[DebugInfo] Add DILabel metadata and intrinsic llvm.dbg.label.

In order to set breakpoints on labels and list source code around
labels, we need collect debug information for labels, i.e., label
name, the function label belong, line number in the file, and the
address label located. In order to keep these information in LLVM
IR and to allow backend to generate debug information correctly.
We create a new kind of metadata for labels, DILabel. The format
of DILabel is

!DILabel(scope: !1, name: "foo", file: !2, line: 3)

We hope to keep debug information as much as possible even the
code is optimized. So, we create a new kind of intrinsic for label
metadata to avoid the metadata is eliminated with basic block.
The intrinsic will keep existing if we keep it from optimized out.
The format of the intrinsic is

llvm.dbg.label(metadata !1)

It has only one argument, that is the DILabel metadata. The
intrinsic will follow the label immediately. Backend could get the
label metadata through the intrinsic's parameter.

We also create DIBuilder API for labels to be used by Frontend.
Frontend could use createLabel() to allocate DILabel objects, and use
insertLabel() to insert llvm.dbg.label intrinsic in LLVM IR.

Differential Revision: https://reviews.llvm.org/D45024

Patch by Hsiangkai Wang.

llvm-svn: 331841

6 files changed, 7 insertions, 7 deletions

diff --git a/llvm/test/Bitcode/DILocalVariable-explicit-tags.ll b/llvm/test/Bitcode/DILocalVariable-explicit-tags.ll
index b3e793d4cb4..a42884cc427 100644
--- a/llvm/test/Bitcode/DILocalVariable-explicit-tags.ll
+++ b/llvm/test/Bitcode/DILocalVariable-explicit-tags.ll
@@ -3,7 +3,7 @@
 ;
 ; RUN: llvm-dis < %s.bc -o - | llvm-as | llvm-dis | FileCheck %s
 
-; CHECK: ![[SP:[0-9]+]] = distinct !DISubprogram(name: "foo",{{.*}} variables: ![[VARS:[0-9]+]]
+; CHECK: ![[SP:[0-9]+]] = distinct !DISubprogram(name: "foo",{{.*}} retainedNodes: ![[VARS:[0-9]+]]
 ; CHECK: ![[VARS]] = !{![[PARAM:[0-9]+]], ![[AUTO:[0-9]+]]}
 ; CHECK: ![[PARAM]] = !DILocalVariable(name: "param", arg: 1, scope: ![[SP]])
 ; CHECK: ![[AUTO]]  = !DILocalVariable(name: "auto", scope: ![[SP]])
@@ -13,7 +13,7 @@
 !llvm.module.flags = !{!6}
 !llvm.dbg.cu = !{!4}
 
