replica
/
hanchenye-llvm-project
2
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

[DebugInfo] Add -fuse-ctor-homing cc1 flag so we can turn on constructor homing only if limited debug info is already on. 

This adds a cc1 flag to enable constructor homing but doesn't turn on debug
info if it wasn't enabled already (which is what using
-debug-info-kind=constructor does). This will be used for testing, and won't
be needed anymore once ctor homing is used as default / merged into =limited.

Bug to enable ctor homing: https://bugs.llvm.org/show_bug.cgi?id=46537

Differential Revision: https://reviews.llvm.org/D85799
This commit is contained in:
Amy Huang 2020-08-13 15:48:55 -07:00
parent ab9fc8bae8
commit ae6523cd62
3 changed files with 28 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
clang/include/clang/Driver/Options.td
View File

@ -3691,6 +3691,8 @@ def mrelocation_model : Separate<["-"], "mrelocation-model">,
AutoNormalizeEnum;
def fno_math_builtin : Flag<["-"], "fno-math-builtin">,
HelpText<"Disable implicit builtin knowledge of math functions">;
def fuse_ctor_homing: Flag<["-"], "fuse-ctor-homing">,
HelpText<"Use constructor homing if we are using limited debug info already">;
}
def disable_llvm_verifier : Flag<["-"], "disable-llvm-verifier">,

6
clang/lib/Frontend/CompilerInvocation.cpp
View File

@ -775,6 +775,12 @@ static bool ParseCodeGenArgs(CodeGenOptions &Opts, ArgList &Args, InputKind IK,
else
Opts.setDebugInfo(static_cast<codegenoptions::DebugInfoKind>(Val));
}
// If -fuse-ctor-homing is set and limited debug info is already on, then use
// constructor homing.
if (Arg *A = Args.getLastArg(OPT_fuse_ctor_homing))
if (Opts.getDebugInfo() == codegenoptions::LimitedDebugInfo)
Opts.setDebugInfo(codegenoptions::DebugInfoConstructor);
if (Arg *A = Args.getLastArg(OPT_debugger_tuning_EQ)) {
unsigned Val = llvm::StringSwitch<unsigned>(A->getValue())
.Case("gdb", unsigned(llvm::DebuggerKind::GDB))

20
clang/test/CodeGenCXX/debug-info-ctor-homing-flag.cpp Normal file
View File

@ -0,0 +1,20 @@
// RUN: %clang -cc1 -debug-info-kind=constructor -emit-llvm %s -o - \
// RUN: | FileCheck %s -check-prefix=CTOR_HOMING
// RUN: %clang -cc1 -debug-info-kind=limited -fuse-ctor-homing -emit-llvm %s -o - \
// RUN: | FileCheck %s -check-prefix=CTOR_HOMING
// RUN: %clang -cc1 -debug-info-kind=standalone -fuse-ctor-homing -emit-llvm %s -o - \
// RUN: | FileCheck %s -check-prefix=FULL_DEBUG
// RUN: %clang -cc1 -debug-info-kind=line-tables-only -fuse-ctor-homing -emit-llvm %s -o - \
// RUN: | FileCheck %s -check-prefix=NO_DEBUG
// RUN: %clang -cc1 -fuse-ctor-homing -emit-llvm %s -o - \
// RUN: | FileCheck %s -check-prefix=NO_DEBUG
// This tests that the -fuse-ctor-homing is only used if limited debug info would have
// been used otherwise.
// CTOR_HOMING: !DICompositeType(tag: DW_TAG_structure_type, name: "A"{{.*}}flags: DIFlagFwdDecl
// FULL_DEBUG: !DICompositeType(tag: DW_TAG_structure_type, name: "A"{{.*}}DIFlagTypePassByValue
// NO_DEBUG-NOT: !DICompositeType(tag: DW_TAG_structure_type, name: "A"
struct A {
A();
} TestA;