From: John McCall <rjmccall@apple.com>
Date: Tue, 29 Sep 2015 04:37:40 +0000 (+0000)
Subject: Honor the casted-to alignment of an explicit cast even when
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=6963521379311a80c849bf4b81fcfe4604483f0f;p=clang

Honor the casted-to alignment of an explicit cast even when
Sema thinks the cast is a no-op, as it does when (e.g.) the
only thing that changes is an alignment attribute.

Fixed PR24944.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@248775 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/CodeGen/CGExpr.cpp b/lib/CodeGen/CGExpr.cpp
index c38dbdd7d3..ece83371db 100644
--- a/lib/CodeGen/CGExpr.cpp
+++ b/lib/CodeGen/CGExpr.cpp
@@ -814,7 +814,6 @@ Address CodeGenFunction::EmitPointerWithAlignment(const Expr *E,
         // If this is an explicit bitcast, and the source l-value is
         // opaque, honor the alignment of the casted-to type.
         if (isa<ExplicitCastExpr>(CE) &&
-            CE->getCastKind() == CK_BitCast &&
             InnerSource != AlignmentSource::Decl) {
           Addr = Address(Addr.getPointer(),
                          getNaturalPointeeTypeAlignment(E->getType(), Source));
diff --git a/test/CodeGen/alignment.c b/test/CodeGen/alignment.c
index 0a598010c8..c9f58136e3 100644
--- a/test/CodeGen/alignment.c
+++ b/test/CodeGen/alignment.c
@@ -59,3 +59,11 @@ void test4(float4align64 *p) {
 // CHECK: @test4(
 // CHECK: store <4 x float> {{.*}}, <4 x float>* {{.*}}, align 64
 
+// PR24944 - Typedef alignment not honored on no-op cast.
+typedef float __attribute__((vector_size(16), aligned(16))) float4align16;
+typedef float __attribute__((vector_size(16), aligned(2))) float4align2;
+void test6(float4align64 *p) {
+    float4align64 vec = *(float4align2*) p;
+}
+// CHECK-LABEL: @test6
+// CHECK:       load <4 x float>, <4 x float>* {{.*}}, align 2