llvm/test/DebugInfo/X86/live-debug-vars-intervals.mir

# These tests check that DBG_VALUE intervals are correctly coalesced (or not) in
# LiveDebugVariables.
# NOTE: We do not currently handle partially overlapping fragments in LDV.
#
# The IR in this file has been modified by hand, generated from this source:
# void escape(int *);
# extern int global;
# void f(int x) {
#   escape(&x);
#   x = 1;
#   global = x;
#   x = 2;
#   escape(&x);
# }

# RUN: llc %s -start-before=machine-scheduler -stop-after=virtregrewriter -o - \
# RUN:     | FileCheck %s --implicit-check-not=DBG_VALUE

# Verify that DBG_VALUEs with same { Variable, Fragment } but different DIExpressions
# are not coalesced.
#
# DV1 %0 "x" (deref) --+-- Do not coalesce these because DV2 refers to the same bits.
# DV2 %0 "x" ()        |
# DV3 %0 "x" (deref) --+
#
# CHECK: name: f1
# CHECK: DBG_VALUE %stack.0.x.addr, $noreg, ![[VAR:[0-9]+]], !DIExpression(DW_OP_deref)
# CHECK: DBG_VALUE %stack.0.x.addr, $noreg, ![[VAR]],        !DIExpression()
# CHECK: DBG_VALUE %stack.0.x.addr, $noreg, ![[VAR]],        !DIExpression(DW_OP_deref)

# Verify that DBG_VALUEs with same { Variable, Fragment } and { Location, DIExpression } are
# coalesced if there are no intervening DBG_VALUEs with the same { Variable, Fragment }.
#
# DV1 %0 "x" (fragment 00 16) --+-- Coalesce these because DV2 refers to different bits.
# DV2 %0 "x" (fragment 16 16)   |
# DV3 %0 "x" (fragment 00 16) --+
#
# CHECK: name: f2
# CHECK: DBG_VALUE %stack.0.x.addr, $noreg, ![[VAR:[0-9]+]], !DIExpression(DW_OP_deref, DW_OP_LLVM_fragment, 0, 16)
# CHECK: DBG_VALUE %stack.0.x.addr, $noreg, ![[VAR]],        !DIExpression(DW_OP_LLVM_fragment, 16, 16)

--- |
  target triple = "x86_64-unknown-linux-gnu"

  @global = external global i32, align 4
  declare void @llvm.dbg.value(metadata, metadata, metadata)
  declare void @escape(i32*)

  define void @f1(i32 %x) !dbg !6 {
  entry:
    %x.addr = alloca i32, align 4
    store i32 %x, i32* %x.addr, align 4
    call void @llvm.dbg.value(metadata i32* %x.addr, metadata !11, metadata !DIExpression(DW_OP_deref)), !dbg !12
    call void @escape(i32* %x.addr), !dbg !12
    call void @llvm.dbg.value(metadata i32* %x.addr, metadata !11, metadata !DIExpression()), !dbg !12
    store i32 1, i32* @global, align 4, !dbg !12
    call void @llvm.dbg.value(metadata i32* %x.addr, metadata !11, metadata !DIExpression(DW_OP_deref)), !dbg !12
    store i32 2, i32* %x.addr, align 4, !dbg !12
    call void @escape(i32* %x.addr), !dbg !12
    ret void, !dbg !12
  }

  define void @f2(i32 %x) !dbg !13 {
  entry:
    %x.addr = alloca i32, align 4
    store i32 %x, i32* %x.addr, align 4
    call void @llvm.dbg.value(metadata i32* %x.addr, metadata !14, metadata !DIExpression(DW_OP_deref, DW_OP_LLVM_fragment, 0, 16)), !dbg !15
    call void @escape(i32* %x.addr)
    call void @llvm.dbg.value(metadata i32* %x.addr, metadata !14, metadata !DIExpression(DW_OP_LLVM_fragment, 16, 16)), !dbg !15
    store i32 1, i32* @global, align 4
    call void @llvm.dbg.value(metadata i32* %x.addr, metadata !14, metadata !DIExpression(DW_OP_deref, DW_OP_LLVM_fragment, 0, 16)), !dbg !15
    store i32 2, i32* %x.addr, align 4
    call void @escape(i32* %x.addr)
    ret void
  }

  !llvm.dbg.cu = !{!0}
  !llvm.module.flags = !{!3, !4}
  !llvm.ident = !{!5}

  !0 = distinct !DICompileUnit(language: DW_LANG_C99, file: !1, producer: "clang version 11.0.0 ", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !2)
  !1 = !DIFile(filename: "test.c", directory: "")
  !2 = !{}
  !3 = !{i32 2, !"Dwarf Version", i32 4}
  !4 = !{i32 2, !"Debug Info Version", i32 3}
  !5 = !{!"clang version 11.0.0 "}
  !6 = distinct !DISubprogram(name: "f1", scope: !1, file: !1, line: 3, type: !7, scopeLine: 3, flags: DIFlagPrototyped, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: !0, retainedNodes: !10)
  !7 = !DISubroutineType(types: !8)
  !8 = !{null, !9}
  !9 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
  !10 = !{!11}
  !11 = !DILocalVariable(name: "x", arg: 1, scope: !6, file: !1, line: 3, type: !9)
  !12 = !DILocation(line: 3, column: 12, scope: !6)
  !13 = distinct !DISubprogram(name: "f2", scope: !1, file: !1, line: 20, type: !7, scopeLine: 20, flags: DIFlagPrototyped, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: !0, retainedNodes: !10)
  !14 = !DILocalVariable(name: "x", arg: 1, scope: !13, file: !1, line: 21, type: !9)
  !15 = !DILocation(line: 23, column: 12, scope: !13)

