Fix debug info for merged global.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123862 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/CodeGen/AsmPrinter/DwarfDebug.cpp b/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
index fdd47f2..5c63ab5 100644 (file)
--- a/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
+++ b/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
@@ -16,6 +16,7 @@
 #include "DIE.h"
 #include "llvm/Constants.h"
 #include "llvm/Module.h"
+#include "llvm/Instructions.h"
 #include "llvm/CodeGen/MachineFunction.h"
 #include "llvm/CodeGen/MachineModuleInfo.h"
 #include "llvm/MC/MCAsmInfo.h"
@@ -1922,6 +1923,32 @@ static bool isUnsignedDIType(DIType Ty) {
   return false;
 }
 
+// Return const exprssion if value is a GEP to access merged global
+// constant. e.g.
+// i8* getelementptr ({ i8, i8, i8, i8 }* @_MergedGlobals, i32 0, i32 0)
+static const ConstantExpr *getMergedGlobalExpr(const Value *V) {
+  const ConstantExpr *CE = dyn_cast_or_null<ConstantExpr>(V);
+  if (!CE || CE->getNumOperands() != 3 ||
+      CE->getOpcode() != Instruction::GetElementPtr)
+    return NULL;
+
+  // First operand points to a global value.
+  if (!isa<GlobalValue>(CE->getOperand(0)))
+    return NULL;
+
+  // Second operand is zero.
+  const ConstantInt *CI = 
+    dyn_cast_or_null<ConstantInt>(CE->getOperand(1));
+  if (!CI || !CI->isZero())
+    return NULL;
+
+  // Third operand is offset.
+  if (!isa<ConstantInt>(CE->getOperand(2)))
+    return NULL;
+
+  return CE;
+}
+
 /// constructGlobalVariableDIE - Construct global variable DIE.
 void DwarfDebug::constructGlobalVariableDIE(const MDNode *N) {
   DIGlobalVariable GV(N);
@@ -1991,6 +2018,18 @@ void DwarfDebug::constructGlobalVariableDIE(const MDNode *N) {
   } else if (ConstantInt *CI = 
              dyn_cast_or_null<ConstantInt>(GV.getConstant()))
     addConstantValue(VariableDIE, CI, isUnsignedDIType(GTy));
+  else if (const ConstantExpr *CE = getMergedGlobalExpr(N->getOperand(11))) {
+    // GV is a merged global.
+    DIEBlock *Block = new (DIEValueAllocator) DIEBlock();
+    addUInt(Block, 0, dwarf::DW_FORM_data1, dwarf::DW_OP_addr);
+    addLabel(Block, 0, dwarf::DW_FORM_udata,
+             Asm->Mang->getSymbol(cast<GlobalValue>(CE->getOperand(0))));
+    ConstantInt *CII = cast<ConstantInt>(CE->getOperand(2));
+    addUInt(Block, 0, dwarf::DW_FORM_data1, dwarf::DW_OP_constu);
+    addUInt(Block, 0, dwarf::DW_FORM_udata, CII->getZExtValue());
+    addUInt(Block, 0, dwarf::DW_FORM_data1, dwarf::DW_OP_plus);
+    addBlock(VariableDIE, dwarf::DW_AT_location, 0, Block);
+  }
 
   return;
 }

diff --git a/test/CodeGen/ARM/2011-01-19-MergedGlobalDbg.ll b/test/CodeGen/ARM/2011-01-19-MergedGlobalDbg.ll
new file mode 100644 (file)
index 0000000..99baad2
--- /dev/null
+++ b/test/CodeGen/ARM/2011-01-19-MergedGlobalDbg.ll
@@ -0,0 +1,127 @@
+; RUN: llc < %s | FileCheck %s
+
+target datalayout = "e-p:32:32:32-i1:8:32-i8:8:32-i16:16:32-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:32:64-v128:32:128-a0:0:32-n32"
+target triple = "thumbv7-apple-darwin10"
+
+@x1 = internal global i8 1
+@x2 = internal global i8 1
+@x3 = internal global i8 1
+@x4 = internal global i8 1
+@x5 = global i8 1
+
+; Check debug info output for merged global.
