Always use the string pool, even when it makes the .o larger. This may help

tools that read the debug info in the .o files by making the DIE sizes more
consistent.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@143186 91177308-0d34-0410-b5e6-96231b3b80d8

11 files changed, 39 insertions, 102 deletions

diff --git a/lib/CodeGen/AsmPrinter/DIE.cpp b/lib/CodeGen/AsmPrinter/DIE.cpp
index fad3d0d..a2dc873 100644
--- a/lib/CodeGen/AsmPrinter/DIE.cpp
+++ b/lib/CodeGen/AsmPrinter/DIE.cpp
@@ -236,24 +236,6 @@ void DIEInteger::print(raw_ostream &O) {
 #endif
 
 //===----------------------------------------------------------------------===//
-// DIEString Implementation
-//===----------------------------------------------------------------------===//
-
-/// EmitValue - Emit string value.
-///
-void DIEString::EmitValue(AsmPrinter *AP, unsigned Form) const {
-  AP->OutStreamer.EmitBytes(Str, /*addrspace*/0);
-  // Emit nul terminator.
-  AP->OutStreamer.EmitIntValue(0, 1, /*addrspace*/0);
-}
-
-#ifndef NDEBUG
-void DIEString::print(raw_ostream &O) {
-  O << "Str: \"" << Str << "\"";
-}
-#endif
-
-//===----------------------------------------------------------------------===//
 // DIELabel Implementation
 //===----------------------------------------------------------------------===//
 
diff --git a/lib/CodeGen/AsmPrinter/DIE.h b/lib/CodeGen/AsmPrinter/DIE.h
index 12448af..265446c 100644
--- a/lib/CodeGen/AsmPrinter/DIE.h
+++ b/lib/CodeGen/AsmPrinter/DIE.h
@@ -275,33 +275,6 @@ namespace llvm {
   };
 
   //===--------------------------------------------------------------------===//
-  /// DIEString - A string value DIE. This DIE keeps string reference only.
-  ///
-  class DIEString : public DIEValue {
-    const StringRef Str;
-  public:
-    explicit DIEString(const StringRef S) : DIEValue(isString), Str(S) {}
-
-    /// EmitValue - Emit string value.
-    ///
-    virtual void EmitValue(AsmPrinter *AP, unsigned Form) const;
-
-    /// SizeOf - Determine size of string value in bytes.
-    ///
-    virtual unsigned SizeOf(AsmPrinter *AP, unsigned /*Form*/) const {
-      return Str.size() + sizeof(char); // sizeof('\0');
-    }
-
-    // Implement isa/cast/dyncast.
-    static bool classof(const DIEString *) { return true; }
-    static bool classof(const DIEValue *S) { return S->getType() == isString; }
-
-#ifndef NDEBUG
-    virtual void print(raw_ostream &O);
-#endif
-  };
-
-  //===--------------------------------------------------------------------===//
   /// DIELabel - A label expression DIE.
   //
   class DIELabel : public DIEValue {
diff --git a/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp b/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp
index a6a004d..f9f1642 100644
--- a/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp
+++ b/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp
@@ -67,23 +67,19 @@ void CompileUnit::addSInt(DIE *Die, unsigned Attribute,
   Die->addValue(Attribute, Form, Value);
 }
 
-/// addString - Add a string attribute data and value. DIEString only
-/// keeps string reference.
+/// addString - Add a string attribute data and value. We always emit a
+/// reference to the string pool instead of immediate strings so that DIEs have
+/// more predictable sizes.
 void CompileUnit::addString(DIE *Die, unsigned Attribute, StringRef String) {
-  if (String.size() > 3) {
-    MCSymbol *Symb = DD->getStringPoolEntry(String);
-    DIEValue *Value;
-    if (Asm->needsRelocationsForDwarfStringPool())
-      Value = new (DIEValueAllocator) DIELabel(Symb);
-    else {
-      MCSymbol *StringPool = DD->getStringPool();
-      Value = new (DIEValueAllocator) DIEDelta(Symb, StringPool);
-    }
-    Die->addValue(Attribute, dwarf::DW_FORM_strp, Value);
-  } else {
-    DIEValue *Value = new (DIEValueAllocator) DIEString(String);
-    Die->addValue(Attribute, dwarf::DW_FORM_string, Value);
+  MCSymbol *Symb = DD->getStringPoolEntry(String);
+  DIEValue *Value;
+  if (Asm->needsRelocationsForDwarfStringPool())
+    Value = new (DIEValueAllocator) DIELabel(Symb);
+  else {
+    MCSymbol *StringPool = DD->getStringPool();
+    Value = new (DIEValueAllocator) DIEDelta(Symb, StringPool);
   }
+  Die->addValue(Attribute, dwarf::DW_FORM_strp, Value);
 }
 
