From 74b2743bd5b89c8184c1b3c1dd7ba49f41a5ba3f Mon Sep 17 00:00:00 2001
From: goldsteinn <35538541+goldsteinn@users.noreply.github.com>
Date: Tue, 15 Oct 2024 10:25:16 -0400
Subject: [PATCH]  [Inliner] Don't propagate access attr to byval params
 (#112256)

- **[Inliner] Add tests for bad propagationg of access attr for `byval`
param; NFC**
- **[Inliner] Don't propagate access attr to `byval` params**

We previously only handled the case where the `byval` attr was in the
callbase's param attr list. This PR also handles the case if the
`ByVal` was a param attr on the function's param attr list.

(cherry picked from commit 3c777f04f065dda5f0c80eaaef2a7f623ccc20ed)
---
 llvm/lib/Transforms/Utils/InlineFunction.cpp  |  2 +-
 .../Inline/access-attributes-prop.ll          | 20 +++++++++++++++++++
 2 files changed, 21 insertions(+), 1 deletion(-)

diff --git a/llvm/lib/Transforms/Utils/InlineFunction.cpp b/llvm/lib/Transforms/Utils/InlineFunction.cpp
index 68696789530f4a..fda1c22cc1fb7d 100644
--- a/llvm/lib/Transforms/Utils/InlineFunction.cpp
+++ b/llvm/lib/Transforms/Utils/InlineFunction.cpp
@@ -1395,7 +1395,7 @@ static void AddParamAndFnBasicAttributes(const CallBase &CB,
         if (!Arg)
           continue;
 
-        if (AL.hasParamAttr(I, Attribute::ByVal))
+        if (NewInnerCB->paramHasAttr(I, Attribute::ByVal))
           // It's unsound to propagate memory attributes to byval arguments.
           // Even if CalledFunction doesn't e.g. write to the argument,
           // the call to NewInnerCB may write to its by-value copy.
diff --git a/llvm/test/Transforms/Inline/access-attributes-prop.ll b/llvm/test/Transforms/Inline/access-attributes-prop.ll
index 2c55f5f3b1f6ca..5051c92345ec75 100644
--- a/llvm/test/Transforms/Inline/access-attributes-prop.ll
+++ b/llvm/test/Transforms/Inline/access-attributes-prop.ll
@@ -580,3 +580,23 @@ define ptr @callee_bad_param_prop(ptr readonly %x) {
   %r = tail call ptr @llvm.ptrmask(ptr %x, i64 -1)
   ret ptr %r
 }
+
+define dso_local void @foo_byval_readonly2(ptr readonly %p) {
+; CHECK-LABEL: define {{[^@]+}}@foo_byval_readonly2
+; CHECK-SAME: (ptr readonly [[P:%.*]]) {
+; CHECK-NEXT:    call void @bar4(ptr [[P]])
+; CHECK-NEXT:    ret void
+;
+  call void @bar4(ptr %p)
+  ret void
+}
+
+define void @prop_byval_readonly2(ptr %p) {
+; CHECK-LABEL: define {{[^@]+}}@prop_byval_readonly2
+; CHECK-SAME: (ptr [[P:%.*]]) {
+; CHECK-NEXT:    call void @bar4(ptr [[P]])
+; CHECK-NEXT:    ret void
+;
+  call void @foo_byval_readonly2(ptr %p)
+  ret void
+}