
+
+define void @a(i8* %0) !prof !0 {
+  ret void
+}
+
+define void @b(void (i64*)** %v, i64* %p) !prof !1 {
+; CHECK-LABEL: @b
+; CHECK-NEXT: load
+; CHECK-NEXT: call void {{.*}}(i64* inalloca(i64)
+; CHECK-NEXT: ret void
+  %a = load void (i64*)*, void (i64*)** %v
+  call void %a(i64* inalloca(i64) %p), !prof !2
+  ret void
+}
+
+!0 = !{!"function_entry_count", i64 36}
+!1 = !{!"function_entry_count", i64 1}
+!2 = !{!"VP", i32 0, i64 18, i64 12157170054180749580, i64 18}