Commit 3b4e4efe authored by Ian Rogers's avatar Ian Rogers Committed by Arnaldo Carvalho de Melo
Browse files

perf symbol: Add abi::__cxa_demangle C++ demangling support 



Refactor C++ demangling out of symbol-elf into its own files similar
to other languages. Add abi::__cxa_demangle support. As the other
demanglers are not shippable with distributions, this brings back C++
demangling in a common case. It isn't perfect as the support for
optionally demangling arguments and modifiers isn't present.

Signed-off-by: default avatarIan Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andres Freund <andres@anarazel.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Martin Liška <mliska@suse.cz>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Pavithra Gurushankar <gpavithrasha@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Quentin Monnet <quentin@isovalent.com>
Cc: Roberto Sassu <roberto.sassu@huawei.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tiezhu Yang <yangtiezhu@loongson.cn>
Cc: Tom Rix <trix@redhat.com>
Cc: Yang Jihong <yangjihong1@huawei.com>
Cc: llvm@lists.linux.dev
Link: https://lore.kernel.org/r/20230311065753.3012826-2-irogers@google.com


Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
parent 4c72e2b3

tools/perf/Makefile.config

+14 −15
Original line number Diff line number Diff line
@@ -914,6 +914,7 @@ ifdef BUILD_NONDISTRO 
  endif



  CFLAGS += -DHAVE_LIBBFD_SUPPORT

  CXXFLAGS += -DHAVE_LIBBFD_SUPPORT

  ifeq ($(feature-libbfd-buildid), 1)

    CFLAGS += -DHAVE_LIBBFD_BUILDID_SUPPORT

  else
@@ -921,26 +922,24 @@ ifdef BUILD_NONDISTRO 
  endif

endif



ifdef NO_DEMANGLE

  CFLAGS += -DNO_DEMANGLE

else

ifndef NO_DEMANGLE

  $(call feature_check,cxa-demangle)

  ifeq ($(feature-cxa-demangle), 1)

    EXTLIBS += -lstdc++

    CFLAGS += -DHAVE_CXA_DEMANGLE_SUPPORT

    CXXFLAGS += -DHAVE_CXA_DEMANGLE_SUPPORT

  endif

  ifdef BUILD_NONDISTRO

    ifeq ($(filter -liberty,$(EXTLIBS)),)

      ifdef HAVE_CPLUS_DEMANGLE_SUPPORT

        EXTLIBS += -liberty

      else

      $(call feature_check,cplus-demangle)

      ifeq ($(feature-cplus-demangle), 1)

        EXTLIBS += -liberty

      endif

    endif

    endif

  endif



    ifneq ($(filter -liberty,$(EXTLIBS)),)

      CFLAGS += -DHAVE_CPLUS_DEMANGLE_SUPPORT

  else

    CFLAGS += -DNO_DEMANGLE

      CXXFLAGS += -DHAVE_CPLUS_DEMANGLE_SUPPORT

    endif

  endif

endif

tools/perf/util/Build

+1 −0
Original line number Diff line number Diff line
@@ -211,6 +211,7 @@ perf-$(CONFIG_ZSTD) += zstd.o 


perf-$(CONFIG_LIBCAP) += cap.o



perf-y += demangle-cxx.o

perf-y += demangle-ocaml.o

perf-y += demangle-java.o

perf-y += demangle-rust.o

tools/perf/util/demangle-cxx.cpp

0 → 100644
+50 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0

#include "demangle-cxx.h"

#include <stdlib.h>

#include <string.h>

#include <linux/compiler.h>



#ifdef HAVE_LIBBFD_SUPPORT

#define PACKAGE 'perf'

#include <bfd.h>

#endif



#ifdef HAVE_CXA_DEMANGLE_SUPPORT

#include <cxxabi.h>

#endif



#if defined(HAVE_LIBBFD_SUPPORT) || defined(HAVE_CPLUS_DEMANGLE_SUPPORT)

#ifndef DMGL_PARAMS

#define DMGL_PARAMS     (1 << 0)  /* Include function args */

#define DMGL_ANSI       (1 << 1)  /* Include const, volatile, etc */

#endif

#endif



/*

 * Demangle C++ function signature

 *

 * Note: caller is responsible for freeing demangled string

 */

extern "C"

char *cxx_demangle_sym(const char *str, bool params __maybe_unused,

                       bool modifiers __maybe_unused)

