#include "llvm/IR/DebugInfo.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/raw_ostream.h"
+#include "llvm/Target/TargetLowering.h"
#include "llvm/Target/TargetRegisterInfo.h"
+#include "llvm/Target/TargetSubtargetInfo.h"
#include <algorithm>
#include <map>
using namespace llvm;
clobberRegisterUses(RegVars, I, HistMap, ClobberingInstr);
}
-// \brief Collect all registers clobbered by @MI and apply the functor
-// @Func to their RegNo.
-// @Func should be a functor with a void(unsigned) signature. We're
-// not using std::function here for performance reasons. It has a
-// small but measurable impact. By using a functor instead of a
-// std::set& here, we can avoid the overhead of constructing
-// temporaries in calculateDbgValueHistory, which has a significant
-// performance impact.
-template<typename Callable>
-static void applyToClobberedRegisters(const MachineInstr &MI,
- const TargetRegisterInfo *TRI,
- Callable Func) {
- for (const MachineOperand &MO : MI.operands()) {
- if (!MO.isReg() || !MO.isDef() || !MO.getReg())
- continue;
- for (MCRegAliasIterator AI(MO.getReg(), TRI, true); AI.isValid(); ++AI)
- Func(*AI);
- }
-}
-
// \brief Returns the first instruction in @MBB which corresponds to
// the function epilogue, or nullptr if @MBB doesn't contain an epilogue.
static const MachineInstr *getFirstEpilogueInst(const MachineBasicBlock &MBB) {
auto FirstEpilogueInst = getFirstEpilogueInst(MBB);
for (const auto &MI : MBB) {
+ // Avoid looking at prologue or epilogue instructions.
if (&MI == FirstEpilogueInst)
break;
- if (!MI.getFlag(MachineInstr::FrameSetup))
- applyToClobberedRegisters(MI, TRI, [&](unsigned r) { Regs.set(r); });
+ if (MI.getFlag(MachineInstr::FrameSetup))
+ continue;
+
+ // Look for register defs and register masks. Register masks are
+ // typically on calls and they clobber everything not in the mask.
+ for (const MachineOperand &MO : MI.operands()) {
+ if (MO.isReg() && MO.isDef() && MO.getReg()) {
+ for (MCRegAliasIterator AI(MO.getReg(), TRI, true); AI.isValid();
+ ++AI)
+ Regs.set(*AI);
+ } else if (MO.isRegMask()) {
+ Regs.setBitsNotInMask(MO.getRegMask());
+ }
+ }
}
}
}
BitVector ChangingRegs(TRI->getNumRegs());
collectChangingRegs(MF, TRI, ChangingRegs);
+ const TargetLowering *TLI = MF->getSubtarget().getTargetLowering();
+ unsigned SP = TLI->getStackPointerRegisterToSaveRestore();
RegDescribedVarsMap RegVars;
for (const auto &MBB : *MF) {
for (const auto &MI : MBB) {
if (!MI.isDebugValue()) {
// Not a DBG_VALUE instruction. It may clobber registers which describe
// some variables.
- applyToClobberedRegisters(MI, TRI, [&](unsigned RegNo) {
- if (ChangingRegs.test(RegNo))
- clobberRegisterUses(RegVars, RegNo, Result, MI);
- });
+ for (const MachineOperand &MO : MI.operands()) {
+ if (MO.isReg() && MO.isDef() && MO.getReg()) {
+ // If this is a register def operand, it may end a debug value
+ // range.
+ for (MCRegAliasIterator AI(MO.getReg(), TRI, true); AI.isValid();
+ ++AI)
+ if (ChangingRegs.test(*AI))
+ clobberRegisterUses(RegVars, *AI, Result, MI);
+ } else if (MO.isRegMask()) {
+ // If this is a register mask operand, clobber all debug values in
+ // non-CSRs.
+ for (int I = ChangingRegs.find_first(); I != -1;
+ I = ChangingRegs.find_next(I)) {
+ // Don't consider SP to be clobbered by register masks.
+ if (unsigned(I) != SP && TRI->isPhysicalRegister(I) &&
+ MO.clobbersPhysReg(I)) {
+ clobberRegisterUses(RegVars, I, Result, MI);
+ }
+ }
+ }
+ }
continue;
}
#include "llvm/Support/Debug.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Target/TargetInstrInfo.h"
+#include "llvm/Target/TargetLowering.h"
#include "llvm/Target/TargetRegisterInfo.h"
#include "llvm/Target/TargetSubtargetInfo.h"
#include <queue>
/// A definition of a register may mark the end of a range.
void LiveDebugValues::transferRegisterDef(MachineInstr &MI,
VarLocList &OpenRanges) {
+ MachineFunction *MF = MI.getParent()->getParent();
+ const TargetLowering *TLI = MF->getSubtarget().getTargetLowering();
+ unsigned SP = TLI->getStackPointerRegisterToSaveRestore();
for (const MachineOperand &MO : MI.operands()) {
- if (!(MO.isReg() && MO.isDef() && MO.getReg() &&
- TRI->isPhysicalRegister(MO.getReg())))
- continue;
- // Remove ranges of all aliased registers.
- for (MCRegAliasIterator RAI(MO.getReg(), TRI, true); RAI.isValid(); ++RAI)
+ if (MO.isReg() && MO.isDef() && MO.getReg() &&
+ TRI->isPhysicalRegister(MO.getReg())) {
+ // Remove ranges of all aliased registers.
+ for (MCRegAliasIterator RAI(MO.getReg(), TRI, true); RAI.isValid(); ++RAI)
+ OpenRanges.erase(std::remove_if(OpenRanges.begin(), OpenRanges.end(),
+ [&](const VarLoc &V) {
+ return (*RAI ==
+ isDescribedByReg(*V.MI));
+ }),
+ OpenRanges.end());
+ } else if (MO.isRegMask()) {
+ // Remove ranges of all clobbered registers. Register masks don't usually
+ // list SP as preserved. While the debug info may be off for an
+ // instruction or two around callee-cleanup calls, transferring the
+ // DEBUG_VALUE across the call is still a better user experience.
OpenRanges.erase(std::remove_if(OpenRanges.begin(), OpenRanges.end(),
[&](const VarLoc &V) {
- return (*RAI ==
- isDescribedByReg(*V.MI));
+ unsigned Reg = isDescribedByReg(*V.MI);
+ return Reg && Reg != SP &&
+ MO.clobbersPhysReg(Reg);
}),
OpenRanges.end());
+ }
}
}
# 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
--- |
; 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"
; 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
--- /dev/null
+; 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)
; 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.
; 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
; 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"
; 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: