From: Saleem Abdulrasool <compnerd@compnerd.org>
Date: Sat, 9 Jul 2016 01:59:51 +0000 (+0000)
Subject: CodeGen: tweak CFString section for COFF, ELF
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=ac32f35f1795d39f9a859555ea6a50a3cd36278e;p=clang

CodeGen: tweak CFString section for COFF, ELF

Place the structure data into `cfstring`.  This both isolates the structures to
permit coalescing in the future (by the linker) as well as ensures that it
doesnt get marked as read-only data.  The structures themselves are not
read-only, only the string contents.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@274956 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/CodeGen/CodeGenModule.cpp b/lib/CodeGen/CodeGenModule.cpp
index c6e20a5f9c..55b13b4b21 100644
--- a/lib/CodeGen/CodeGenModule.cpp
+++ b/lib/CodeGen/CodeGenModule.cpp
@@ -3209,10 +3209,8 @@ CodeGenModule::GetAddrOfConstantCFString(const StringLiteral *Literal) {
   case llvm::Triple::UnknownObjectFormat:
     llvm_unreachable("unknown file format");
   case llvm::Triple::COFF:
-    GV->setSection(".rdata.cfstring");
-    break;
   case llvm::Triple::ELF:
-    GV->setSection(".rodata.cfstring");
+    GV->setSection("cfstring");
     break;
   case llvm::Triple::MachO:
     GV->setSection("__DATA,__cfstring");
diff --git a/test/CodeGen/CFStrings.c b/test/CodeGen/CFStrings.c
index d55afc25dc..17de39c6ae 100644
--- a/test/CodeGen/CFStrings.c
+++ b/test/CodeGen/CFStrings.c
@@ -21,9 +21,9 @@ const CFStringRef two = (CFStringRef)__builtin___CFStringMakeConstantString("\xe
 // CHECK-ELF: @.str = private unnamed_addr constant [4 x i8] c"one\00", align 1
 // CHECK-MACHO: @.str = private unnamed_addr constant [4 x i8] c"one\00", section "__TEXT,__cstring,cstring_literals", align 1
 
-// CHECK-COFF: @_unnamed_cfstring_ = private constant %struct.__NSConstantString_tag { i32* getelementptr inbounds ([0 x i32], [0 x i32]* @__CFConstantStringClassReference, i32 0, i32 0), i32 1992, i8* getelementptr inbounds ([4 x i8], [4 x i8]* @.str, i32 0, i32 0), i32 3 }, section ".rdata.cfstring", align {{[48]}}
-// CHECK-ELF32: @_unnamed_cfstring_ = private constant %struct.__NSConstantString_tag { i32* getelementptr inbounds ([0 x i32], [0 x i32]* @__CFConstantStringClassReference, i32 0, i32 0), i32 1992, i8* getelementptr inbounds ([4 x i8], [4 x i8]* @.str, i32 0, i32 0), i32 3 }, section ".rodata.cfstring", align 4
-// CHECK-ELF64: @_unnamed_cfstring_ = private constant %struct.__NSConstantString_tag { i32* getelementptr inbounds ([0 x i32], [0 x i32]* @__CFConstantStringClassReference, i32 0, i32 0), i32 1992, i8* getelementptr inbounds ([4 x i8], [4 x i8]* @.str, i32 0, i32 0), i64 3 }, section ".rodata.cfstring", align 8
+// CHECK-COFF: @_unnamed_cfstring_ = private constant %struct.__NSConstantString_tag { i32* getelementptr inbounds ([0 x i32], [0 x i32]* @__CFConstantStringClassReference, i32 0, i32 0), i32 1992, i8* getelementptr inbounds ([4 x i8], [4 x i8]* @.str, i32 0, i32 0), i32 3 }, section "cfstring", align {{[48]}}
+// CHECK-ELF32: @_unnamed_cfstring_ = private constant %struct.__NSConstantString_tag { i32* getelementptr inbounds ([0 x i32], [0 x i32]* @__CFConstantStringClassReference, i32 0, i32 0), i32 1992, i8* getelementptr inbounds ([4 x i8], [4 x i8]* @.str, i32 0, i32 0), i32 3 }, section "cfstring", align 4
+// CHECK-ELF64: @_unnamed_cfstring_ = private constant %struct.__NSConstantString_tag { i32* getelementptr inbounds ([0 x i32], [0 x i32]* @__CFConstantStringClassReference, i32 0, i32 0), i32 1992, i8* getelementptr inbounds ([4 x i8], [4 x i8]* @.str, i32 0, i32 0), i64 3 }, section "cfstring", align 8
 // CHECK-MACHO32: @_unnamed_cfstring_ = private constant %struct.__NSConstantString_tag { i32* getelementptr inbounds ([0 x i32], [0 x i32]* @__CFConstantStringClassReference, i32 0, i32 0), i32 1992, i8* getelementptr inbounds ([4 x i8], [4 x i8]* @.str, i32 0, i32 0), i32 3 }, section "__DATA,__cfstring", align 4
 // CHECK-MACHO64: @_unnamed_cfstring_ = private constant %struct.__NSConstantString_tag { i32* getelementptr inbounds ([0 x i32], [0 x i32]* @__CFConstantStringClassReference, i32 0, i32 0), i32 1992, i8* getelementptr inbounds ([4 x i8], [4 x i8]* @.str, i32 0, i32 0), i64 3 }, section "__DATA,__cfstring", align 8
 
