Temporarily Revert "[DebugInfo] Terminate more location-list ranges at the end of blocks"

as it was causing significant compile time regressions.

This reverts commit r359426 while we come up with testcases and additional ideas.

llvm-svn: 360301

4 files changed, 15 insertions, 382 deletions

diff --git a/llvm/test/DebugInfo/COFF/pieces.ll b/llvm/test/DebugInfo/COFF/pieces.ll
index 8fbdce3cbeb..dc5045cc88d 100644
--- a/llvm/test/DebugInfo/COFF/pieces.ll
+++ b/llvm/test/DebugInfo/COFF/pieces.ll
@@ -40,10 +40,9 @@
 ; ASM: # %bb.2:                                 # %for.body.preheader
 ; ASM:         xorl    %edi, %edi
 ; ASM:         xorl    %esi, %esi
-; ASM: [[oy_ox_start:\.Ltmp[0-9]+]]:
 ; ASM:         .p2align        4, 0x90
 ; ASM: .LBB0_3:                                # %for.body
-; ASM:        #DEBUG_VALUE: loop_csr:o <- [DW_OP_LLVM_fragment 0 32] 0
+; ASM: [[oy_ox_start:\.Ltmp[0-9]+]]:
 ; ASM:        #DEBUG_VALUE: loop_csr:o <- [DW_OP_LLVM_fragment 0 32] $edi
 ; ASM:        #DEBUG_VALUE: loop_csr:o <- [DW_OP_LLVM_fragment 32 32] $esi
 ; ASM:        .cv_loc 0 1 13 11               # t.c:13:11
@@ -60,21 +59,13 @@
 ; ASM:         #DEBUG_VALUE: loop_csr:o <- [DW_OP_LLVM_fragment 32 32] $esi
 ; ASM:         cmpl    n(%rip), %eax
 ; ASM:         jl      .LBB0_3
-; ASM: [[loopskip_start:\.Ltmp[0-9]+]]:
-; ASM:         #DEBUG_VALUE: loop_csr:o <- [DW_OP_LLVM_fragment 0 32] 0
-; ASM:         xorl    %esi, %esi
-; ASM:         xorl    %edi, %edi
 ; ASM: [[oy_end:\.Ltmp[0-9]+]]:
 ; ASM:         addl    %edi, %esi
 ; ASM:         movl    %esi, %eax
 
-; XXX FIXME: the debug value line after loopskip_start should be repeated
-; because both fields of 'o' are zero flowing into this block. However, it
-; appears livedebugvalues doesn't account for fragments.
 
 ; ASM-LABEL: pad_right: # @pad_right
 ; ASM:         movq    %rcx, %rax
-; ASM: [[pad_right_tmp:\.Ltmp[0-9]+]]:
 ; ASM:         #DEBUG_VALUE: pad_right:o <- [DW_OP_LLVM_fragment 32 32] $eax
 ; ASM:         retq
 
@@ -82,7 +73,6 @@
 ; ASM-LABEL: pad_left: # @pad_left
 ; ASM:         .cv_loc 2 1 24 3                # t.c:24:3
 ; ASM:         movq    %rcx, %rax
-; ASM: [[pad_left_tmp:\.Ltmp[0-9]+]]:
 ; ASM:         #DEBUG_VALUE: pad_left:o <- [DW_OP_LLVM_fragment 0 32] $eax
 ; ASM:         retq
 
@@ -114,8 +104,8 @@
 ; ASM:        .asciz  "o"
 ; ASM:        .cv_def_range    [[oy_ox_start]] [[ox_start]], "C\021\030\000\000\000\000\000\000\000"
 ; ASM:        .cv_def_range    [[oy_ox_start]] [[oy_start]], "C\021\027\000\000\000\004\000\000\000"
-; ASM:        .cv_def_range    [[ox_start]] [[loopskip_start]], "C\021\030\000\000\000\000\000\000\000"
-; ASM:        .cv_def_range    [[oy_start]] [[loopskip_start]], "C\021\027\000\000\000\004\000\000\000"
+; ASM:        .cv_def_range    [[ox_start]] [[oy_end]], "C\021\030\000\000\000\000\000\000\000"
+; ASM:        .cv_def_range    [[oy_start]] [[oy_end]], "C\021\027\000\000\000\004\000\000\000"
 