 /// addLabel - Add a Dwarf label attribute data and value.
diff --git a/test/CodeGen/ARM/2011-01-19-MergedGlobalDbg.ll b/test/CodeGen/ARM/2011-01-19-MergedGlobalDbg.ll
index 9484212..8b29c15 100644
--- a/test/CodeGen/ARM/2011-01-19-MergedGlobalDbg.ll
+++ b/test/CodeGen/ARM/2011-01-19-MergedGlobalDbg.ll
@@ -17,8 +17,7 @@ target triple = "thumbv7-apple-darwin10"
 ; DW_OP_constu
 ; offset
 
-;CHECK:        .ascii   "x2"                   @ DW_AT_name
-;CHECK-NEXT:        .byte   0
+;CHECK: .long Lset6
 ;CHECK-NEXT:        @ DW_AT_type
 ;CHECK-NEXT:        @ DW_AT_decl_file
 ;CHECK-NEXT:        @ DW_AT_decl_line
diff --git a/test/CodeGen/ARM/2011-08-02-MergedGlobalDbg.ll b/test/CodeGen/ARM/2011-08-02-MergedGlobalDbg.ll
index f681c34..f2b0c5d 100644
--- a/test/CodeGen/ARM/2011-08-02-MergedGlobalDbg.ll
+++ b/test/CodeGen/ARM/2011-08-02-MergedGlobalDbg.ll
@@ -8,8 +8,7 @@
 ; DW_OP_constu
 ; offset
 
-;CHECK:        .ascii   "x2"                   @ DW_AT_name
-;CHECK-NEXT:        .byte   0
+;CHECK: .long Lset33
 ;CHECK-NEXT:        @ DW_AT_type
 ;CHECK-NEXT:        @ DW_AT_decl_file
 ;CHECK-NEXT:        @ DW_AT_decl_line
diff --git a/test/CodeGen/X86/2010-08-10-DbgConstant.ll b/test/CodeGen/X86/2010-08-10-DbgConstant.ll
index d98ef14..f0dc347e 100644
--- a/test/CodeGen/X86/2010-08-10-DbgConstant.ll
+++ b/test/CodeGen/X86/2010-08-10-DbgConstant.ll
@@ -1,6 +1,6 @@
 ; RUN: llc  -march=x86 -O0 < %s | FileCheck %s
 ; CHECK: DW_TAG_constant
-; CHECK-NEXT: ascii	 "ro"                   #{{#?}} DW_AT_name
+; CHECK-NEXT: .long .Lstring3 #{{#?}} DW_AT_name
 
 define void @foo() nounwind ssp {
 entry:
diff --git a/test/CodeGen/X86/2011-01-24-DbgValue-Before-Use.ll b/test/CodeGen/X86/2011-01-24-DbgValue-Before-Use.ll
index 7f13411..166dcf2 100644
--- a/test/CodeGen/X86/2011-01-24-DbgValue-Before-Use.ll
+++ b/test/CodeGen/X86/2011-01-24-DbgValue-Before-Use.ll
@@ -4,8 +4,7 @@ target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f3
 target triple = "x86_64-apple-darwin10.0.0"
 
 ; Check debug info for variable z_s
-;CHECK:       .ascii   "z_s"                  ## DW_AT_name
-;CHECK-NEXT:  .byte   0
+;CHECK: .long Lset13
 ;CHECK-NEXT:  ## DW_AT_decl_file
 ;CHECK-NEXT:  ## DW_AT_decl_line
 ;CHECK-NEXT:  ## DW_AT_type
diff --git a/test/CodeGen/X86/dbg-value-inlined-parameter.ll b/test/CodeGen/X86/dbg-value-inlined-parameter.ll
index 481c4ba..d248a41 100644
--- a/test/CodeGen/X86/dbg-value-inlined-parameter.ll
+++ b/test/CodeGen/X86/dbg-value-inlined-parameter.ll
@@ -8,7 +8,7 @@
 ;CHECK-NEXT: DW_AT_call_file
 ;CHECK-NEXT: DW_AT_call_line
 ;CHECK-NEXT: DW_TAG_formal_parameter
-;CHECK-NEXT: .ascii   "sp"                   ## DW_AT_name
+;CHECK-NEXT: Lstring11-Lsection_str ## DW_AT_name
 