...
---
name:            f1
tracksRegLiveness: true
stack:
  - { id: 0, name: x.addr, type: default, offset: 0, size: 4, alignment: 4,
      stack-id: default, callee-saved-register: '', callee-saved-restored: true,
      debug-info-variable: '', debug-info-expression: '', debug-info-location: '' }
body:             |
  bb.0.entry:
    liveins: $edi
    %0:gr32 = COPY $edi
    MOV32mr %stack.0.x.addr, 1, $noreg, 0, $noreg, %0 :: (store 4 into %ir.x.addr)
    DBG_VALUE %stack.0.x.addr, $noreg, !11, !DIExpression(DW_OP_deref), debug-location !12
    ADJCALLSTACKDOWN64 0, 0, 0, implicit-def dead $rsp, implicit-def dead $eflags, implicit-def dead $ssp, implicit $rsp, implicit $ssp, debug-location !12
    %1:gr64 = LEA64r %stack.0.x.addr, 1, $noreg, 0, $noreg
    $rdi = COPY %1, debug-location !12
    CALL64pcrel32 @escape, csr_64, implicit $rsp, implicit $ssp, implicit $rdi, implicit-def $rsp, implicit-def $ssp, debug-location !12
    ADJCALLSTACKUP64 0, 0, implicit-def dead $rsp, implicit-def dead $eflags, implicit-def dead $ssp, implicit $rsp, implicit $ssp, debug-location !12
    DBG_VALUE %stack.0.x.addr, $noreg, !11, !DIExpression(), debug-location !12
    MOV32mi $rip, 1, $noreg, @global, $noreg, 1, debug-location !12 :: (store 4 into @global)
    DBG_VALUE %stack.0.x.addr, $noreg, !11, !DIExpression(DW_OP_deref), debug-location !12
    MOV32mi %stack.0.x.addr, 1, $noreg, 0, $noreg, 2, debug-location !12 :: (store 4 into %ir.x.addr)
    ADJCALLSTACKDOWN64 0, 0, 0, implicit-def dead $rsp, implicit-def dead $eflags, implicit-def dead $ssp, implicit $rsp, implicit $ssp, debug-location !12
    $rdi = COPY %1, debug-location !12
    CALL64pcrel32 @escape, csr_64, implicit $rsp, implicit $ssp, implicit $rdi, implicit-def $rsp, implicit-def $ssp, debug-location !12
    ADJCALLSTACKUP64 0, 0, implicit-def dead $rsp, implicit-def dead $eflags, implicit-def dead $ssp, implicit $rsp, implicit $ssp, debug-location !12
    RET 0, debug-location !12
...
---
name:            f2
tracksRegLiveness: true
stack:
  - { id: 0, name: x.addr, type: default, offset: 0, size: 4, alignment: 4,
      stack-id: default, callee-saved-register: '', callee-saved-restored: true,
      debug-info-variable: '', debug-info-expression: '', debug-info-location: '' }
body:             |
  bb.0.entry:
    liveins: $edi
    %0:gr32 = COPY $edi
    MOV32mr %stack.0.x.addr, 1, $noreg, 0, $noreg, %0 :: (store 4 into %ir.x.addr)
    DBG_VALUE %stack.0.x.addr, $noreg, !14, !DIExpression(DW_OP_deref, DW_OP_LLVM_fragment, 0, 16), debug-location !15
    ADJCALLSTACKDOWN64 0, 0, 0, implicit-def dead $rsp, implicit-def dead $eflags, implicit-def dead $ssp, implicit $rsp, implicit $ssp
    %1:gr64 = LEA64r %stack.0.x.addr, 1, $noreg, 0, $noreg
    $rdi = COPY %1
    CALL64pcrel32 @escape, csr_64, implicit $rsp, implicit $ssp, implicit $rdi, implicit-def $rsp, implicit-def $ssp
    ADJCALLSTACKUP64 0, 0, implicit-def dead $rsp, implicit-def dead $eflags, implicit-def dead $ssp, implicit $rsp, implicit $ssp
    DBG_VALUE %stack.0.x.addr, $noreg, !14, !DIExpression(DW_OP_LLVM_fragment, 16, 16), debug-location !15
    MOV32mi $rip, 1, $noreg, @global, $noreg, 1 :: (store 4 into @global)
    DBG_VALUE %stack.0.x.addr, $noreg, !14, !DIExpression(DW_OP_deref, DW_OP_LLVM_fragment, 0, 16), debug-location !15
    MOV32mi %stack.0.x.addr, 1, $noreg, 0, $noreg, 2 :: (store 4 into %ir.x.addr)
    ADJCALLSTACKDOWN64 0, 0, 0, implicit-def dead $rsp, implicit-def dead $eflags, implicit-def dead $ssp, implicit $rsp, implicit $ssp
    $rdi = COPY %1
    CALL64pcrel32 @escape, csr_64, implicit $rsp, implicit $ssp, implicit $rdi, implicit-def $rsp, implicit-def $ssp
    ADJCALLSTACKUP64 0, 0, implicit-def dead $rsp, implicit-def dead $eflags, implicit-def dead $ssp, implicit $rsp, implicit $ssp
    RET 0
...