 
 ; OBJ-LABEL: GlobalProcIdSym {
@@ -146,7 +136,7 @@
 ; ASM:        .asciz  "pad_right"             # Function name
 ; ASM:        .short  4414                    # Record kind: S_LOCAL
 ; ASM:        .asciz  "o"
-; ASM:        .cv_def_range    [[pad_right_tmp]] [[pad_right_tmp]], "C\021\021\000\000\000\004\000\000\000"
+; ASM:        .cv_def_range    .Ltmp8 .Ltmp8, "C\021\021\000\000\000\004\000\000\000"
 
 ; OBJ-LABEL: GlobalProcIdSym {
 ; OBJ:         Kind: S_GPROC32_ID (0x1147)
@@ -169,7 +159,7 @@
 ; ASM:        .asciz  "pad_left"              # Function name
 ; ASM:        .short  4414                    # Record kind: S_LOCAL
 ; ASM:        .asciz  "o"
-; ASM:        .cv_def_range    [[pad_left_tmp]] [[pad_left_tmp]], "C\021\021\000\000\000\000\000\000\000"
+; ASM:        .cv_def_range    .Ltmp10 .Ltmp10, "C\021\021\000\000\000\000\000\000\000"
 
 ; OBJ-LABEL: GlobalProcIdSym {
 ; OBJ:         Kind: S_GPROC32_ID (0x1147)
diff --git a/llvm/test/DebugInfo/MIR/AArch64/implicit-def-dead-scope.mir b/llvm/test/DebugInfo/MIR/AArch64/implicit-def-dead-scope.mir
index d2a8d4cd322..06db4150684 100644
--- a/llvm/test/DebugInfo/MIR/AArch64/implicit-def-dead-scope.mir
+++ b/llvm/test/DebugInfo/MIR/AArch64/implicit-def-dead-scope.mir
@@ -5,10 +5,8 @@
 #  encountering an IMPLICIT_DEF in its own lexical scope.
 
 # CHECK: .debug_info contents:
-# CHECK:       DW_TAG_formal_parameter
-# CHECK:       DW_AT_location [DW_FORM_sec_offset]
-# CHECK-NEXT:                 DW_OP_lit0, DW_OP_stack_value
-# CHECK-NEXT:  DW_AT_abstract_origin {{.*}} "name"
+# CHECK: DW_TAG_formal_parameter
+# CHECK:   DW_AT_const_value [DW_FORM_udata]   (0)
 --- |
   ; ModuleID = 't.ll'
   source_filename = "t.ll"
@@ -105,7 +103,7 @@
   !15 = distinct !DICompositeType(tag: DW_TAG_class_type, name: "v", file: !5, line: 97, size: 64, elements: !2, identifier: "_ZTS1v")
   !16 = !DISubroutineType(types: !2)
   !17 = !DISubprogram(name: "bv", linkageName: "_ZN1v2bvEv", scope: !15, file: !5, line: 98, type: !16, isLocal: false, isDefinition: false, scopeLine: 98, flags: DIFlagPrototyped, isOptimized: true)
-  !18 = !DILocalVariable(name: "name", arg: 2, scope: !19, file: !5, line: 22, type: !21)
+  !18 = !DILocalVariable(arg: 2, scope: !19, file: !5, line: 22, type: !21)
   !19 = distinct !DISubprogram(name: "m", linkageName: "_ZN1jILi6EN1a1fEE1mEj", scope: !11, file: !5, line: 22, type: !16, isLocal: false, isDefinition: true, scopeLine: 22, flags: DIFlagPrototyped, isOptimized: true, unit: !0, declaration: !20, retainedNodes: !2)
   !20 = !DISubprogram(name: "m", linkageName: "_ZN1jILi6EN1a1fEE1mEj", scope: !11, file: !5, line: 22, type: !16, isLocal: false, isDefinition: false, scopeLine: 22, flags: DIFlagPublic | DIFlagPrototyped, isOptimized: true)
   !21 = !DIDerivedType(tag: DW_TAG_typedef, name: "h", file: !5, line: 10, baseType: !22)
diff --git a/llvm/test/DebugInfo/X86/fission-ranges.ll b/llvm/test/DebugInfo/X86/fission-ranges.ll
index b9a1675d608..1a1dc22870a 100644
--- a/llvm/test/DebugInfo/X86/fission-ranges.ll
+++ b/llvm/test/DebugInfo/X86/fission-ranges.ll
@@ -15,7 +15,6 @@
 ; CHECK-NEXT: DW_AT_GNU_addr_base [DW_FORM_sec_offset]                   (0x00000000)
 
