Remove the obsolete offset parameter from @llvm.dbg.value

There is no situation where this rarely-used argument cannot be
substituted with a DIExpression and removing it allows us to simplify
the DWARF backend. Note that this patch does not yet remove any of
the newly dead code.

rdar://problem/33580047
Differential Revision: https://reviews.llvm.org/D35951

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@309426 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 32 insertions, 0 deletions

diff --git a/test/Bitcode/upgrade-dbg-value.ll b/test/Bitcode/upgrade-dbg-value.ll
new file mode 100644
index 00000000000..5b6ffb6d3e8
--- /dev/null
+++ b/test/Bitcode/upgrade-dbg-value.ll
@@ -0,0 +1,32 @@
+; Test upgrade of dbg.dvalue intrinsics with offsets.
+;
+; RUN: llvm-dis < %s.bc | FileCheck %s
+; RUN: verify-uselistorder < %s.bc
+
+define void @f() !dbg !3 {
+entry:
+  ; CHECK-NOT: call void @llvm.dbg.value
+  ; CHECK: call void @llvm.dbg.value(metadata i32 42, metadata !8, metadata !9), !dbg !10
+  call void @llvm.dbg.value(metadata i32 42, i64 0, metadata !8, metadata !9), !dbg !10
+  ; CHECK-NOT: call void @llvm.dbg.value
+  call void @llvm.dbg.value(metadata i32 0, i64 1, metadata !8, metadata !9), !dbg !10
+  ret void
+}
+
+; CHECK: declare void @llvm.dbg.value(metadata, metadata, metadata)
+declare void @llvm.dbg.value(metadata, i64, metadata, metadata)
+
+!llvm.dbg.cu = !{!0}
+!llvm.module.flags = !{!2}
+
+!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)
+!4 = !DISubroutineType(types: !5)
+!5 = !{!6}
+!6 = !DIBasicType(name: "int", size: 32, align: 32, encoding: DW_ATE_signed)
+!7 = !{!8}
+!8 = !DILocalVariable(name: "i", scope: !3, file: !1, line: 2, type: !6)
+!9 = !DIExpression()
+!10 = !DILocation(line: 2, scope: !3)
diff --git a/test/Bitcode/upgrade-dbg-value.ll.bc b/test/Bitcode/upgrade-dbg-value.ll.bc
new file mode 100644
index 00000000000..574a8e45316
--- /dev/null
+++ b/test/Bitcode/upgrade-dbg-value.ll.bc