From 1bd59c97fb6f0dea34daf63f231aca3edc6c3206 Mon Sep 17 00:00:00 2001
From: David Majnemer <david.majnemer@gmail.com>
Date: Sun, 11 Jan 2015 09:09:01 +0000
Subject: [PATCH] CodeGen: Simplify consecutive '&' modifiers

LLVM the consecutive '&' modifiers are redundant, skip them.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@225601 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/CodeGen/CGStmt.cpp | 5 +++++
 test/CodeGen/asm.c     | 7 +++++++
 2 files changed, 12 insertions(+)

diff --git a/lib/CodeGen/CGStmt.cpp b/lib/CodeGen/CGStmt.cpp
index a003e8ab9e..d910f2fb96 100644
--- a/lib/CodeGen/CGStmt.cpp
+++ b/lib/CodeGen/CGStmt.cpp
@@ -1659,6 +1659,11 @@ SimplifyConstraint(const char *Constraint, const TargetInfo &Target,
       while (Constraint[1] && Constraint[1] != ',')
         Constraint++;
       break;
+    case '&':
+      Result += '&';
+      while (Constraint[1] && Constraint[1] == '&')
+        Constraint++;
+      break;
     case ',':
       Result += "|";
       break;
diff --git a/test/CodeGen/asm.c b/test/CodeGen/asm.c
index 5dbc01b121..c64f83f787 100644
--- a/test/CodeGen/asm.c
+++ b/test/CodeGen/asm.c
@@ -248,3 +248,10 @@ void t29(void) {
   // CHECK: @t29
   // CHECK: call void asm sideeffect "movl %eax, $0", "*m,~{dirflag},~{fpsr},~{flags}"([1 x i32]* @t29_var)
 }
+
+void t30(int len) {
+  __asm__ volatile(""
+                   : "+&&rm"(len));
+  // CHECK: @t30
+  // CHECK: call void asm sideeffect "", "=*&rm,0,~{dirflag},~{fpsr},~{flags}"
+}
-- 
2.50.1