 ; CHECK: .debug_info.dwo contents:
-; CHECK: DW_AT_location [DW_FORM_sec_offset]   ([[P:0x[0-9a-z]*]]
 ; CHECK: DW_AT_location [DW_FORM_sec_offset]   ([[A:0x[0-9a-z]*]]
 ; CHECK: DW_AT_location [DW_FORM_sec_offset]   ([[E:0x[0-9a-z]*]]
 ; CHECK: DW_AT_location [DW_FORM_sec_offset]   ([[B:0x[0-9a-z]*]]
@@ -28,31 +27,24 @@
 ; Don't assume these locations are entirely correct - feel free to update them
 ; if they've changed due to a bugfix, change in register allocation, etc.
 
-; CHECK:      [[P]]:
-; CHECK-NEXT:   Addr idx 1 (w/ length 204): DW_OP_consts +1, DW_OP_stack_value
 ; CHECK:      [[A]]:
 ; CHECK-NEXT:   Addr idx 2 (w/ length 169): DW_OP_consts +0, DW_OP_stack_value
-; CHECK-NEXT:   Addr idx 3 (w/ length 15): DW_OP_reg0 RAX
-; CHECK-NEXT:   Addr idx 4 (w/ length 6): DW_OP_breg7 RSP-8
-; CHECK-NEXT:   Addr idx 5 (w/ length 4): DW_OP_reg0 RAX
+; CHECK-NEXT:   Addr idx 3 (w/ length 25): DW_OP_reg0 RAX
 ; CHECK:      [[E]]:
-; CHECK-NEXT:   Addr idx 6 (w/ length 9): DW_OP_reg0 RAX
-; CHECK-NEXT:   Addr idx 7 (w/ length 98): DW_OP_breg7 RSP-44
+; CHECK-NEXT:   Addr idx 4 (w/ length 19): DW_OP_reg0 RAX
 ; CHECK:      [[B]]:
-; CHECK-NEXT:   Addr idx 8 (w/ length 15): DW_OP_reg0 RAX
-; CHECK-NEXT:   Addr idx 9 (w/ length 66): DW_OP_breg7 RSP-32
+; CHECK-NEXT:   Addr idx 5 (w/ length 17): DW_OP_reg0 RAX
 ; CHECK:      [[D]]:
-; CHECK-NEXT:   Addr idx 10 (w/ length 15): DW_OP_reg0 RAX
-; CHECK-NEXT:   Addr idx 11 (w/ length 42): DW_OP_breg7 RSP-20
+; CHECK-NEXT:   Addr idx 6 (w/ length 17): DW_OP_reg0 RAX
 
 ; Make sure we don't produce any relocations in any .dwo section (though in particular, debug_info.dwo)
 ; HDR-NOT: .rela.{{.*}}.dwo
 
 ; Make sure we have enough stuff in the debug_addr to cover the address indexes
-; (11 is the last index in debug_loc.dwo, making 12 entries of 8 bytes each,
-; 12 * 8 == 96 base 10 == 60 base 16)
+; (6 is the last index in debug_loc.dwo, making 7 entries of 8 bytes each, 7 * 8
+; == 56 base 10 == 38 base 16)
 
-; HDR: .debug_addr 00000060
+; HDR: .debug_addr 00000038
 ; HDR-NOT: .rela.{{.*}}.dwo
 