@@ -31,9 +31,9 @@ const CFStringRef two = (CFStringRef)__builtin___CFStringMakeConstantString("\xe
 // CHECK-ELF: @.str.1 = private unnamed_addr constant [7 x i16] [i16 -3, i16 116, i16 -3, i16 119, i16 -3, i16 111, i16 0], align 2
 // CHECK-MACHO: @.str.1 = private unnamed_addr constant [7 x i16] [i16 -3, i16 116, i16 -3, i16 119, i16 -3, i16 111, i16 0], section "__TEXT,__ustring", align 2
 
-// CHECK-COFF: @_unnamed_cfstring_.2 = private constant %struct.__NSConstantString_tag { i32* getelementptr inbounds ([0 x i32], [0 x i32]* @__CFConstantStringClassReference, i32 0, i32 0), i32 2000, i8* bitcast ([7 x i16]* @.str.1 to i8*), i32 6 }, section ".rdata.cfstring", align {{[48]}}
-// CHECK-ELF32: @_unnamed_cfstring_.2 = private constant %struct.__NSConstantString_tag { i32* getelementptr inbounds ([0 x i32], [0 x i32]* @__CFConstantStringClassReference, i32 0, i32 0), i32 2000, i8* bitcast ([7 x i16]* @.str.1 to i8*), i32 6 }, section ".rodata.cfstring", align 4
-// CHECK-ELF64: @_unnamed_cfstring_.2 = private constant %struct.__NSConstantString_tag { i32* getelementptr inbounds ([0 x i32], [0 x i32]* @__CFConstantStringClassReference, i32 0, i32 0), i32 2000, i8* bitcast ([7 x i16]* @.str.1 to i8*), i64 6 }, section ".rodata.cfstring", align 8
+// CHECK-COFF: @_unnamed_cfstring_.2 = private constant %struct.__NSConstantString_tag { i32* getelementptr inbounds ([0 x i32], [0 x i32]* @__CFConstantStringClassReference, i32 0, i32 0), i32 2000, i8* bitcast ([7 x i16]* @.str.1 to i8*), i32 6 }, section "cfstring", align {{[48]}}
+// CHECK-ELF32: @_unnamed_cfstring_.2 = private constant %struct.__NSConstantString_tag { i32* getelementptr inbounds ([0 x i32], [0 x i32]* @__CFConstantStringClassReference, i32 0, i32 0), i32 2000, i8* bitcast ([7 x i16]* @.str.1 to i8*), i32 6 }, section "cfstring", align 4
+// CHECK-ELF64: @_unnamed_cfstring_.2 = private constant %struct.__NSConstantString_tag { i32* getelementptr inbounds ([0 x i32], [0 x i32]* @__CFConstantStringClassReference, i32 0, i32 0), i32 2000, i8* bitcast ([7 x i16]* @.str.1 to i8*), i64 6 }, section "cfstring", align 8
 // CHECK-MACHO32: @_unnamed_cfstring_.2 = private constant %struct.__NSConstantString_tag { i32* getelementptr inbounds ([0 x i32], [0 x i32]* @__CFConstantStringClassReference, i32 0, i32 0), i32 2000, i8* bitcast ([7 x i16]* @.str.1 to i8*), i32 6 }, section "__DATA,__cfstring", align 4
 // CHECK-MACHO64: @_unnamed_cfstring_.2 = private constant %struct.__NSConstantString_tag { i32* getelementptr inbounds ([0 x i32], [0 x i32]* @__CFConstantStringClassReference, i32 0, i32 0), i32 2000, i8* bitcast ([7 x i16]* @.str.1 to i8*), i64 6 }, section "__DATA,__cfstring", align 8