+; DW_AT_location
+; DW_OP_addr
+; DW_OP_plus
+; .long __MergedGlobals
+; DW_OP_constu
+; offset
+
+;CHECK:        .byte   7                       @ Abbrev [7] 0x1a5:0x13 DW_TAG_variable
+;CHECK-NEXT:        .ascii   "x2"                   @ DW_AT_name
+;CHECK-NEXT:        .byte   0
+;CHECK-NEXT:        .long   93                      @ DW_AT_type
+;CHECK-NEXT:        .byte   1                       @ DW_AT_decl_file
+;CHECK-NEXT:        .byte   6                       @ DW_AT_decl_line
+;CHECK-NEXT:        .byte   8                       @ DW_AT_location
+;CHECK-NEXT:        .byte   3
+;CHECK-NEXT:        .long   __MergedGlobals
+;CHECK-NEXT:        .byte   16
+;CHECK-NEXT:        .byte   1
+;CHECK-NEXT:        .byte   34
+
+define zeroext i8 @get1(i8 zeroext %a) nounwind optsize {
+entry:
+  tail call void @llvm.dbg.value(metadata !{i8 %a}, i64 0, metadata !10), !dbg !30
+  %0 = load i8* @x1, align 4, !dbg !30
+  tail call void @llvm.dbg.value(metadata !{i8 %0}, i64 0, metadata !11), !dbg !30
+  store i8 %a, i8* @x1, align 4, !dbg !30
+  ret i8 %0, !dbg !31
+}
+
+declare void @llvm.dbg.value(metadata, i64, metadata) nounwind readnone
+
+define zeroext i8 @get2(i8 zeroext %a) nounwind optsize {
+entry:
+  tail call void @llvm.dbg.value(metadata !{i8 %a}, i64 0, metadata !18), !dbg !32
+  %0 = load i8* @x2, align 4, !dbg !32
+  tail call void @llvm.dbg.value(metadata !{i8 %0}, i64 0, metadata !19), !dbg !32
+  store i8 %a, i8* @x2, align 4, !dbg !32
+  ret i8 %0, !dbg !33
+}
+
+define zeroext i8 @get3(i8 zeroext %a) nounwind optsize {
+entry:
+  tail call void @llvm.dbg.value(metadata !{i8 %a}, i64 0, metadata !21), !dbg !34
+  %0 = load i8* @x3, align 4, !dbg !34
+  tail call void @llvm.dbg.value(metadata !{i8 %0}, i64 0, metadata !22), !dbg !34
+  store i8 %a, i8* @x3, align 4, !dbg !34
+  ret i8 %0, !dbg !35
+}
+
+define zeroext i8 @get4(i8 zeroext %a) nounwind optsize {
+entry:
+  tail call void @llvm.dbg.value(metadata !{i8 %a}, i64 0, metadata !24), !dbg !36
+  %0 = load i8* @x4, align 4, !dbg !36
+  tail call void @llvm.dbg.value(metadata !{i8 %0}, i64 0, metadata !25), !dbg !36
+  store i8 %a, i8* @x4, align 4, !dbg !36
+  ret i8 %0, !dbg !37
+}
+
+define zeroext i8 @get5(i8 zeroext %a) nounwind optsize {
+entry:
+  tail call void @llvm.dbg.value(metadata !{i8 %a}, i64 0, metadata !27), !dbg !38
+  %0 = load i8* @x5, align 4, !dbg !38
+  tail call void @llvm.dbg.value(metadata !{i8 %0}, i64 0, metadata !28), !dbg !38
+  store i8 %a, i8* @x5, align 4, !dbg !38
+  ret i8 %0, !dbg !39
+}
+
+!llvm.dbg.sp = !{!0, !6, !7, !8, !9}
+!llvm.dbg.lv.get1 = !{!10, !11}
+!llvm.dbg.gv = !{!13, !14, !15, !16, !17}
+!llvm.dbg.lv.get2 = !{!18, !19}
+!llvm.dbg.lv.get3 = !{!21, !22}
+!llvm.dbg.lv.get4 = !{!24, !25}
+!llvm.dbg.lv.get5 = !{!27, !28}
+
+!0 = metadata !{i32 589870, i32 0, metadata !1, metadata !"get1", metadata !"get1", metadata !"get1", metadata !1, i32 4, metadata !3, i1 false, i1 true, i32 0, i32 0, null, i32 256, i1 true, i8 (i8)* @get1} ; [ DW_TAG_subprogram ]
+!1 = metadata !{i32 589865, metadata !"foo.c", metadata !"/tmp/", metadata !2} ; [ DW_TAG_file_type ]
+!2 = metadata !{i32 589841, i32 0, i32 1, metadata !"foo.c", metadata !"/tmp/", metadata !"4.2.1 (Based on Apple Inc. build 5658) (LLVM build 2369.8)", i1 true, i1 true, metadata !"", i32 0} ; [ DW_TAG_compile_unit ]
+!3 = metadata !{i32 589845, metadata !1, metadata !"", metadata !1, i32 0, i64 0, i64 0, i64 0, i32 0, null, metadata !4, i32 0, null} ; [ DW_TAG_subroutine_type ]
+!4 = metadata !{metadata !5, metadata !5}
+!5 = metadata !{i32 589860, metadata !1, metadata !"_Bool", metadata !1, i32 0, i64 8, i64 8, i64 0, i32 0, i32 2} ; [ DW_TAG_base_type ]
+!6 = metadata !{i32 589870, i32 0, metadata !1, metadata !"get2", metadata !"get2", metadata !"get2", metadata !1, i32 7, metadata !3, i1 false, i1 true, i32 0, i32 0, null, i32 256, i1 true, i8 (i8)* @get2} ; [ DW_TAG_subprogram ]