 ; Check for the existence of a DWARF v5-style range list table in the .debug_rnglists
diff --git a/llvm/test/DebugInfo/X86/live-debug-values-constprop.mir b/llvm/test/DebugInfo/X86/live-debug-values-constprop.mir
deleted file mode 100644
index 086f664e19a..00000000000
--- a/llvm/test/DebugInfo/X86/live-debug-values-constprop.mir
+++ /dev/null
@@ -1,347 +0,0 @@
-# RUN: llc %s -o - -run-pass=livedebugvalues -mtriple=x86_64-unknown-unknown | FileCheck %s --check-prefix=CHECK
-# RUN: llc %s -o - -start-before=livedebugvalues -filetype=obj -mtriple=x86_64-unknown-unknown | llvm-dwarfdump - | FileCheck %s --check-prefix=RANGES
-# Check that livedebugvalues does the right thing when register and constant
-# DBG_VALUEs interact, and that their ranges are correctly terminated by the
-# debug printing backend.
---- |
-  ; All these IR functions are duds, see the MIR below.
-  source_filename = "<stdin>"
-  target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
-  
-  define i32 @foo(i32* %bees, i32* %output) !dbg !4 {
-  entry:
-    br i1 undef, label %bb1, label %bb1
-  bb1:
-    br label %bb3
-  bb2:
-    br label %bb3
-  bb3:
-    ret i32 0
-  }
-
-  define i32 @bar(i32* %bees, i32* %output) !dbg !40 {
-  entry:
-    br i1 undef, label %bb1, label %bb1
-  bb1:
-    br label %bb3
-  bb2:
-    br label %bb3
-  bb3:
-    ret i32 0
-  }
-
-  define i32 @baz(i32* %bees, i32* %output) !dbg !80 {
-  entry:
-    br i1 undef, label %bb1, label %bb1
-  bb1:
-    br label %bb3
-  bb2:
-    br label %bb3
-  bb3:
-    ret i32 0
-  }
-
-  define i32 @qux(i32* %bees, i32* %output) !dbg !120 {
-  entry:
-    br i1 undef, label %bb1, label %bb1
-  bb1:
-    br label %bb3
-  bb2:
-    br label %bb3
-  bb3:
-    ret i32 0
-  }
-
-  ; Function Attrs: nounwind readnone speculatable
-  declare void @llvm.dbg.value(metadata, metadata, metadata)
-  
-  ; Function Attrs: nounwind readnone speculatable
-  declare void @llvm.dbg.declare(metadata, metadata, metadata)
-  
-  ; Function Attrs: nounwind
-  declare void @llvm.stackprotector(i8*, i8**)
-  
-  !llvm.module.flags = !{!0, !100}
-  !llvm.dbg.cu = !{!1}
-  
-  !100 = !{i32 2, !"Dwarf Version", i32 4}
-  !0 = !{i32 2, !"Debug Info Version", i32 3}
-  !1 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus, file: !2, producer: "beards", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug)
-  !2 = !DIFile(filename: "bees.cpp", directory: ".")
-  !3 = !DILocalVariable(name: "flannel", scope: !4, file: !2, line: 1, type: !16)
-  !4 = distinct !DISubprogram(name: "nope", scope: !2, file: !2, line: 1, spFlags: DISPFlagDefinition, unit: !1, retainedNodes: !13, type: !14, isDefinition: true)
-  !5 = !DILocation(line: 0, scope: !4)
-  !6 = !DILocation(line: 1, scope: !4)
-  !7 = !DILocation(line: 2, scope: !4)
-  !8 = !DILocation(line: 4, scope: !4)
-  !9 = !DILocation(line: 5, scope: !4)
-  !10 = !DILocation(line: 6, scope: !4)
-  !11 = !DILocation(line: 7, scope: !4)