-!0 = distinct !DISubprogram(name: "foo", scope: null, isLocal: false, isDefinition: true, isOptimized: false, variables: !1)
+!0 = distinct !DISubprogram(name: "foo", scope: null, isLocal: false, isDefinition: true, isOptimized: false, retainedNodes: !1)
 !1 = !{!2, !3}
 !2 = !DILocalVariable(tag: DW_TAG_arg_variable, name: "param", arg: 1, scope: !0)
 !3 = !DILocalVariable(tag: DW_TAG_auto_variable, name: "auto", scope: !0)
diff --git a/llvm/test/Bitcode/dilocalvariable-3.9.ll b/llvm/test/Bitcode/dilocalvariable-3.9.ll
index 2e39a2f5242..99f99db0637 100644
--- a/llvm/test/Bitcode/dilocalvariable-3.9.ll
+++ b/llvm/test/Bitcode/dilocalvariable-3.9.ll
@@ -13,7 +13,7 @@
 !3 = !{i32 2, !"Dwarf Version", i32 4}
 !4 = !{i32 2, !"Debug Info Version", i32 3}
 !5 = !{!"clang version 3.9.1 (http://llvm.org/git/clang.git c3709e72d22432f53f8e2f14354def31a96734fe)"}
-!6 = distinct !DISubprogram(name: "f", scope: !1, file: !1, line: 1, type: !7, isLocal: false, isDefinition: true, scopeLine: 1, isOptimized: false, unit: !0, variables: !2)
+!6 = distinct !DISubprogram(name: "f", scope: !1, file: !1, line: 1, type: !7, isLocal: false, isDefinition: true, scopeLine: 1, isOptimized: false, unit: !0, retainedNodes: !2)
 !7 = !DISubroutineType(types: !8)
 !8 = !{null}
 !9 = !DILocalVariable(name: "i", scope: !6, file: !1, line: 1, type: !10)
diff --git a/llvm/test/Bitcode/disubrange-v0.ll b/llvm/test/Bitcode/disubrange-v0.ll
index 2d4cd187144..c50d406c59b 100644
--- a/llvm/test/Bitcode/disubrange-v0.ll
+++ b/llvm/test/Bitcode/disubrange-v0.ll
@@ -22,7 +22,7 @@ declare void @llvm.dbg.declare(metadata, metadata, metadata) #1
 !4 = !{i32 2, !"Debug Info Version", i32 3}
 !5 = !{i32 1, !"wchar_size", i32 4}
 !6 = !{!"clang version 5.0.1"}
-!7 = distinct !DISubprogram(name: "foo", scope: !1, file: !1, line: 20, type: !8, isLocal: false, isDefinition: true, scopeLine: 20, flags: DIFlagPrototyped, isOptimized: false, unit: !0, variables: !11)
+!7 = distinct !DISubprogram(name: "foo", scope: !1, file: !1, line: 20, type: !8, isLocal: false, isDefinition: true, scopeLine: 20, flags: DIFlagPrototyped, isOptimized: false, unit: !0, retainedNodes: !11)
 !8 = !DISubroutineType(types: !9)
 !9 = !{null, !10}
 !10 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
diff --git a/llvm/test/Bitcode/disubrange.ll b/llvm/test/Bitcode/disubrange.ll
index 5c725099ae3..b41257ef4bd 100644
--- a/llvm/test/Bitcode/disubrange.ll
+++ b/llvm/test/Bitcode/disubrange.ll
@@ -23,7 +23,7 @@ declare void @llvm.dbg.declare(metadata, metadata, metadata) #1
 !4 = !{i32 2, !"Debug Info Version", i32 3}
 !5 = !{i32 1, !"wchar_size", i32 4}
 !6 = !{!"clang version 5.0.1"}
-!7 = distinct !DISubprogram(name: "foo", scope: !1, file: !1, line: 20, type: !8, isLocal: false, isDefinition: true, scopeLine: 20, flags: DIFlagPrototyped, isOptimized: false, unit: !0, variables: !11)
+!7 = distinct !DISubprogram(name: "foo", scope: !1, file: !1, line: 20, type: !8, isLocal: false, isDefinition: true, scopeLine: 20, flags: DIFlagPrototyped, isOptimized: false, unit: !0, retainedNodes: !11)
 !8 = !DISubroutineType(types: !9)
 !9 = !{null, !10}
 !10 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
diff --git a/llvm/test/Bitcode/upgrade-dbg-value.ll b/llvm/test/Bitcode/upgrade-dbg-value.ll
index 2a3a6369ae8..6e29e6f76b6 100644
--- a/llvm/test/Bitcode/upgrade-dbg-value.ll
+++ b/llvm/test/Bitcode/upgrade-dbg-value.ll
@@ -22,7 +22,7 @@ declare void @llvm.dbg.value(metadata, i64, metadata, metadata)
 !0 = distinct !DICompileUnit(language: DW_LANG_C99, file: !1, producer: "llc r309174", isOptimized: false, runtimeVersion: 0, emissionKind: FullDebug)
 !1 = !DIFile(filename: "a.c", directory: "/")
 !2 = !{i32 1, !"Debug Info Version", i32 3}
-!3 = distinct !DISubprogram(name: "f", scope: !1, file: !1, line: 1, type: !4, isLocal: false, isDefinition: true, isOptimized: false, unit: !0, variables: !7)
+!3 = distinct !DISubprogram(name: "f", scope: !1, file: !1, line: 1, type: !4, isLocal: false, isDefinition: true, isOptimized: false, unit: !0, retainedNodes: !7)
 !4 = !DISubroutineType(types: !5)
 !5 = !{!6}
 !6 = !DIBasicType(name: "int", size: 32, align: 32, encoding: DW_ATE_signed)
diff --git a/llvm/test/Bitcode/upgrade-subprogram-this.ll b/llvm/test/Bitcode/upgrade-subprogram-this.ll
index d84aa0aad44..81da5b06221 100644
--- a/llvm/test/Bitcode/upgrade-subprogram-this.ll
+++ b/llvm/test/Bitcode/upgrade-subprogram-this.ll
@@ -24,7 +24,7 @@ entry:
 !1 = !DIFile(filename: "t.cpp", directory: "D:\5Csrc\5Cllvm\5Cbuild")
 !2 = !{}
 !4 = !{i32 2, !"Debug Info Version", i32 3}
-!7 = distinct !DISubprogram(name: "f", linkageName: "\01?f@@YAXXZ", scope: !1, file: !1, line: 1, type: !8, isLocal: false, isDefinition: true, scopeLine: 1, flags: DIFlagPrototyped, isOptimized: false, unit: !0, variables: !2)
+!7 = distinct !DISubprogram(name: "f", linkageName: "\01?f@@YAXXZ", scope: !1, file: !1, line: 1, type: !8, isLocal: false, isDefinition: true, scopeLine: 1, flags: DIFlagPrototyped, isOptimized: false, unit: !0, retainedNodes: !2)
 !8 = !DISubroutineType(types: !9)
 !9 = !{null}
 !10 = !DILocation(line: 1, column: 11, scope: !7)