From: Eli Friedman <eli.friedman@gmail.com>
Date: Fri, 27 May 2011 22:13:20 +0000 (+0000)
Subject: Match llvm-gcc's string literals alignment by forcing alignment on string literals... 
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=b0dd6702ab5e7f53a4bdab5a3371285ad2a4b20b;p=clang

Match llvm-gcc's string literals alignment by forcing alignment on string literals to 1.  This can significantly impact the size of the string data, and as far as I know, the alignment doesn't help performance.  rdar://9078969 .



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@132223 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/CodeGen/CodeGenModule.cpp b/lib/CodeGen/CodeGenModule.cpp
index 987ebffd97..de11a29f67 100644
--- a/lib/CodeGen/CodeGenModule.cpp
+++ b/lib/CodeGen/CodeGenModule.cpp
@@ -1899,6 +1899,7 @@ static llvm::Constant *GenerateStringLiteral(llvm::StringRef str,
     new llvm::GlobalVariable(CGM.getModule(), C->getType(), constant,
                              llvm::GlobalValue::PrivateLinkage,
                              C, GlobalName);
+  GV->setAlignment(1);
   GV->setUnnamedAddr(true);
   return GV;
 }
diff --git a/test/CodeGen/string-literal.c b/test/CodeGen/string-literal.c
index 6d02b0fdaf..b5fa345bad 100644
--- a/test/CodeGen/string-literal.c
+++ b/test/CodeGen/string-literal.c
@@ -8,9 +8,9 @@ int main() {
   // CHECK: internal constant [10 x i8] c"\E1\84\A0\C8\A0\F4\82\80\B0\00", align 1
   char b[10] = "\u1120\u0220\U00102030";
 
-  // CHECK: private unnamed_addr constant [12 x i8] c"A\00\00\00B\00\00\00\00\00\00\00"
+  // CHECK: private unnamed_addr constant [12 x i8] c"A\00\00\00B\00\00\00\00\00\00\00", align 1
   void *foo = L"AB";
 
-  // CHECK: private unnamed_addr constant [12 x i8] c"4\12\00\00\0B\F0\10\00\00\00\00\00"
+  // CHECK: private unnamed_addr constant [12 x i8] c"4\12\00\00\0B\F0\10\00\00\00\00\00", align 1
   void *bar = L"\u1234\U0010F00B";
 }