{

#ifdef HAVE_LIBBFD_SUPPORT

        int flags = (params ? DMGL_PARAMS : 0) | (modifiers ? DMGL_ANSI : 0);



        return bfd_demangle(NULL, str, flags);

#elif defined(HAVE_CPLUS_DEMANGLE_SUPPORT)

        int flags = (params ? DMGL_PARAMS : 0) | (modifiers ? DMGL_ANSI : 0);



        return cplus_demangle(str, flags);

#elif defined(HAVE_CXA_DEMANGLE_SUPPORT)

        size_t len = strlen(str);

        char *output = (char*)malloc(len);

        int status;



        output = abi::__cxa_demangle(str, output, &len, &status);

        return output;

#else

        return NULL;

#endif

}

tools/perf/util/demangle-cxx.h

0 → 100644
+16 −0
Original line number Diff line number Diff line 
/* SPDX-License-Identifier: GPL-2.0 */

#ifndef __PERF_DEMANGLE_CXX

#define __PERF_DEMANGLE_CXX 1



#ifdef __cplusplus

extern "C" {

#endif



char *cxx_demangle_sym(const char *str, bool params, bool modifiers);



#ifdef __cplusplus

}

#endif





#endif /* __PERF_DEMANGLE_CXX */

tools/perf/util/symbol-elf.c

+7 −30
Original line number Diff line number Diff line
@@ -12,6 +12,7 @@ 
#include "maps.h"

#include "symbol.h"

#include "symsrc.h"

#include "demangle-cxx.h"

#include "demangle-ocaml.h"

#include "demangle-java.h"

#include "demangle-rust.h"
@@ -25,6 +26,11 @@ 
#include <symbol/kallsyms.h>

#include <internal/lib.h>



#ifdef HAVE_LIBBFD_SUPPORT

#define PACKAGE 'perf'

#include <bfd.h>

#endif



#ifndef EM_AARCH64

#define EM_AARCH64	183  /* ARM 64 bit */

#endif
@@ -45,34 +51,6 @@ 


typedef Elf64_Nhdr GElf_Nhdr;



#ifndef DMGL_PARAMS

#define DMGL_NO_OPTS     0              /* For readability... */

#define DMGL_PARAMS      (1 << 0)       /* Include function args */

#define DMGL_ANSI        (1 << 1)       /* Include const, volatile, etc */

#endif



#ifdef HAVE_LIBBFD_SUPPORT

#define PACKAGE 'perf'

#include <bfd.h>

#else

#ifdef HAVE_CPLUS_DEMANGLE_SUPPORT

extern char *cplus_demangle(const char *, int);



static inline char *bfd_demangle(void __maybe_unused *v, const char *c, int i)

{

	return cplus_demangle(c, i);

}

#else

#ifdef NO_DEMANGLE

static inline char *bfd_demangle(void __maybe_unused *v,

				 const char __maybe_unused *c,

				 int __maybe_unused i)

{

	return NULL;

}

#endif

#endif

#endif



#ifndef HAVE_ELF_GETPHDRNUM_SUPPORT

static int elf_getphdrnum(Elf *elf, size_t *dst)
@@ -295,7 +273,6 @@ static bool want_demangle(bool is_kernel_sym) 


static char *demangle_sym(struct dso *dso, int kmodule, const char *elf_name)

{

	int demangle_flags = verbose > 0 ? (DMGL_PARAMS | DMGL_ANSI) : DMGL_NO_OPTS;

	char *demangled = NULL;



	/*
@@ -306,7 +283,7 @@ static char *demangle_sym(struct dso *dso, int kmodule, const char *elf_name) 
	if (!want_demangle(dso->kernel || kmodule))

	    return demangled;



	demangled = bfd_demangle(NULL, elf_name, demangle_flags);

	demangled = cxx_demangle_sym(elf_name, verbose > 0, verbose > 0);

	if (demangled == NULL) {

		demangled = ocaml_demangle_sym(elf_name);

		if (demangled == NULL) {