diff options
| -rw-r--r-- | llvm/lib/CodeGen/AsmPrinter/DwarfExpression.cpp | 7 | ||||
| -rw-r--r-- | llvm/lib/CodeGen/TargetInstrInfo.cpp | 21 | ||||
| -rw-r--r-- | llvm/test/DebugInfo/MIR/X86/dbg-call-site-spilled-arg.mir | 177 |
3 files changed, 200 insertions, 5 deletions
diff --git a/llvm/lib/CodeGen/AsmPrinter/DwarfExpression.cpp b/llvm/lib/CodeGen/AsmPrinter/DwarfExpression.cpp index 1c5a244d7c5..96ce3600417 100644 --- a/llvm/lib/CodeGen/AsmPrinter/DwarfExpression.cpp +++ b/llvm/lib/CodeGen/AsmPrinter/DwarfExpression.cpp @@ -246,8 +246,8 @@ bool DwarfExpression::addMachineRegExpression(const TargetRegisterInfo &TRI, // a call site parameter expression and if that expression is just a register // location, emit it with addBReg and offset 0, because we should emit a DWARF // expression representing a value, rather than a location. - if (!isMemoryLocation() && !HasComplexExpression && - (!isParameterValue() || isEntryValue())) { + if (!isMemoryLocation() && !HasComplexExpression && (!isParameterValue() || + isEntryValue())) { for (auto &Reg : DwarfRegs) { if (Reg.DwarfRegNo >= 0) addReg(Reg.DwarfRegNo, Reg.Comment); @@ -436,9 +436,6 @@ void DwarfExpression::addExpression(DIExpressionCursor &&ExprCursor, break; case dwarf::DW_OP_deref: assert(!isRegisterLocation()); - // For more detailed explanation see llvm.org/PR43343. - assert(!isParameterValue() && "Parameter entry values should not be " - "dereferenced due to safety reasons."); if (!isMemoryLocation() && ::isMemoryLocation(ExprCursor)) // Turning this into a memory location description makes the deref // implicit. diff --git a/llvm/lib/CodeGen/TargetInstrInfo.cpp b/llvm/lib/CodeGen/TargetInstrInfo.cpp index 81238307d3f..2b987dabd24 100644 --- a/llvm/lib/CodeGen/TargetInstrInfo.cpp +++ b/llvm/lib/CodeGen/TargetInstrInfo.cpp @@ -1131,6 +1131,27 @@ TargetInstrInfo::describeLoadedValue(const MachineInstr &MI) const { } else if (auto DestSrc = isAddImmediate(MI, Offset)) { Expr = DIExpression::prepend(Expr, DIExpression::ApplyOffset, Offset); return ParamLoadedValue(*DestSrc->Source, Expr); + } else if (MI.hasOneMemOperand()) { + // Only describe memory which provably does not escape the function. As + // described in llvm.org/PR43343, escaped memory may be clobbered by the + // callee (or by another thread). + const auto &TII = MF->getSubtarget().getInstrInfo(); + const MachineFrameInfo &MFI = MF->getFrameInfo(); + const MachineMemOperand *MMO = MI.memoperands()[0]; + const PseudoSourceValue *PSV = MMO->getPseudoValue(); + + // If the address points to "special" memory (e.g. a spill slot), it's + // sufficient to check that it isn't aliased by any high-level IR value. + if (!PSV || PSV->mayAlias(&MFI)) + return None; + + const auto &TRI = MF->getSubtarget().getRegisterInfo(); + const MachineOperand *BaseOp; + if (!TII->getMemOperandWithOffset(MI, BaseOp, Offset, TRI)) + return None; + + Expr = DIExpression::prepend(Expr, DIExpression::DerefAfter, Offset); + return ParamLoadedValue(*BaseOp, Expr); } return None; diff --git a/llvm/test/DebugInfo/MIR/X86/dbg-call-site-spilled-arg.mir b/llvm/test/DebugInfo/MIR/X86/dbg-call-site-spilled-arg.mir new file mode 100644 index 00000000000..26ea062c499 --- /dev/null +++ b/llvm/test/DebugInfo/MIR/X86/dbg-call-site-spilled-arg.mir @@ -0,0 +1,177 @@ +# Check that llvm can describe a call site parameter which resides in a spill slot. +# +# RUN: llc -debug-entry-values -start-after=machineverifier -filetype=obj %s -o - | llvm-dwarfdump - | FileCheck %s +# +# Command: +# $ ~/src/builds/llvm-project-master-RA/bin/clang -g -Xclang -femit-debug-entry-values -O2 -c -o spill.o spill.cc -mllvm -stop-before=machineverifier -o spill.mir +# +# Source: +## extern void callee(int); +## +## #define FORCE_SPILL() \ +## asm volatile("" \ +## : \ +## : \ +## : "rax", "rbx", "rcx", "rdx", "rsi", "rdi", "rbp", "r8", "r9", \ +## "r10", "r11", "r12", "r13", "r14", "r15") +## +## __attribute__((disable_tail_calls)) void caller(int x) { +## FORCE_SPILL(); +## callee(x); +## } + +# CHECK-LABEL: DW_TAG_call_site_parameter +# CHECK-NEXT: DW_AT_location (DW_OP_reg5 RDI) +# CHECK-NEXT: DW_AT_call_value (DW_OP_fbreg -44, DW_OP_deref) + +--- | + ; ModuleID = 'spill.cc' + source_filename = "spill.cc" + target datalayout = "e-m:o-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128" + target triple = "x86_64-apple-macosx10.14.0" + + ; Function Attrs: ssp uwtable + define void @_Z6calleri(i32 %x) local_unnamed_addr #0 !dbg !13 { + entry: + call void @llvm.dbg.value(metadata i32 %x, metadata !15, metadata !DIExpression()), !dbg !16 + call void asm sideeffect "", "~{rax},~{rbx},~{rcx},~{rdx},~{rsi},~{rdi},~{rbp},~{r8},~{r9},~{r10},~{r11},~{r12},~{r13},~{r14},~{r15},~{dirflag},~{fpsr},~{flags}"(), !dbg !17, !srcloc !18 + call void @_Z6calleei(i32 %x), !dbg !19 + ret void, !dbg !20 + } + + declare !dbg !4 void @_Z6calleei(i32) local_unnamed_addr + + ; Function Attrs: nounwind readnone speculatable willreturn + declare void @llvm.dbg.value(metadata, metadata, metadata) + + ; Function Attrs: nounwind + declare void @llvm.stackprotector(i8*, i8**) + + attributes #0 = { "disable-tail-calls"="true" "frame-pointer"="all" } + + !llvm.dbg.cu = !{!0} + !llvm.module.flags = !{!8, !9, !10, !11} + !llvm.ident = !{!12} + + !0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus_14, file: !1, producer: "clang version 10.0.0 (git@github.com:llvm/llvm-project.git 132f768649d8f21d577ee220e5e084904874cb3d)", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !2, retainedTypes: !3, nameTableKind: None) + !1 = !DIFile(filename: "spill.cc", directory: "/Users/vsk/tmp/param-analysis") + !2 = !{} + !3 = !{!4} + !4 = !DISubprogram(name: "callee", linkageName: "_Z6calleei", scope: !1, file: !1, line: 1, type: !5, flags: DIFlagPrototyped, spFlags: DISPFlagOptimized, retainedNodes: !2) + !5 = !DISubroutineType(types: !6) + !6 = !{null, !7} + !7 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed) + !8 = !{i32 2, !"Dwarf Version", i32 4} + !9 = !{i32 2, !"Debug Info Version", i32 3} + !10 = !{i32 1, !"wchar_size", i32 4} + !11 = !{i32 7, !"PIC Level", i32 2} + !12 = !{!"clang version 10.0.0 (git@github.com:llvm/llvm-project.git 132f768649d8f21d577ee220e5e084904874cb3d)"} + !13 = distinct !DISubprogram(name: "caller", linkageName: "_Z6calleri", scope: !1, file: !1, line: 10, type: !5, scopeLine: 10, flags: DIFlagPrototyped | DIFlagAllCallsDescribed, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: !0, retainedNodes: !14) + !14 = !{!15} + !15 = !DILocalVariable(name: "x", arg: 1, scope: !13, file: !1, line: 10, type: !7, flags: DIFlagArgumentNotModified) + !16 = !DILocation(line: 0, scope: !13) + !17 = !DILocation(line: 11, column: 3, scope: !13) + !18 = !{i32 -2147469811} + !19 = !DILocation(line: 12, column: 3, scope: !13) + !20 = !DILocation(line: 13, column: 1, scope: !13) + +... +--- +name: _Z6calleri +alignment: 16 +exposesReturnsTwice: false +legalized: false +regBankSelected: false +selected: false +failedISel: false +tracksRegLiveness: true +hasWinCFI: false +registers: [] +liveins: + - { reg: '$edi', virtual-reg: '' } +frameInfo: + isFrameAddressTaken: false + isReturnAddressTaken: false + hasStackMap: false + hasPatchPoint: false + stackSize: 56 + offsetAdjustment: -56 + maxAlignment: 4 + adjustsStack: true + hasCalls: true + stackProtector: '' + maxCallFrameSize: 0 + cvBytesOfCalleeSavedRegisters: 40 + hasOpaqueSPAdjustment: false + hasVAStart: false + hasMustTailInVarArgFunc: false + localFrameSize: 0 + savePoint: '' + restorePoint: '' +fixedStack: + - { id: 0, type: spill-slot, offset: -56, size: 8, alignment: 8, stack-id: default, + callee-saved-register: '$rbx', callee-saved-restored: true, debug-info-variable: '', + debug-info-expression: '', debug-info-location: '' } + - { id: 1, type: spill-slot, offset: -48, size: 8, alignment: 16, stack-id: default, + callee-saved-register: '$r12', callee-saved-restored: true, debug-info-variable: '', + debug-info-expression: '', debug-info-location: '' } + - { id: 2, type: spill-slot, offset: -40, size: 8, alignment: 8, stack-id: default, + callee-saved-register: '$r13', callee-saved-restored: true, debug-info-variable: '', + debug-info-expression: '', debug-info-location: '' } + - { id: 3, type: spill-slot, offset: -32, size: 8, alignment: 16, stack-id: default, + callee-saved-register: '$r14', callee-saved-restored: true, debug-info-variable: '', + debug-info-expression: '', debug-info-location: '' } + - { id: 4, type: spill-slot, offset: -24, size: 8, alignment: 8, stack-id: default, + callee-saved-register: '$r15', callee-saved-restored: true, debug-info-variable: '', + debug-info-expression: '', debug-info-location: '' } + - { id: 5, type: spill-slot, offset: -16, size: 8, alignment: 16, stack-id: default, + callee-saved-register: '', callee-saved-restored: true, debug-info-variable: '', + debug-info-expression: '', debug-info-location: '' } +stack: + - { id: 0, name: '', type: spill-slot, offset: -60, size: 4, alignment: 4, + stack-id: default, callee-saved-register: '', callee-saved-restored: true, + debug-info-variable: '', debug-info-expression: '', debug-info-location: '' } +callSites: + - { bb: 0, offset: 23, fwdArgRegs: + - { arg: 0, reg: '$edi' } } +constants: [] +machineFunctionInfo: {} +body: | + bb.0.entry: + liveins: $edi, $r15, $r14, $r13, $r12, $rbx + + DBG_VALUE $edi, $noreg, !15, !DIExpression(), debug-location !16 + frame-setup PUSH64r killed $rbp, implicit-def $rsp, implicit $rsp + CFI_INSTRUCTION def_cfa_offset 16 + CFI_INSTRUCTION offset $rbp, -16 + $rbp = frame-setup MOV64rr $rsp + CFI_INSTRUCTION def_cfa_register $rbp + frame-setup PUSH64r killed $r15, implicit-def $rsp, implicit $rsp + frame-setup PUSH64r killed $r14, implicit-def $rsp, implicit $rsp + frame-setup PUSH64r killed $r13, implicit-def $rsp, implicit $rsp + frame-setup PUSH64r killed $r12, implicit-def $rsp, implicit $rsp + frame-setup PUSH64r killed $rbx, implicit-def $rsp, implicit $rsp + frame-setup PUSH64r undef $rax, implicit-def $rsp, implicit $rsp + CFI_INSTRUCTION offset $rbx, -56 + CFI_INSTRUCTION offset $r12, -48 + CFI_INSTRUCTION offset $r13, -40 + CFI_INSTRUCTION offset $r14, -32 + CFI_INSTRUCTION offset $r15, -24 + MOV32mr $rbp, 1, $noreg, -44, $noreg, $edi :: (store 4 into %stack.0) + DBG_VALUE $rbp, 0, !15, !DIExpression(DW_OP_constu, 44, DW_OP_minus), debug-location !16 + INLINEASM &"", 1, 12, implicit-def dead early-clobber $rax, 12, implicit-def dead early-clobber $rbx, 12, implicit-def dead early-clobber $rcx, 12, implicit-def dead early-clobber $rdx, 12, implicit-def dead early-clobber $rsi, 12, implicit-def dead early-clobber $rdi, 12, implicit-def early-clobber $rbp, 12, implicit-def dead early-clobber $r8, 12, implicit-def dead early-clobber $r9, 12, implicit-def dead early-clobber $r10, 12, implicit-def dead early-clobber $r11, 12, implicit-def dead early-clobber $r12, 12, implicit-def dead early-clobber $r13, 12, implicit-def dead early-clobber $r14, 12, implicit-def dead early-clobber $r15, 12, implicit-def dead early-clobber $df, 12, implicit-def early-clobber $fpsw, 12, implicit-def dead early-clobber $eflags, !18, debug-location !17 + DBG_VALUE $edi, $noreg, !15, !DIExpression(DW_OP_LLVM_entry_value, 1), debug-location !16 + $edi = MOV32rm $rbp, 1, $noreg, -44, $noreg :: (load 4 from %stack.0) + DBG_VALUE $edi, $noreg, !15, !DIExpression(), debug-location !16 + CALL64pcrel32 @_Z6calleei, csr_64, implicit $rsp, implicit $ssp, implicit $edi, implicit-def $rsp, implicit-def $ssp, debug-location !19 + DBG_VALUE $edi, $noreg, !15, !DIExpression(DW_OP_LLVM_entry_value, 1), debug-location !16 + $rsp = frame-destroy ADD64ri8 $rsp, 8, implicit-def dead $eflags, debug-location !20 + $rbx = frame-destroy POP64r implicit-def $rsp, implicit $rsp, debug-location !20 + $r12 = frame-destroy POP64r implicit-def $rsp, implicit $rsp, debug-location !20 + $r13 = frame-destroy POP64r implicit-def $rsp, implicit $rsp, debug-location !20 + $r14 = frame-destroy POP64r implicit-def $rsp, implicit $rsp, debug-location !20 + $r15 = frame-destroy POP64r implicit-def $rsp, implicit $rsp, debug-location !20 + $rbp = frame-destroy POP64r implicit-def $rsp, implicit $rsp, debug-location !20 + RETQ debug-location !20 + +... |