 %struct.S1 = type { float*, i32 }
 
diff --git a/test/CodeGen/X86/dbg-value-location.ll b/test/CodeGen/X86/dbg-value-location.ll
index a0e4d16..05e29ec 100644
--- a/test/CodeGen/X86/dbg-value-location.ll
+++ b/test/CodeGen/X86/dbg-value-location.ll
@@ -4,8 +4,7 @@ target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f3
 target triple = "x86_64-apple-darwin10.0.0"
 ;Radar 8950491
 
-;CHECK:        .ascii   "var"                  ## DW_AT_name
-;CHECK-NEXT:        .byte   0
+;CHECK: .long Lset5
 ;CHECK-NEXT:        ## DW_AT_decl_file
 ;CHECK-NEXT:        ## DW_AT_decl_line
 ;CHECK-NEXT:        ## DW_AT_type
diff --git a/test/DebugInfo/2011-09-26-GlobalVarContext.ll b/test/DebugInfo/2011-09-26-GlobalVarContext.ll
index 1452ff9..934fa81 100644
--- a/test/DebugInfo/2011-09-26-GlobalVarContext.ll
+++ b/test/DebugInfo/2011-09-26-GlobalVarContext.ll
@@ -1,4 +1,4 @@
-; RUN: llc -asm-verbose %s -o - | FileCheck %s
+; RUN: llc -mtriple=x86_64-pc-linux-gnu -asm-verbose %s -o - | FileCheck %s
 
 ; ModuleID = 'test.c'
 
@@ -38,10 +38,10 @@ declare void @llvm.dbg.declare(metadata, metadata) nounwind readnone
 !18 = metadata !{i32 4, i32 23, metadata !16, null}
 !19 = metadata !{i32 5, i32 5, metadata !16, null}
 
-; CHECK: .ascii	 "GLB"
+; CHECK: .long .Lstring3
 ; CHECK: .byte	1
 ; CHECK: .byte	1
 
-; CHECK: .ascii	 "LOC"
+; CHECK: .long .Lstring6
 ; CHECK: .byte	1
 ; CHECK: .byte	4
diff --git a/test/DebugInfo/stringpool.ll b/test/DebugInfo/stringpool.ll
index 0a7c979..2cd1001 100644
--- a/test/DebugInfo/stringpool.ll
+++ b/test/DebugInfo/stringpool.ll
@@ -1,54 +1,44 @@
-; RUN: llc -O0 -mtriple=x86_64-unknown-linux-gnu < %s | FileCheck %s --check-prefix=LINUX
-; RUN: llc -O0 -mtriple=x86_64-darwin < %s | FileCheck %s --check-prefix=DARWIN
-target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64-S128"
-target triple = "x86_64-unknown-linux-gnu"
+; RUN: llc -mtriple=x86_64-unknown-linux-gnu < %s | FileCheck %s --check-prefix=LINUX
+; RUN: llc -mtriple=x86_64-darwin < %s | FileCheck %s --check-prefix=DARWIN
 
-@x = common global i32 0, align 4
-@yyyyyyyy = common global i32 0, align 4
+@yyyy = common global i32 0, align 4
 
