maxjhandsome
/
llvm-project
forked from OSchip/llvm-project
1
0
Fork 0
Code Issues Pull Requests Packages Releases Wiki Activity

[CodeView] Add option to disable inline line tables. 

Summary:
This adds a clang option to disable inline line tables. When it is used,
the inliner uses the call site as the location of the inlined function instead of
marking it as an inline location with the function location.

See https://bugs.llvm.org/show_bug.cgi?id=42344

Reviewers: rnk

Subscribers: hiraditya, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D67723
This commit is contained in:
Amy Huang 2019-09-16 15:46:49 -07:00
parent 3dec30855e
commit 6d03890384
10 changed files with 177 additions and 11 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
clang/include/clang/Basic/CodeGenOptions.def
View File

@ -136,6 +136,8 @@ CODEGENOPT(FatalWarnings , 1, 0) ///< Set when -Wa,--fatal-warnings is
///< enabled.
CODEGENOPT(NoWarn , 1, 0) ///< Set when -Wa,--no-warn is enabled.
CODEGENOPT(EnableSegmentedStacks , 1, 0) ///< Set when -fsplit-stack is enabled.
CODEGENOPT(NoInlineLineTables, 1, 0) ///< Whether debug info should contain
///< inline line tables.
CODEGENOPT(NoImplicitFloat , 1, 0) ///< Set when -mno-implicit-float is enabled.
CODEGENOPT(NoInfsFPMath , 1, 0) ///< Assume FP arguments, results not +-Inf.
CODEGENOPT(NoSignedZeros , 1, 0) ///< Allow ignoring the signedness of FP zero

3
clang/include/clang/Driver/Options.td
View File

@ -1984,6 +1984,9 @@ def gcodeview_ghash : Flag<["-"], "gcodeview-ghash">,
HelpText<"Emit type record hashes in a .debug$H section">,
Flags<[CC1Option, CoreOption]>;
def gno_codeview_ghash : Flag<["-"], "gno-codeview-ghash">, Flags<[CoreOption]>;
def ginline_line_tables : Flag<["-"], "ginline-line-tables">, Flags<[CoreOption]>;
def gno_inline_line_tables : Flag<["-"], "gno-inline-line-tables">,
Flags<[CC1Option, CoreOption]>, HelpText<"Don't emit inline line tables">;
// Equivalent to our default dwarf version. Forces usual dwarf emission when
// CodeView is enabled.

4
clang/lib/CodeGen/CodeGenFunction.cpp
View File

@ -764,6 +764,10 @@ void CodeGenFunction::StartFunction(GlobalDecl GD,
Fn->addFnAttr("no-jump-tables",
llvm::toStringRef(CGM.getCodeGenOpts().NoUseJumpTables));
// Add no-inline-line-tables value.
if (CGM.getCodeGenOpts().NoInlineLineTables)
Fn->addFnAttr("no-inline-line-tables");
// Add profile-sample-accurate value.
if (CGM.getCodeGenOpts().ProfileSampleAccurate)
Fn->addFnAttr("profile-sample-accurate");

6
clang/lib/Driver/ToolChains/Clang.cpp
View File

@ -3296,6 +3296,12 @@ static void RenderDebugOptions(const ToolChain &TC, const Driver &D,
}
}
// Omit inline line tables if requested.
if (!Args.hasFlag(options::OPT_ginline_line_tables,
options::OPT_gno_inline_line_tables, false)) {
CmdArgs.push_back("-gno-inline-line-tables");
}
// Adjust the debug info kind for the given toolchain.
TC.adjustDebugInfoKind(DebugInfoKind, Args);

1
clang/lib/Frontend/CompilerInvocation.cpp
View File

@ -806,6 +806,7 @@ static bool ParseCodeGenArgs(CodeGenOptions &Opts, ArgList &Args, InputKind IK,
Opts.RecordCommandLine = Args.getLastArgValue(OPT_record_command_line);
Opts.MergeAllConstants = Args.hasArg(OPT_fmerge_all_constants);
Opts.NoCommon = Args.hasArg(OPT_fno_common);
Opts.NoInlineLineTables = Args.hasArg(OPT_gno_inline_line_tables);
Opts.NoImplicitFloat = Args.hasArg(OPT_no_implicit_float);
Opts.OptimizeSize = getOptimizationLevelSize(Args);
Opts.SimplifyLibCalls = !(Args.hasArg(OPT_fno_builtin) ||

24
clang/test/CodeGen/debug-info-no-inline-line-tables.c Normal file
View File

@ -0,0 +1,24 @@
// RUN: %clang_cc1 -triple x86_64-windows-msvc -debug-info-kind=limited \
// RUN: -gno-inline-line-tables -emit-llvm -o - %s | FileCheck %s
int x;
__attribute((always_inline)) void f() {
x += 1;
}
int main() {
f();
x += 2;
return x;
}
// Check that clang emits the location of the call site and not the inlined
// function in the debug info.
// CHECK: define dso_local i32 @main()
// CHECK: %{{.+}} = load i32, i32* @x, align 4, !dbg [[DbgLoc:![0-9]+]]
// Check that the no-inline-line-tables attribute is added.
// CHECK: attributes #0 = {{.*}}"no-inline-line-tables"{{.*}}
// CHECK: attributes #1 = {{.*}}"no-inline-line-tables"{{.*}}
// CHECK: [[DbgLoc]] = !DILocation(line: 9,
// CHECK-NOT: inlinedAt:

