Consider regmasks when computing register-based DBG_VALUE live ranges
Now register parameters that aren't saved to the stack or CSRs are
considered dead after the first call. Previously the debugger would show
whatever was in the register.
Fixes PR26589
Reviewers: aprantl
Differential Revision: http://reviews.llvm.org/D17211
llvm-svn: 264429
diff --git a/llvm/test/DebugInfo/MIR/X86/live-debug-values.mir b/llvm/test/DebugInfo/MIR/X86/live-debug-values.mir
index 80f3952..3c72a86 100644
--- a/llvm/test/DebugInfo/MIR/X86/live-debug-values.mir
+++ b/llvm/test/DebugInfo/MIR/X86/live-debug-values.mir
@@ -33,8 +33,7 @@
# DBG_VALUE for variable "n" is extended into BB#5 from its predecessors BB#3
# and BB#4.
# CHECK: bb.5.if.end.7:
-# CHECK: DBG_VALUE debug-use %rsi, debug-use _, !13, !20, debug-location !22
-# CHECK-NEXT: DBG_VALUE debug-use %ebx, debug-use _, !14, !20, debug-location !33
+# CHECK: DBG_VALUE debug-use %ebx, debug-use _, !14, !20, debug-location !33
--- |
diff --git a/llvm/test/DebugInfo/X86/array.ll b/llvm/test/DebugInfo/X86/array.ll
index 4ffe0a7..0714950 100644
--- a/llvm/test/DebugInfo/X86/array.ll
+++ b/llvm/test/DebugInfo/X86/array.ll
@@ -16,9 +16,9 @@
; Test that we only emit register-indirect locations for the array array.
; rdar://problem/14874886
;
-; CHECK: ##DEBUG_VALUE: main:array <- [%R{{.*}}+0]
-; CHECK: ##DEBUG_VALUE: main:array <- [%R{{.*}}+0]
-; CHECK: ##DEBUG_VALUE: main:array <- [%R{{.*}}+0]
+; FIXME: If we described this location as RSP-relative instead of RDI-relative
+; the live range would be larger.
+; CHECK: ##DEBUG_VALUE: main:array <- [%RDI+0]
; CHECK-NOT: ##DEBUG_VALUE: main:array <- %R{{.*}}
target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128"
target triple = "x86_64-apple-macosx10.9.0"
diff --git a/llvm/test/DebugInfo/X86/bbjoin.ll b/llvm/test/DebugInfo/X86/bbjoin.ll
index fea7491..7bf2a30 100644
--- a/llvm/test/DebugInfo/X86/bbjoin.ll
+++ b/llvm/test/DebugInfo/X86/bbjoin.ll
@@ -14,7 +14,7 @@
; CHECK: DBG_VALUE 23, 0, ![[X]],
; CHECK: DBG_VALUE debug-use %rdi, debug-use _, ![[X]]
; CHECK: bb.1.if.then:
-; CHECK: DBG_VALUE debug-use %rdi, debug-use _, ![[X]],
+; CHECK: DBG_VALUE 43, 0, ![[X]],
; CHECK: bb.2.if.end:
; CHECK-NOT: DBG_VALUE 23, 0, ![[X]],
; CHECK: RETQ %eax
diff --git a/llvm/test/DebugInfo/X86/dbg-value-regmask-clobber.ll b/llvm/test/DebugInfo/X86/dbg-value-regmask-clobber.ll
new file mode 100644
index 0000000..d868e85
--- /dev/null
+++ b/llvm/test/DebugInfo/X86/dbg-value-regmask-clobber.ll
@@ -0,0 +1,117 @@
+; RUN: llc < %s | FileCheck %s --check-prefix=ASM
+; RUN: llc < %s -filetype=obj | llvm-dwarfdump - | FileCheck %s --check-prefix=DWARF
+
+; Values in registers should be clobbered by calls, which use a regmask instead
+; of individual register def operands.
+
+; ASM: main: # @main
+; ASM: #DEBUG_VALUE: main:argc <- %ECX
+; ASM: movl $1, x(%rip)
+; ASM: callq clobber
+; ASM-NEXT: [[argc_range_end:.Ltmp[0-9]+]]:
+; Previously LiveDebugValues would claim argc was still in ECX after the call.
+; ASM-NOT: #DEBUG_VALUE: main:argc
+
+; argc is the first debug location.
+; ASM: .Ldebug_loc1:
+; ASM-NEXT: .quad .Lfunc_begin0-.Lfunc_begin0
+; ASM-NEXT: .quad [[argc_range_end]]-.Lfunc_begin0
+; ASM-NEXT: .short 3 # Loc expr size
+; ASM-NEXT: .byte 82 # super-register DW_OP_reg2
+; ASM-NEXT: .byte 147 # DW_OP_piece
+; ASM-NEXT: .byte 4 # 4
+
+; argc is the first formal parameter.
