[llvm] r348898 - Revert "debuginfo: Use symbol difference for CU length to simplify assembly reading/editing"

[Jordan Rupprecht via llvm-commits]

Author: rupprecht
Date: Tue Dec 11 13:26:52 2018
New Revision: 348898

URL: http://llvm.org/viewvc/llvm-project?rev=348898&view=rev
Log:
 Revert "debuginfo: Use symbol difference for CU length to simplify assembly reading/editing"

Temporarily reverts commit r348806 due to strange asm compilation issues in certain modes (combination of asan+cuda+other things). Will provide repro soon.

Modified:
    llvm/trunk/lib/CodeGen/AsmPrinter/DwarfFile.cpp
    llvm/trunk/lib/CodeGen/AsmPrinter/DwarfUnit.cpp
    llvm/trunk/lib/CodeGen/AsmPrinter/DwarfUnit.h
    llvm/trunk/test/DebugInfo/X86/sections_as_references.ll

Modified: llvm/trunk/lib/CodeGen/AsmPrinter/DwarfFile.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/AsmPrinter/DwarfFile.cpp?rev=348898&r1=348897&r2=348898&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/AsmPrinter/DwarfFile.cpp (original)
+++ llvm/trunk/lib/CodeGen/AsmPrinter/DwarfFile.cpp Tue Dec 11 13:26:52 2018
@@ -46,8 +46,6 @@ void DwarfFile::emitUnit(DwarfUnit *TheU
   TheU->emitHeader(UseOffsets);
 
   Asm->emitDwarfDIE(Die);
-
-  Asm->OutStreamer->EmitLabel(TheU->getEndLabel());
 }
 
 // Compute the size and offset for each DIE.

Modified: llvm/trunk/lib/CodeGen/AsmPrinter/DwarfUnit.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/AsmPrinter/DwarfUnit.cpp?rev=348898&r1=348897&r2=348898&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/AsmPrinter/DwarfUnit.cpp (original)
+++ llvm/trunk/lib/CodeGen/AsmPrinter/DwarfUnit.cpp Tue Dec 11 13:26:52 2018
@@ -38,7 +38,6 @@
 #include "llvm/Support/Casting.h"
 #include "llvm/Support/CommandLine.h"
 #include "llvm/Target/TargetLoweringObjectFile.h"
-#include "llvm/Target/TargetMachine.h"
 #include <cassert>
 #include <cstdint>
 #include <string>
@@ -1554,17 +1553,7 @@ DIE *DwarfUnit::getOrCreateStaticMemberD
 void DwarfUnit::emitCommonHeader(bool UseOffsets, dwarf::UnitType UT) {
   // Emit size of content not including length itself
   Asm->OutStreamer->AddComment("Length of Unit");
-  StringRef Prefix = isDwoUnit() ? "debug_info_dwo_" : "debug_info_";
-  MCSymbol *BeginLabel = Asm->createTempSymbol(Prefix + "start");
-  EndLabel = Asm->createTempSymbol(Prefix + "end");
-
-  // Use a label difference for the convenience of legible/easily modified
-  // assembly - except on NVPTX where label differences aren't supported.
-  if (Asm->TM.getTargetTriple().isNVPTX())
-    Asm->emitInt32(getHeaderSize() + getUnitDie().getSize());
-  else
-    Asm->EmitLabelDifference(EndLabel, BeginLabel, 4);
-  Asm->OutStreamer->EmitLabel(BeginLabel);
+  Asm->emitInt32(getHeaderSize() + getUnitDie().getSize());
 
   Asm->OutStreamer->AddComment("DWARF version number");
   unsigned Version = DD->getDwarfVersion();

Modified: llvm/trunk/lib/CodeGen/AsmPrinter/DwarfUnit.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/AsmPrinter/DwarfUnit.h?rev=348898&r1=348897&r2=348898&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/AsmPrinter/DwarfUnit.h (original)
+++ llvm/trunk/lib/CodeGen/AsmPrinter/DwarfUnit.h Tue Dec 11 13:26:52 2018
@@ -48,7 +48,6 @@ protected:
 
   /// Target of Dwarf emission.
   AsmPrinter *Asm;
-  MCSymbol *EndLabel;
 
   // Holders for some common dwarf information.
   DwarfDebug *DD;
@@ -83,7 +82,6 @@ protected:
 public:
   // Accessors.
   AsmPrinter* getAsmPrinter() const { return Asm; }
-  MCSymbol *getEndLabel() const { return EndLabel; }
   uint16_t getLanguage() const { return CUNode->getSourceLanguage(); }
   const DICompileUnit *getCUNode() const { return CUNode; }
 

Modified: llvm/trunk/test/DebugInfo/X86/sections_as_references.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/DebugInfo/X86/sections_as_references.ll?rev=348898&r1=348897&r2=348898&view=diff
==============================================================================
--- llvm/trunk/test/DebugInfo/X86/sections_as_references.ll (original)
+++ llvm/trunk/test/DebugInfo/X86/sections_as_references.ll Tue Dec 11 13:26:52 2018
@@ -9,19 +9,13 @@
 ; CHECK-NOT: .L
 
 ; CHECK:      .section .debug_info
-; CHECK-NEXT: .long .Ldebug_info_end0-.Ldebug_info_start0 # Length of Unit
-; CHECK-NEXT: .Ldebug_info_start0:
-; CHECK-NEXT: .short 2             # DWARF version number
+; CHECK-NOT:  .L
+; CHECK:      .short 2             # DWARF version number
 ; CHECK-NOT:  .L
 ; CHECK:      .long .debug_abbrev  # Offset Into Abbrev. Section
 ; CHECK-NOT:  .L
 ; CHECK:      .long .debug_line    # DW_AT_stmt_list
 ; CHECK-NOT:  .L
-; CHECK:      .Ldebug_info_end0:
-; CHECK-NOT:  .L
-; CHECK:      .long .Ldebug_info_end1-.Ldebug_info_start1 # Length of Unit
-; CHECK-NEXT: .Ldebug_info_start1:
-; CHECK-NOT:  .L
 ; CHECK:      .long .debug_abbrev  # Offset Into Abbrev. Section
 ; CHECK-NOT:  .L
 ; CHECK:      .long .debug_line    # DW_AT_stmt_list
@@ -29,7 +23,6 @@
 ; CHECK:      .quad .debug_info+{{[0-9]+}} # DW_AT_type
 ; CHECK-NOT:  .L
 ; CHECK:      .byte 0              # End Of Children Mark
-; CHECK-NEXT: .Ldebug_info_end1:
 ; CHECK-NOT:  .L
 
 source_filename = "test/DebugInfo/X86/sections_as_references.ll"