+!7 = metadata !{i32 589870, i32 0, metadata !1, metadata !"get3", metadata !"get3", metadata !"get3", metadata !1, i32 10, metadata !3, i1 false, i1 true, i32 0, i32 0, null, i32 256, i1 true, i8 (i8)* @get3} ; [ DW_TAG_subprogram ]
+!8 = metadata !{i32 589870, i32 0, metadata !1, metadata !"get4", metadata !"get4", metadata !"get4", metadata !1, i32 13, metadata !3, i1 false, i1 true, i32 0, i32 0, null, i32 256, i1 true, i8 (i8)* @get4} ; [ DW_TAG_subprogram ]
+!9 = metadata !{i32 589870, i32 0, metadata !1, metadata !"get5", metadata !"get5", metadata !"get5", metadata !1, i32 16, metadata !3, i1 false, i1 true, i32 0, i32 0, null, i32 256, i1 true, i8 (i8)* @get5} ; [ DW_TAG_subprogram ]
+!10 = metadata !{i32 590081, metadata !0, metadata !"a", metadata !1, i32 4, metadata !5, i32 0} ; [ DW_TAG_arg_variable ]
+!11 = metadata !{i32 590080, metadata !12, metadata !"b", metadata !1, i32 4, metadata !5, i32 0} ; [ DW_TAG_auto_variable ]
+!12 = metadata !{i32 589835, metadata !0, i32 4, i32 0, metadata !1, i32 0} ; [ DW_TAG_lexical_block ]
+!13 = metadata !{i32 589876, i32 0, metadata !1, metadata !"x1", metadata !"x1", metadata !"", metadata !1, i32 3, metadata !5, i1 true, i1 true, i8* @x1} ; [ DW_TAG_variable ]
+!14 = metadata !{i32 589876, i32 0, metadata !1, metadata !"x2", metadata !"x2", metadata !"", metadata !1, i32 6, metadata !5, i1 true, i1 true, i8* @x2} ; [ DW_TAG_variable ]
+!15 = metadata !{i32 589876, i32 0, metadata !1, metadata !"x3", metadata !"x3", metadata !"", metadata !1, i32 9, metadata !5, i1 true, i1 true, i8* @x3} ; [ DW_TAG_variable ]
+!16 = metadata !{i32 589876, i32 0, metadata !1, metadata !"x4", metadata !"x4", metadata !"", metadata !1, i32 12, metadata !5, i1 true, i1 true, i8* @x4} ; [ DW_TAG_variable ]
+!17 = metadata !{i32 589876, i32 0, metadata !1, metadata !"x5", metadata !"x5", metadata !"", metadata !1, i32 15, metadata !5, i1 false, i1 true, i8* @x5} ; [ DW_TAG_variable ]
+!18 = metadata !{i32 590081, metadata !6, metadata !"a", metadata !1, i32 7, metadata !5, i32 0} ; [ DW_TAG_arg_variable ]
+!19 = metadata !{i32 590080, metadata !20, metadata !"b", metadata !1, i32 7, metadata !5, i32 0} ; [ DW_TAG_auto_variable ]
+!20 = metadata !{i32 589835, metadata !6, i32 7, i32 0, metadata !1, i32 1} ; [ DW_TAG_lexical_block ]
+!21 = metadata !{i32 590081, metadata !7, metadata !"a", metadata !1, i32 10, metadata !5, i32 0} ; [ DW_TAG_arg_variable ]
+!22 = metadata !{i32 590080, metadata !23, metadata !"b", metadata !1, i32 10, metadata !5, i32 0} ; [ DW_TAG_auto_variable ]
+!23 = metadata !{i32 589835, metadata !7, i32 10, i32 0, metadata !1, i32 2} ; [ DW_TAG_lexical_block ]
+!24 = metadata !{i32 590081, metadata !8, metadata !"a", metadata !1, i32 13, metadata !5, i32 0} ; [ DW_TAG_arg_variable ]
+!25 = metadata !{i32 590080, metadata !26, metadata !"b", metadata !1, i32 13, metadata !5, i32 0} ; [ DW_TAG_auto_variable ]
+!26 = metadata !{i32 589835, metadata !8, i32 13, i32 0, metadata !1, i32 3} ; [ DW_TAG_lexical_block ]
+!27 = metadata !{i32 590081, metadata !9, metadata !"a", metadata !1, i32 16, metadata !5, i32 0} ; [ DW_TAG_arg_variable ]
+!28 = metadata !{i32 590080, metadata !29, metadata !"b", metadata !1, i32 16, metadata !5, i32 0} ; [ DW_TAG_auto_variable ]
+!29 = metadata !{i32 589835, metadata !9, i32 16, i32 0, metadata !1, i32 4} ; [ DW_TAG_lexical_block ]
+!30 = metadata !{i32 4, i32 0, metadata !0, null}
+!31 = metadata !{i32 4, i32 0, metadata !12, null}
+!32 = metadata !{i32 7, i32 0, metadata !6, null}
+!33 = metadata !{i32 7, i32 0, metadata !20, null}
+!34 = metadata !{i32 10, i32 0, metadata !7, null}
+!35 = metadata !{i32 10, i32 0, metadata !23, null}
+!36 = metadata !{i32 13, i32 0, metadata !8, null}
+!37 = metadata !{i32 13, i32 0, metadata !26, null}
+!38 = metadata !{i32 16, i32 0, metadata !9, null}
+!39 = metadata !{i32 16, i32 0, metadata !29, null}