-  !12 = !DILocation(line: 8, scope: !4)
-  !13 = !{!3}
-  !14 = !DISubroutineType(types: !15)
-  !15 = !{!16}
-  !16 = !DIBasicType(name: "int", size: 32, align: 32, encoding: DW_ATE_signed)
-  !40 = distinct !DISubprogram(name: "bar", scope: !2, file: !2, line: 1, spFlags: DISPFlagDefinition, unit: !1, retainedNodes: !13, type: !14, isDefinition: true)
-  !41 = !DILocalVariable(name: "towel", scope: !40, file: !2, line: 1, type: !16)
-  !42 = !DILocation(line: 40, scope: !40)
-  !80 = distinct !DISubprogram(name: "baz", scope: !2, file: !2, line: 1, spFlags: DISPFlagDefinition, unit: !1, retainedNodes: !13, type: !14, isDefinition: true)
-  !81 = !DILocalVariable(name: "socks", scope: !80, file: !2, line: 1, type: !16)
-  !82 = !DILocation(line: 40, scope: !80)
-  !120 = distinct !DISubprogram(name: "qux", scope: !2, file: !2, line: 1, spFlags: DISPFlagDefinition, unit: !1, retainedNodes: !13, type: !14, isDefinition: true)
-  !121 = !DILocalVariable(name: "shoes", scope: !120, file: !2, line: 1, type: !16)
-  !122 = !DILocation(line: 40, scope: !120)
-
-...
----
-name:            foo
-alignment:       4
-tracksRegLiveness: true
-registers:       []
-liveins:         
-  - { reg: '$rdi', virtual-reg: '' }
-body:             |
-
-  ; Two DBG_VALUEs for eax merge into bb3, check that livedebugvalues propagates
-  ; the location.
-  ; CHECK-LABEL: name: foo
-  ; CHECK-LABEL: bb.1.bb1
-  ; CHECK:       $eax = MOV32rr
-  ; CHECK-NEXT:  DBG_VALUE $eax
-  ; CHECK-NEXT:  JMP_1 %bb.3
-  ; CHECK-LABEL: bb.2.bb2
-  ; CHECK:       $eax = ADD32ri8
-  ; CHECK-NEXT:  DBG_VALUE $eax
-  ; CHECK-NEXT:  JMP_1 %bb.3
-  ; CHECK-LABEL: bb.3.bb3
-  ; CHECK:       DBG_VALUE $eax
-  ; Test for there being a location-list gap between bb1 and bb2, as the
-  ; variable does not have a location over the ADD32ri. The range should also
-  ; extend over the final bb.
-  ; RANGES-LABEL: DW_TAG_subprogram
-  ; RANGES:       DW_AT_high_pc (0x[[NOPEHIGHPC:[0-9a-f]+]])
-  ; RANGES-LABEL: DW_AT_name ("nope")
-  ; RANGES:       DW_AT_location (0x{{[0-9a-f]+}}
-  ; RANGES-NEXT:   [0x{{[0-9a-f]+}}, 0x[[NOPEADDR:[0-9a-f]+]]): DW_OP_reg0 RAX
-  ; RANGES-NEXT:   [
-  ; RANGES-NOT:    0x[[NOPEADDR]]
-  ; RANGES-SAME:   , 0x[[NOPEHIGHPC]]): DW_OP_reg0 RAX
-
-  bb.0.entry:
-    successors: %bb.1, %bb.2
-    liveins: $rdi
-  
-    $ecx = XOR32rr undef $ecx, undef $ecx, implicit-def $eflags
-    JCC_1 %bb.1, 2, implicit killed $eflags
-    JMP_1 %bb.2
-  
-  bb.1.bb1 (align 4):
-    successors: %bb.3
-    liveins: $ecx, $rdi
-  
-    $eax = MOV32rr killed $ecx, implicit-def $rax
-    DBG_VALUE $eax, $noreg, !3, !DIExpression(), debug-location !8
-    JMP_1 %bb.3
-  
-  bb.2.bb2:
-    successors: %bb.3
-    liveins: $rax
-  
-    $eax = ADD32ri8 $eax, 3, implicit-def dead $eflags, implicit killed $rax, implicit-def $rax
-    DBG_VALUE $eax, $noreg, !3, !DIExpression(), debug-location !8
-    JMP_1 %bb.3
-
-  bb.3.bb3:
-    liveins: $rax
-    RETQ $eax, debug-location !9
-
-...
----
-name:            bar
-alignment:       4
-tracksRegLiveness: true
-registers:       []
-liveins:         
-  - { reg: '$rdi', virtual-reg: '' }
-body:             |
-  ; Two DBG_VALUEs, one for eax, the other for zero, merge into bb3. Check that
-  ; livedebugvalues does not propagate anything.
-  ; the location.
-  ; CHECK-LABEL: name: bar
-  ; CHECK-LABEL: bb.1.bb1
-  ; CHECK:       $eax = MOV32rr
-  ; CHECK-NEXT:  DBG_VALUE 0
-  ; CHECK-NEXT:  JMP_1 %bb.3
-  ; CHECK-LABEL: bb.2.bb2
-  ; CHECK:       $eax = ADD32ri8
-  ; CHECK-NEXT:  DBG_VALUE $eax
-  ; CHECK-NEXT:  JMP_1 %bb.3
-  ; CHECK-LABEL: bb.3.bb3
-  ; CHECK-NOT:   DBG_VALUE
-  ; Test for there being a location-list gap between bb1 and bb2, the variable
-  ; should not have a location over the ADD32ri. The range of the last entry
-  ; should not cover the last block.
-  ; RANGES-LABEL: DW_TAG_subprogram
-  ; RANGES:       DW_AT_high_pc (0x[[BARHIGHPC:[0-9a-f]+]])
-  ; RANGES-LABEL: DW_AT_name ("bar")
-  ; RANGES:       DW_AT_location (0x{{[0-9a-f]+}}
-  ; RANGES-NEXT:   [0x{{[0-9a-f]+}}, 0x[[BARADDR:[0-9a-f]+]]): DW_OP_consts +0, DW_OP_stack_value
-  ; RANGES-NEXT:   [
-  ; RANGES-NOT:    0x[[BARADDR]]
-  ; RANGES-NOT:    0x[[BARHIGHPC]]
-  ; RANGES-SAME:   ): DW_OP_reg0 RAX
-
-  bb.0.entry:
-    successors: %bb.1, %bb.2
-    liveins: $rdi
-  
-    $ecx = XOR32rr undef $ecx, undef $ecx, implicit-def $eflags
-    JCC_1 %bb.1, 2, implicit killed $eflags
-    JMP_1 %bb.2
-  
-  bb.1.bb1 (align 4):
-    successors: %bb.3
-    liveins: $ecx, $rdi
-  
-    $eax = MOV32rr killed $ecx, implicit-def $rax
-    DBG_VALUE 0, $noreg, !41, !DIExpression(), debug-location !42
-    JMP_1 %bb.3
-  
-  bb.2.bb2:
-    successors: %bb.3
-    liveins: $rax
-  
-    $eax = ADD32ri8 $eax, 3, implicit-def dead $eflags, implicit killed $rax, implicit-def $rax
-    DBG_VALUE $eax, $noreg, !41, !DIExpression(), debug-location !42
-    JMP_1 %bb.3
-
-  bb.3.bb3:
-    liveins: $rax
-    RETQ $eax, debug-location !42
-
-...
----
-name:            baz
-alignment:       4
-tracksRegLiveness: true
-registers:       []
-liveins:         
-  - { reg: '$rdi', virtual-reg: '' }
-body:             |
-  ; Two DBG_VALUEs, one for zero, the other for eax, merge into bb3. Check that
-  ; livedebugvalues does not propagate anything.
-  ; the location.
-  ; CHECK-LABEL: name: baz
-  ; CHECK-LABEL: bb.1.bb1
-  ; CHECK:       $eax = MOV32rr
-  ; CHECK-NEXT:  DBG_VALUE $eax
-  ; CHECK-NEXT:  JMP_1 %bb.3
-  ; CHECK-LABEL: bb.2.bb2
-  ; CHECK:       $eax = ADD32ri8
-  ; CHECK-NEXT:  DBG_VALUE 0
-  ; CHECK-NEXT:  JMP_1 %bb.3
-  ; CHECK-LABEL: bb.3.bb3
-  ; CHECK-NOT:   DBG_VALUE
-  ; Test for there being a location-list gap between bb1 and bb2, the variable
-  ; should not have a location over the ADD32ri. The range of the last item
-  ; should not cover the last block.
-  ; RANGES-LABEL: DW_TAG_subprogram
-  ; RANGES:       DW_AT_high_pc (0x[[BAZHIGHPC:[0-9a-f]+]])
-  ; RANGES-LABEL: DW_AT_name ("baz")
