From 82550fed5c17afbe76f75bedc99ae9d27e5afc92 Mon Sep 17 00:00:00 2001 From: Saleem Abdulrasool Date: Tue, 12 May 2015 23:36:18 +0000 Subject: [PATCH] CodeGen: ignore DEBUG_VALUE nodes in KILL tagging DEBUG_VALUE nodes do not take part in code generation. Ignore them when performing KILL updates. Addresses PR23486. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237211 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/CodeGen/ScheduleDAGInstrs.cpp | 6 ++ test/CodeGen/ARM/sched-it-debug-nodes.ll | 88 ++++++++++++++++++++++++ 2 files changed, 94 insertions(+) create mode 100644 test/CodeGen/ARM/sched-it-debug-nodes.ll diff --git a/lib/CodeGen/ScheduleDAGInstrs.cpp b/lib/CodeGen/ScheduleDAGInstrs.cpp index 583ed38f313..b4a34be759c 100644 --- a/lib/CodeGen/ScheduleDAGInstrs.cpp +++ b/lib/CodeGen/ScheduleDAGInstrs.cpp @@ -1115,6 +1115,12 @@ static void toggleBundleKillFlag(MachineInstr *MI, unsigned Reg, if (!MO->isReg() || MO->isDef() || Reg != MO->getReg()) continue; + // DEBUG_VALUE nodes do not contribute to code generation and should + // always be ignored. Failure to do so may result in trying to modify + // KILL flags on DEBUG_VALUE nodes, which is distressing. + if (MO->isDebug()) + continue; + // If the register has the internal flag then it could be killing an // internal def of the register. In this case, just skip. We only want // to toggle the flag on operands visible outside the bundle. diff --git a/test/CodeGen/ARM/sched-it-debug-nodes.ll b/test/CodeGen/ARM/sched-it-debug-nodes.ll new file mode 100644 index 00000000000..7906e7c7581 --- /dev/null +++ b/test/CodeGen/ARM/sched-it-debug-nodes.ll @@ -0,0 +1,88 @@ +; RUN: llc -mtriple thumbv7 -print-before=post-RA-sched -print-after=post-RA-sched %s -o /dev/null 2>&1 | FileCheck %s + +; ModuleID = '' +target datalayout = "e-m:e-p:32:32-i64:64-v128:64:128-a:0:32-n32-S64" +target triple = "thumbv7" + +%struct.s = type opaque + +; Function Attrs: nounwind +define arm_aapcscc i32 @f(%struct.s* %s, i32 %u, i8* %b, i32 %n) #0 { +entry: + tail call void @llvm.dbg.value(metadata %struct.s* %s, i64 0, metadata !19, metadata !28), !dbg !29 + tail call void @llvm.dbg.value(metadata i32 %u, i64 0, metadata !20, metadata !28), !dbg !29 + tail call void @llvm.dbg.value(metadata i8* %b, i64 0, metadata !21, metadata !28), !dbg !29 + tail call void @llvm.dbg.value(metadata i32 %n, i64 0, metadata !22, metadata !28), !dbg !29 + %cmp = icmp ult i32 %n, 4, !dbg !30 + br i1 %cmp, label %return, label %if.end, !dbg !32 + +if.end: ; preds = %entry + tail call arm_aapcscc void @g(%struct.s* %s, i8* %b, i32 %n) #3, !dbg !33 + br label %return, !dbg !34 + +return: ; preds = %entry, %if.end + %retval.0 = phi i32 [ 0, %if.end ], [ -1, %entry ] + ret i32 %retval.0, !dbg !35 +} + +; NOTE: This is checking that the register in the DEBUG_VALUE node is not +; accidentally being marked as KILL. The DBG_VALUE node gets introduced in +; If-Conversion, and gets bundled into the IT block. The Post RA Scheduler +; attempts to schedule the Machine Instr, and tries to tag the register in the +; debug value as KILL'ed, resulting in a DEBUG_VALUE node changing codegen! (or +; hopefully, triggering an assert). + +; CHECK: BUNDLE %ITSTATE +; CHECK: * DBG_VALUE %R1, %noreg, !"u" +; CHECK-NOT: * DBG_VALUE %R1, %noreg, !"u" + +declare arm_aapcscc void @g(%struct.s*, i8*, i32) #1 + +; Function Attrs: nounwind readnone +declare void @llvm.dbg.value(metadata, i64, metadata, metadata) #2 + +attributes #0 = { nounwind "less-precise-fpmad"="false" "no-frame-pointer-elim"="false" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "no-realign-stack" "stack-protector-buffer-size"="8" "unsafe-fp-math"="false" "use-soft-float"="false" } +attributes #1 = { "less-precise-fpmad"="false" "no-frame-pointer-elim"="false" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "no-realign-stack" "stack-protector-buffer-size"="8" "unsafe-fp-math"="false" "use-soft-float"="false" } +attributes #2 = { nounwind readnone } +attributes #3 = { nounwind } + +!llvm.dbg.cu = !{!0} +!llvm.module.flags = !{!23, !24, !25, !26} +!llvm.ident = !{!27} + +!0 = !DICompileUnit(language: DW_LANG_C99, file: !1, producer: "clang version 3.7.0 (llvm/trunk 237059)", isOptimized: true, runtimeVersion: 0, emissionKind: 1, enums: !2, retainedTypes: !2, subprograms: !3, globals: !2, imports: !2) +!1 = !DIFile(filename: "", directory: "/Users/compnerd/Source/llvm") +!2 = !{} +!3 = !{!4} +!4 = !DISubprogram(name: "f", scope: !5, file: !5, line: 9, type: !6, isLocal: false, isDefinition: true, scopeLine: 9, flags: DIFlagPrototyped, isOptimized: true, function: i32 (%struct.s*, i32, i8*, i32)* @f, variables: !18) +!5 = !DIFile(filename: "", directory: "/Users/compnerd/Source/llvm") +!6 = !DISubroutineType(types: !7) +!7 = !{!8, !9, !12, !13, !17} +!8 = !DIBasicType(name: "int", size: 32, align: 32, encoding: DW_ATE_signed) +!9 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !10, size: 32, align: 32) +!10 = !DIDerivedType(tag: DW_TAG_typedef, name: "s", file: !5, line: 5, baseType: !11) +!11 = !DICompositeType(tag: DW_TAG_structure_type, name: "s", file: !5, line: 5, flags: DIFlagFwdDecl) +!12 = !DIBasicType(name: "unsigned int", size: 32, align: 32, encoding: DW_ATE_unsigned) +!13 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !14, size: 32, align: 32) +!14 = !DIDerivedType(tag: DW_TAG_const_type, baseType: !15) +!15 = !DIDerivedType(tag: DW_TAG_typedef, name: "uint8_t", file: !5, line: 2, baseType: !16) +!16 = !DIBasicType(name: "unsigned char", size: 8, align: 8, encoding: DW_ATE_unsigned_char) +!17 = !DIDerivedType(tag: DW_TAG_typedef, name: "size_t", file: !5, line: 3, baseType: !12) +!18 = !{!19, !20, !21, !22} +!19 = !DILocalVariable(tag: DW_TAG_arg_variable, name: "s", arg: 1, scope: !4, file: !5, line: 9, type: !9) +!20 = !DILocalVariable(tag: DW_TAG_arg_variable, name: "u", arg: 2, scope: !4, file: !5, line: 9, type: !12) +!21 = !DILocalVariable(tag: DW_TAG_arg_variable, name: "b", arg: 3, scope: !4, file: !5, line: 9, type: !13) +!22 = !DILocalVariable(tag: DW_TAG_arg_variable, name: "n", arg: 4, scope: !4, file: !5, line: 9, type: !17) +!23 = !{i32 2, !"Dwarf Version", i32 4} +!24 = !{i32 2, !"Debug Info Version", i32 3} +!25 = !{i32 1, !"wchar_size", i32 4} +!26 = !{i32 1, !"min_enum_size", i32 4} +!27 = !{!"clang version 3.7.0 (llvm/trunk 237059)"} +!28 = !DIExpression() +!29 = !DILocation(line: 9, scope: !4) +!30 = !DILocation(line: 10, scope: !31) +!31 = distinct !DILexicalBlock(scope: !4, file: !5, line: 10) +!32 = !DILocation(line: 10, scope: !4) +!33 = !DILocation(line: 13, scope: !4) +!34 = !DILocation(line: 14, scope: !4) +!35 = !DILocation(line: 15, scope: !4) -- 2.40.0