+; DWARF: .debug_info contents:
+; DWARF: DW_TAG_formal_parameter
+; DWARF-NEXT: DW_AT_location [DW_FORM_sec_offset] ([[argc_loc_offset:0x.*]])
+; DWARF-NEXT: DW_AT_name [DW_FORM_strp] {{.*}} "argc"
+
+; DWARF: .debug_loc contents:
+; DWARF: [[argc_loc_offset]]: Beginning address offset: 0x0000000000000000
+; DWARF-NEXT: Ending address offset: 0x0000000000000013
+; DWARF-NEXT: Location description: 52 93 04
+
+; ModuleID = 't.cpp'
+target datalayout = "e-m:w-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-pc-windows-msvc18.0.0"
+
+@x = common global i32 0, align 4
+
+; Function Attrs: nounwind uwtable
+define i32 @main(i32 %argc, i8** nocapture readnone %argv) #0 !dbg !4 {
+entry:
+ tail call void @llvm.dbg.value(metadata i8** %argv, i64 0, metadata !12, metadata !21), !dbg !22
+ tail call void @llvm.dbg.value(metadata i32 %argc, i64 0, metadata !13, metadata !21), !dbg !23
+ store volatile i32 1, i32* @x, align 4, !dbg !24, !tbaa !25
+ tail call void @clobber() #3, !dbg !29
+ store volatile i32 2, i32* @x, align 4, !dbg !30, !tbaa !25
+ %0 = load volatile i32, i32* @x, align 4, !dbg !31, !tbaa !25
+ %tobool = icmp eq i32 %0, 0, !dbg !31
+ br i1 %tobool, label %if.else, label %if.then, !dbg !33
+
+if.then: ; preds = %entry
+ store volatile i32 3, i32* @x, align 4, !dbg !34, !tbaa !25
+ br label %if.end, !dbg !36
+
+if.else: ; preds = %entry
+ store volatile i32 4, i32* @x, align 4, !dbg !37, !tbaa !25
+ br label %if.end
+
+if.end: ; preds = %if.else, %if.then
+ ret i32 0, !dbg !39
+}
+
+declare void @clobber()
+
+; Function Attrs: nounwind readnone
+declare void @llvm.dbg.value(metadata, i64, metadata, metadata) #2
+
+attributes #0 = { nounwind uwtable }
+attributes #2 = { nounwind readnone }
+attributes #3 = { nounwind }
+
+!llvm.dbg.cu = !{!0}
+!llvm.module.flags = !{!17, !18, !19}
+!llvm.ident = !{!20}
+
+!0 = distinct !DICompileUnit(language: DW_LANG_C99, file: !1, producer: "clang version 3.9.0 (trunk 260617) (llvm/trunk 260619)", isOptimized: true, runtimeVersion: 0, emissionKind: 1, enums: !2, subprograms: !3, globals: !14)
+!1 = !DIFile(filename: "t.cpp", directory: "D:\5Csrc\5Cllvm\5Cbuild")
+!2 = !{}
+!3 = !{!4}
+!4 = distinct !DISubprogram(name: "main", scope: !1, file: !1, line: 4, type: !5, isLocal: false, isDefinition: true, scopeLine: 4, flags: DIFlagPrototyped, isOptimized: true, variables: !11)
+!5 = !DISubroutineType(types: !6)
+!6 = !{!7, !7, !8}
+!7 = !DIBasicType(name: "int", size: 32, align: 32, encoding: DW_ATE_signed)
+!8 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !9, size: 64, align: 64)
+!9 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !10, size: 64, align: 64)
+!10 = !DIBasicType(name: "char", size: 8, align: 8, encoding: DW_ATE_signed_char)
+!11 = !{!12, !13}
+!12 = !DILocalVariable(name: "argv", arg: 2, scope: !4, file: !1, line: 4, type: !8)
+!13 = !DILocalVariable(name: "argc", arg: 1, scope: !4, file: !1, line: 4, type: !7)
+!14 = !{!15}
+!15 = !DIGlobalVariable(name: "x", scope: !0, file: !1, line: 1, type: !16, isLocal: false, isDefinition: true, variable: i32* @x)
+!16 = !DIDerivedType(tag: DW_TAG_volatile_type, baseType: !7)