-  ; RANGES:       DW_AT_location (0x{{[0-9a-f]+}}
-  ; RANGES-NEXT:   [0x{{[0-9a-f]+}}, 0x[[BAZADDR:[0-9a-f]+]]): DW_OP_reg0 RAX
-  ; RANGES-NEXT:   [
-  ; RANGES-NOT:    0x[[BAZADDR]]
-  ; RANGES-NOT:    0x[[BAZHIGHPC]]
-  ; RANGES-SAME:   ): DW_OP_consts +0, DW_OP_stack_value
-
-  bb.0.entry:
-    successors: %bb.1, %bb.2
-    liveins: $rdi
-  
-    $ecx = XOR32rr undef $ecx, undef $ecx, implicit-def $eflags
-    JCC_1 %bb.1, 2, implicit killed $eflags
-    JMP_1 %bb.2
-  
-  bb.1.bb1 (align 4):
-    successors: %bb.3
-    liveins: $ecx, $rdi
-  
-    $eax = MOV32rr killed $ecx, implicit-def $rax
-    DBG_VALUE $eax, $noreg, !81, !DIExpression(), debug-location !82
-    JMP_1 %bb.3
-  
-  bb.2.bb2:
-    successors: %bb.3
-    liveins: $rax
-  
-    $eax = ADD32ri8 $eax, 3, implicit-def dead $eflags, implicit killed $rax, implicit-def $rax
-    DBG_VALUE 0, $noreg, !81, !DIExpression(), debug-location !82
-    JMP_1 %bb.3
-
-  bb.3.bb3:
-    liveins: $rax
-    RETQ $eax, debug-location !82
-
-...
----
-name:            qux
-alignment:       4
-tracksRegLiveness: true
-registers:       []
-liveins:         
-  - { reg: '$rdi', virtual-reg: '' }
-body:             |
-  ; Two DBG_VALUEs for zero merging into bb3, Check that livedebugvalues does
-  ; propagate the zero into the merging block.
-  ; CHECK-LABEL: name: qux
-  ; CHECK-LABEL: bb.1.bb1
-  ; CHECK:       $eax = MOV32rr
-  ; CHECK-NEXT:  DBG_VALUE 0
-  ; CHECK-NEXT:  JMP_1 %bb.3
-  ; CHECK-LABEL: bb.2.bb2
-  ; CHECK:       $eax = ADD32ri8
-  ; CHECK-NEXT:  DBG_VALUE 0
-  ; CHECK-NEXT:  JMP_1 %bb.3
-  ; CHECK-LABEL: bb.3.bb3
-  ; CHECK:       DBG_VALUE 0
-  ; Test for there being a location-list gap between bb1 and bb2, the variable
-  ; should not have a location over the ADD32ri. The final entry should cover
-  ; the final block.
-  ; RANGES-LABEL: DW_TAG_subprogram
-  ; RANGES:       DW_AT_high_pc (0x[[QUXHIGHPC:[0-9a-f]+]])
-  ; RANGES-LABEL: DW_AT_name ("qux")
-  ; RANGES:       DW_AT_location (0x{{[0-9a-f]+}}
-  ; RANGES-NEXT:   [0x{{[0-9a-f]+}}, 0x[[QUXADDR:[0-9a-f]+]]): DW_OP_consts +0, DW_OP_stack_value
-  ; RANGES-NOT:    0x[[QUXADDR]]
-  ; RANGES-NEXT:   [0x{{[0-9a-f]+}}, 0x[[QUXHIGHPC]]): DW_OP_consts +0, DW_OP_stack_value
-
-  bb.0.entry:
-    successors: %bb.1, %bb.2
-    liveins: $rdi
-  
-    $ecx = XOR32rr undef $ecx, undef $ecx, implicit-def $eflags
-    JCC_1 %bb.1, 2, implicit killed $eflags
-    JMP_1 %bb.2
-  
-  bb.1.bb1 (align 4):
-    successors: %bb.3
-    liveins: $ecx, $rdi
-  
-    $eax = MOV32rr killed $ecx, implicit-def $rax
-    DBG_VALUE 0, $noreg, !121, !DIExpression(), debug-location !122
-    JMP_1 %bb.3
-  
-  bb.2.bb2:
-    successors: %bb.3
-    liveins: $rax
-  
-    $eax = ADD32ri8 $eax, 3, implicit-def dead $eflags, implicit killed $rax, implicit-def $rax
-    DBG_VALUE 0, $noreg, !121, !DIExpression(), debug-location !122
-    JMP_1 %bb.3
-
-  bb.3.bb3:
-    liveins: $rax
-    RETQ $eax, debug-location !122
-
-...