7
llvm/docs/LangRef.rst
View File

@ -1452,6 +1452,13 @@ example:
``naked``
This attribute disables prologue / epilogue emission for the
function. This can have very system-specific consequences.
``"no-inline-line-tables"``
When this attribute is set to true, the inliner discards source locations
when inlining code and instead uses the source location of the call site.
Breakpoints set on code that was inlined into the current function will
not fire during the execution of the inlined call sites. If the debugger
stops inside an inlined call site, it will appear to be stopped at the
outermost inlined call site.
``no-jump-tables``
When this attribute is set to true, the jump tables and lookup tables that
can be generated from a switch case lowering are disabled.

1
llvm/include/llvm/IR/Attributes.td
View File

@ -220,6 +220,7 @@ def NoInfsFPMath : StrBoolAttr<"no-infs-fp-math">;
def NoNansFPMath : StrBoolAttr<"no-nans-fp-math">;
def UnsafeFPMath : StrBoolAttr<"unsafe-fp-math">;
def NoJumpTables : StrBoolAttr<"no-jump-tables">;
def NoInlineLineTables : StrBoolAttr<"no-inline-line-tables">;
def ProfileSampleAccurate : StrBoolAttr<"profile-sample-accurate">;
class CompatRule<string F> {

41
llvm/lib/Transforms/Utils/InlineFunction.cpp
View File

@ -1405,6 +1405,10 @@ static void fixupLineNumbers(Function *Fn, Function::iterator FI,
// other.
DenseMap<const MDNode *, MDNode *> IANodes;
// Check if we are not generating inline line tables and want to use
// the call site location instead.
bool NoInlineLineTables = Fn->hasFnAttribute("no-inline-line-tables");
for (; FI != Fn->end(); ++FI) {
for (BasicBlock::iterator BI = FI->begin(), BE = FI->end();
BI != BE; ++BI) {
@ -1416,20 +1420,22 @@ static void fixupLineNumbers(Function *Fn, Function::iterator FI,
BI->setMetadata(LLVMContext::MD_loop, NewLoopID);
}
if (DebugLoc DL = BI->getDebugLoc()) {
DebugLoc IDL =
inlineDebugLoc(DL, InlinedAtNode, BI->getContext(), IANodes);
BI->setDebugLoc(IDL);
continue;
}
if (!NoInlineLineTables)
if (DebugLoc DL = BI->getDebugLoc()) {
DebugLoc IDL =
inlineDebugLoc(DL, InlinedAtNode, BI->getContext(), IANodes);
BI->setDebugLoc(IDL);
continue;
}
if (CalleeHasDebugInfo)
if (CalleeHasDebugInfo && !NoInlineLineTables)
continue;
// If the inlined instruction has no line number, make it look as if it
// originates from the call location. This is important for
// ((__always_inline__, __nodebug__)) functions which must use caller
// location for all instructions in their function body.
// If the inlined instruction has no line number, or if inline info
// is not being generated, make it look as if it originates from the call
// location. This is important for ((__always_inline, __nodebug__))
// functions which must use caller location for all instructions in their
// function body.
// Don't update static allocas, as they may get moved later.
if (auto *AI = dyn_cast<AllocaInst>(BI))
@ -1438,6 +1444,19 @@ static void fixupLineNumbers(Function *Fn, Function::iterator FI,
BI->setDebugLoc(TheCallDL);
}
// Remove debug info intrinsics if we're not keeping inline info.
if (NoInlineLineTables) {
BasicBlock::iterator BI = FI->begin();
while (BI != FI->end()) {
if (isa<DbgInfoIntrinsic>(BI)) {
BI = BI->eraseFromParent();
continue;
}
++BI;
}
}
}
}

