From: John McCall <rjmccall@apple.com>
Date: Thu, 9 Nov 2017 09:32:32 +0000 (+0000)
Subject: Fix a bug with the use of __builtin_bzero in a conditional expression.
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=b0146f934b6fe813689ec0058323e52bc12dec23;p=clang

Fix a bug with the use of __builtin_bzero in a conditional expression.

Patch by Bharathi Seshadri!

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@317776 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/CodeGen/CGBuiltin.cpp b/lib/CodeGen/CGBuiltin.cpp
index 369240f316..2d1b4f40dc 100644
--- a/lib/CodeGen/CGBuiltin.cpp
+++ b/lib/CodeGen/CGBuiltin.cpp
@@ -1431,7 +1431,7 @@ RValue CodeGenFunction::EmitBuiltinExpr(const FunctionDecl *FD,
     EmitNonNullArgCheck(RValue::get(Dest.getPointer()), E->getArg(0)->getType(),
                         E->getArg(0)->getExprLoc(), FD, 0);
     Builder.CreateMemSet(Dest, Builder.getInt8(0), SizeVal, false);
-    return RValue::get(Dest.getPointer());
+    return RValue::get(nullptr);
   }
   case Builtin::BImemcpy:
   case Builtin::BI__builtin_memcpy: {
diff --git a/test/CodeGen/builtins.c b/test/CodeGen/builtins.c
index 86bee451ec..0207bb6c9f 100644
--- a/test/CodeGen/builtins.c
+++ b/test/CodeGen/builtins.c
@@ -176,6 +176,19 @@ void bar() {
 }
 // CHECK: }
 
+// CHECK-LABEL: define void @test_conditional_bzero
+void test_conditional_bzero() {
+  char dst[20];
+  int _sz = 20, len = 20;
+  return (_sz
+          ? ((_sz >= len)
+              ? __builtin_bzero(dst, len)
+              : foo())
+          : __builtin_bzero(dst, len));
+  // CHECK: call void @llvm.memset
+  // CHECK: call void @llvm.memset
+  // CHECK-NOT: phi
+}
 
 // CHECK-LABEL: define void @test_float_builtins
 void test_float_builtins(float F, double D, long double LD) {