 !llvm.dbg.cu = !{!0}
 
-!0 = metadata !{i32 720913, i32 0, i32 12, metadata !"hello.c", metadata !"/home/nlewycky", metadata !"clang version 3.1 (trunk 143048)", i1 true, i1 true, metadata !"", i32 0, metadata !1, metadata !1, metadata !1, metadata !3} ; [ DW_TAG_compile_unit ]
+!0 = metadata !{i32 720913, i32 0, i32 12, metadata !"z.c", metadata !"/home/nicholas", metadata !"clang version 3.1 (trunk 143009)", i1 true, i1 true, metadata !"", i32 0, metadata !1, metadata !1, metadata !1, metadata !3} ; [ DW_TAG_compile_unit ]
 !1 = metadata !{metadata !2}
 !2 = metadata !{i32 0}
 !3 = metadata !{metadata !4}
-!4 = metadata !{metadata !5, metadata !8}
-!5 = metadata !{i32 720948, i32 0, null, metadata !"x", metadata !"x", metadata !"", metadata !6, i32 1, metadata !7, i32 0, i32 1, i32* @x} ; [ DW_TAG_variable ]
-!6 = metadata !{i32 720937, metadata !"hello.c", metadata !"/home/nlewycky", null} ; [ DW_TAG_file_type ]
+!4 = metadata !{metadata !5}
+!5 = metadata !{i32 720948, i32 0, null, metadata !"yyyy", metadata !"yyyy", metadata !"", metadata !6, i32 1, metadata !7, i32 0, i32 1, i32* @yyyy} ; [ DW_TAG_variable ]
+!6 = metadata !{i32 720937, metadata !"z.c", metadata !"/home/nicholas", null} ; [ DW_TAG_file_type ]
 !7 = metadata !{i32 720932, null, metadata !"int", null, i32 0, i64 32, i64 32, i64 0, i32 0, i32 5} ; [ DW_TAG_base_type ]
-!8 = metadata !{i32 720948, i32 0, null, metadata !"yyyyyyyy", metadata !"yyyyyyyy", metadata !"", metadata !6, i32 2, metadata !7, i32 0, i32 1, i32* @yyyyyyyy} ; [ DW_TAG_variable ]
 
-; 120 is ASCII 'x'. Verify that we use it directly as its name and don't emit
-; a reference to the string pool.
-; LINUX:        .byte   120                     # DW_AT_name
-; DARWIN:       .byte   120                     ## DW_AT_name
-
-; Verify that we refer to 'yyyyyyyy' with a relocation.
-; LINUX:      .long   .Lstring{{[0-9]+}}      # DW_AT_name
+; Verify that we refer to 'yyyy' with a relocation.
+; LINUX:      .long   .Lstring3               # DW_AT_name
 ; LINUX-NEXT: .long   39                      # DW_AT_type
 ; LINUX-NEXT: .byte   1                       # DW_AT_external
 ; LINUX-NEXT: .byte   1                       # DW_AT_decl_file
-; LINUX-NEXT: .byte   2                       # DW_AT_decl_line
+; LINUX-NEXT: .byte   1                       # DW_AT_decl_line
 ; LINUX-NEXT: .byte   9                       # DW_AT_location
 ; LINUX-NEXT: .byte   3
-; LINUX-NEXT: .quad   yyyyyyyy
+; LINUX-NEXT: .quad   yyyy
 
-; Verify that we refer to 'yyyyyyyy' without a relocation.
-; DARWIN: Lset[[N:[0-9]+]] = Lstring{{[0-9]+}}-Lsection_str   ## DW_AT_name
-; DARWIN-NEXT:        .long   Lset[[N]]
+; Verify that we refer to 'yyyy' without a relocation.
+; DARWIN: Lset5 = Lstring3-Lsection_str               ## DW_AT_name
+; DARWIN-NEXT:        .long   Lset5
 ; DARWIN-NEXT:        .long   39                      ## DW_AT_type
 ; DARWIN-NEXT:        .byte   1                       ## DW_AT_external
 ; DARWIN-NEXT:        .byte   1                       ## DW_AT_decl_file
-; DARWIN-NEXT:        .byte   2                       ## DW_AT_decl_line
+; DARWIN-NEXT:        .byte   1                       ## DW_AT_decl_line
 ; DARWIN-NEXT:        .byte   9                       ## DW_AT_location
 ; DARWIN-NEXT:        .byte   3
-; DARWIN-NEXT:        .quad   _yyyyyyyy
-
+; DARWIN-NEXT:        .quad   _yyyy
 
-; Verify that "yyyyyyyy" ended up in the stringpool.
+; Verify that "yyyy" ended up in the stringpool.
 ; LINUX: .section .debug_str,"MS",@progbits,1
 ; LINUX-NOT: .section
-; LINUX: yyyyyyyy
+; LINUX: yyyy
 ; DARWIN: .section __DWARF,__debug_str,regular,debug
 ; DARWIN-NOT: .section
-; DARWIN: yyyyyyyy
+; DARWIN: yyyy