99
llvm/test/Transforms/Inline/no-inline-line-tables.ll Normal file
View File

@ -0,0 +1,99 @@
; RUN: opt < %s -inline -S | FileCheck %s
; This tests that functions with the attribute `no-inline-line-tables` have the
; correct debug information when they are inlined.
; ModuleID = 't.c'
source_filename = "t.c"
target datalayout = "e-m:w-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"
target triple = "x86_64-unknown-windows-msvc"
; Function Attrs: alwaysinline nounwind
define dso_local i32 @f(i32 %x) #0 !dbg !7 {
entry:
%x.addr = alloca i32, align 4
store i32 %x, i32* %x.addr, align 4
call void @llvm.dbg.declare(metadata i32* %x.addr, metadata !12, metadata !DIExpression()), !dbg !13
%0 = load i32, i32* %x.addr, align 4, !dbg !14
ret i32 %0, !dbg !14
}
; Function Attrs: nounwind readnone speculatable willreturn
declare void @llvm.dbg.declare(metadata, metadata, metadata) #1
; Function Attrs: alwaysinline nounwind
define i32 @g(i32 %x) #0 !dbg !15 {
entry:
%x.addr = alloca i32, align 4
store i32 %x, i32* %x.addr, align 4
call void @llvm.dbg.declare(metadata i32* %x.addr, metadata !16, metadata !DIExpression()), !dbg !17
br label %L, !dbg !17
L: ; preds = %entry
call void @llvm.dbg.label(metadata !18), !dbg !19
store i32 42, i32* %x.addr, align 4, !dbg !20
%0 = load i32, i32* %x.addr, align 4, !dbg !21
ret i32 %0, !dbg !21
}
; Function Attrs: nounwind readnone speculatable willreturn
declare void @llvm.dbg.label(metadata) #1
; Check that debug info for inlined code uses the call location and that debug
; intrinsics are removed.
; Function Attrs: noinline nounwind optnone
define i32 @main() #2 !dbg !22 {
entry:
; CHECK-LABEL: @main()
; CHECK-NOT: @f
; CHECK-NOT: @llvm.dbg.declare
; CHECK: %{{[0-9]+}} = load i32, i32* %x.addr.i, align 4, !dbg ![[VAR1:[0-9]+]]
%call = call i32 @f(i32 3), !dbg !25
; Another test for inlining debug intrinsics where the intrinsic appears at the
; start of the basic block.
; CHECK-NOT: @g
; CHECK-NOT: @llvm.dbg.label
; CHECK: %{{[0-9]+}} = load i32, i32* %x.addr.i1, align 4, !dbg ![[VAR2:[0-9]+]]
%call1 = call i32 @g(i32 340), !dbg !26
ret i32 0, !dbg !27
}
; CHECK: ![[VAR1]] = !DILocation(line: 10, scope: ![[SCOPE:[0-9]+]])
; CHECK: ![[VAR2]] = !DILocation(line: 11, scope: ![[SCOPE]])
attributes #0 = { alwaysinline nounwind "no-inline-line-tables" }
attributes #2 = { noinline nounwind optnone "no-inline-line-tables"}
!llvm.dbg.cu = !{!0}
!llvm.module.flags = !{!3, !4, !5}
!llvm.ident = !{!6}
!0 = distinct !DICompileUnit(language: DW_LANG_C99, file: !1, producer: "clang version 10.0.0 (https://github.com/llvm/llvm-project.git 03ec3a12a94bbbaa11999b6da3a43221a5aa54a5)", isOptimized: false, runtimeVersion: 0, emissionKind: FullDebug, enums: !2, nameTableKind: None)
!1 = !DIFile(filename: "<stdin>", directory: "/usr/local/google/home/akhuang/testing/inline-line-tables", checksumkind: CSK_MD5, checksum: "38a4785b48742d3ea655b8f3461436a4")
!2 = !{}
!3 = !{i32 2, !"CodeView", i32 1}
!4 = !{i32 2, !"Debug Info Version", i32 3}
!5 = !{i32 1, !"wchar_size", i32 4}
!6 = !{!"clang version 10.0.0 (https://github.com/llvm/llvm-project.git 03ec3a12a94bbbaa11999b6da3a43221a5aa54a5)"}
!7 = distinct !DISubprogram(name: "f", scope: !8, file: !8, line: 1, type: !9, scopeLine: 1, flags: DIFlagPrototyped, spFlags: DISPFlagDefinition, unit: !0, retainedNodes: !2)
!8 = !DIFile(filename: "t.c", directory: "/usr/local/google/home/akhuang/testing/inline-line-tables", checksumkind: CSK_MD5, checksum: "38a4785b48742d3ea655b8f3461436a4")
!9 = !DISubroutineType(types: !10)
!10 = !{!11, !11}
!11 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
!12 = !DILocalVariable(name: "x", arg: 1, scope: !7, file: !8, line: 1, type: !11)
!13 = !DILocation(line: 1, scope: !7)
!14 = !DILocation(line: 2, scope: !7)
!15 = distinct !DISubprogram(name: "g", scope: !8, file: !8, line: 4, type: !9, scopeLine: 4, flags: DIFlagPrototyped, spFlags: DISPFlagDefinition, unit: !0, retainedNodes: !2)
!16 = !DILocalVariable(name: "x", arg: 1, scope: !15, file: !8, line: 4, type: !11)
!17 = !DILocation(line: 4, scope: !15)
!18 = !DILabel(scope: !15, name: "L", file: !8, line: 5)
!19 = !DILocation(line: 5, scope: !15)
!20 = !DILocation(line: 6, scope: !15)
!21 = !DILocation(line: 7, scope: !15)
!22 = distinct !DISubprogram(name: "main", scope: !8, file: !8, line: 9, type: !23, scopeLine: 9, spFlags: DISPFlagDefinition, unit: !0, retainedNodes: !2)
!23 = !DISubroutineType(types: !24)
!24 = !{!11}
!25 = !DILocation(line: 10, scope: !22)
!26 = !DILocation(line: 11, scope: !22)
!27 = !DILocation(line: 12, scope: !22)