+!17 = !{i32 2, !"Dwarf Version", i32 4}
+!18 = !{i32 2, !"Debug Info Version", i32 3}
+!19 = !{i32 1, !"PIC Level", i32 2}
+!20 = !{!"clang version 3.9.0 (trunk 260617) (llvm/trunk 260619)"}
+!21 = !DIExpression()
+!22 = !DILocation(line: 4, column: 27, scope: !4)
+!23 = !DILocation(line: 4, column: 14, scope: !4)
+!24 = !DILocation(line: 5, column: 5, scope: !4)
+!25 = !{!26, !26, i64 0}
+!26 = !{!"int", !27, i64 0}
+!27 = !{!"omnipotent char", !28, i64 0}
+!28 = !{!"Simple C/C++ TBAA"}
+!29 = !DILocation(line: 6, column: 3, scope: !4)
+!30 = !DILocation(line: 7, column: 5, scope: !4)
+!31 = !DILocation(line: 8, column: 7, scope: !32)
+!32 = distinct !DILexicalBlock(scope: !4, file: !1, line: 8, column: 7)
+!33 = !DILocation(line: 8, column: 7, scope: !4)
+!34 = !DILocation(line: 9, column: 7, scope: !35)
+!35 = distinct !DILexicalBlock(scope: !32, file: !1, line: 8, column: 10)
+!36 = !DILocation(line: 10, column: 3, scope: !35)
+!37 = !DILocation(line: 11, column: 7, scope: !38)
+!38 = distinct !DILexicalBlock(scope: !32, file: !1, line: 10, column: 10)
+!39 = !DILocation(line: 13, column: 1, scope: !4)
diff --git a/llvm/test/DebugInfo/X86/debug-loc-asan.ll b/llvm/test/DebugInfo/X86/debug-loc-asan.ll
index 2e01355..f1bb298 100644
--- a/llvm/test/DebugInfo/X86/debug-loc-asan.ll
+++ b/llvm/test/DebugInfo/X86/debug-loc-asan.ll
@@ -15,8 +15,12 @@
; CHECK: #DEBUG_VALUE: bar:y <- [%RDI+0]
; CHECK: movq %rdi, [[OFFSET:[0-9]+]](%rsp)
; CHECK-NEXT: [[START_LABEL:.Ltmp[0-9]+]]
+; CHECK-NEXT: #DEBUG_VALUE: bar:y <- [complex expression]
; This location should be valid until the end of the function.
+; CHECK: movq %rbp, %rsp
+; CHECK-NEXT: [[END_LABEL:.Ltmp[0-9]+]]:
+
; CHECK: .Ldebug_loc{{[0-9]+}}:
; We expect two location ranges for the variable.
@@ -27,7 +31,7 @@
; Then it's addressed via %rsp:
; CHECK: .quad [[START_LABEL]]-.Lfunc_begin0
-; CHECK-NEXT: .Lfunc_end0-.Lfunc_begin0
+; CHECK-NEXT: .quad [[END_LABEL]]-.Lfunc_begin0
; CHECK: DW_OP_breg7
; CHECK-NEXT: [[OFFSET]]
; CHECK: DW_OP_deref
diff --git a/llvm/test/DebugInfo/X86/live-debug-values.ll b/llvm/test/DebugInfo/X86/live-debug-values.ll
index 615d498..cdd83f7 100644
--- a/llvm/test/DebugInfo/X86/live-debug-values.ll
+++ b/llvm/test/DebugInfo/X86/live-debug-values.ll
@@ -31,7 +31,9 @@
; and BB#4.
; CHECK: .LBB0_5:
; CHECK-NEXT: #DEBUG_VALUE: main:n <- %EBX
-; CHECK-NEXT: #DEBUG_VALUE: main:argv <- %RSI
+; Other register values have been clobbered.
+; CHECK-NOT: #DEBUG_VALUE:
+; CHECK: movl %ecx, m(%rip)
; ModuleID = 'LiveDebugValues.c'
target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
diff --git a/llvm/test/DebugInfo/X86/pr19307.ll b/llvm/test/DebugInfo/X86/pr19307.ll
index 39a8007..66fa27d 100644
--- a/llvm/test/DebugInfo/X86/pr19307.ll
+++ b/llvm/test/DebugInfo/X86/pr19307.ll
@@ -14,7 +14,7 @@
; Location of "range" string is spilled from %rdx to stack and is
; addressed via %rbp.
; CHECK: movq %rdx, {{[-0-9]+}}(%rbp)
-; CHECK-NEXT: [[START_LABEL:.Ltmp[0-9]+]]
+; CHECK-NEXT: [[START_LABEL:.Ltmp[0-9]+]]:
; This location should be valid until the end of the function.
; Verify that we have proper range in debug_loc section: