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[PATCH v1] perf build: Don't compile demangle-cxx.cpp if not necessary

Ian Rogers posted 1 patch 2 years, 8 months ago 
tools/perf/Makefile.config   |  1 +
tools/perf/util/Build        |  2 +-
tools/perf/util/symbol-elf.c | 27 +++++++++++++++++++++++++++
3 files changed, 29 insertions(+), 1 deletion(-)
[PATCH v1] perf build: Don't compile demangle-cxx.cpp if not necessary
Posted by Ian Rogers 2 years, 8 months ago 
demangle-cxx.cpp requires a C++ compiler, but feature checks may fail
because of the absence of this. Add a CONFIG_CXX_DEMANGLE so that the
source isn't built if not supported. Copy libbfd and cplus demangle
variants to a weak symbol-elf.c version so they aren't dependent on
C++. These variants are only built with the build option
BUILD_NONDISTRO=1.

Signed-off-by: Ian Rogers <irogers@google.com>
---
 tools/perf/Makefile.config   |  1 +
 tools/perf/util/Build        |  2 +-
 tools/perf/util/symbol-elf.c | 27 +++++++++++++++++++++++++++
 3 files changed, 29 insertions(+), 1 deletion(-)

diff --git a/tools/perf/Makefile.config b/tools/perf/Makefile.config
index 71442c54c25f..5f0f24b56f50 100644
--- a/tools/perf/Makefile.config
+++ b/tools/perf/Makefile.config
@@ -923,6 +923,7 @@ ifndef NO_DEMANGLE
     EXTLIBS += -lstdc++
     CFLAGS += -DHAVE_CXA_DEMANGLE_SUPPORT
     CXXFLAGS += -DHAVE_CXA_DEMANGLE_SUPPORT
+    $(call detected,CONFIG_CXX_DEMANGLE)
   endif
   ifdef BUILD_NONDISTRO
     ifeq ($(filter -liberty,$(EXTLIBS)),)
diff --git a/tools/perf/util/Build b/tools/perf/util/Build
index bd18fe5f2719..f9df1df1eec0 100644
--- a/tools/perf/util/Build
+++ b/tools/perf/util/Build
@@ -214,7 +214,7 @@ perf-$(CONFIG_ZSTD) += zstd.o
 
 perf-$(CONFIG_LIBCAP) += cap.o
 
-perf-y += demangle-cxx.o
+perf-$(CONFIG_CXX_DEMANGLE) += demangle-cxx.o
 perf-y += demangle-ocaml.o
 perf-y += demangle-java.o
 perf-y += demangle-rust.o
diff --git a/tools/perf/util/symbol-elf.c b/tools/perf/util/symbol-elf.c
index 35724f6a84fa..cd08bdb9824f 100644
--- a/tools/perf/util/symbol-elf.c
+++ b/tools/perf/util/symbol-elf.c
@@ -31,6 +31,13 @@
 #include <bfd.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
+
 #ifndef EM_AARCH64
 #define EM_AARCH64	183  /* ARM 64 bit */
 #endif
@@ -271,6 +278,26 @@ static bool want_demangle(bool is_kernel_sym)
 	return is_kernel_sym ? symbol_conf.demangle_kernel : symbol_conf.demangle;
 }
 
+/*
+ * Demangle C++ function signature, typically replaced by demangle-cxx.cpp
+ * version.
+ */
+__weak char *cxx_demangle_sym(const char *str __maybe_unused, 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);
+#else
+	return NULL;
+#endif
+}
+
 static char *demangle_sym(struct dso *dso, int kmodule, const char *elf_name)
 {
 	char *demangled = NULL;
-- 
2.40.0.634.g4ca3ef3211-goog
Re: [PATCH v1] perf build: Don't compile demangle-cxx.cpp if not necessary
Posted by Ian Rogers 2 years, 7 months ago 
On Mon, Apr 17, 2023 at 12:25 PM Ian Rogers <irogers@google.com> wrote:
>
> demangle-cxx.cpp requires a C++ compiler, but feature checks may fail
> because of the absence of this. Add a CONFIG_CXX_DEMANGLE so that the
> source isn't built if not supported. Copy libbfd and cplus demangle
> variants to a weak symbol-elf.c version so they aren't dependent on
> C++. These variants are only built with the build option
> BUILD_NONDISTRO=1.
>
> Signed-off-by: Ian Rogers <irogers@google.com>

Testing on arm and noticed we hadn't picked this one up.

Thanks,
Ian

> ---
>  tools/perf/Makefile.config   |  1 +
>  tools/perf/util/Build        |  2 +-
>  tools/perf/util/symbol-elf.c | 27 +++++++++++++++++++++++++++
>  3 files changed, 29 insertions(+), 1 deletion(-)
>
> diff --git a/tools/perf/Makefile.config b/tools/perf/Makefile.config
> index 71442c54c25f..5f0f24b56f50 100644
> --- a/tools/perf/Makefile.config
> +++ b/tools/perf/Makefile.config
> @@ -923,6 +923,7 @@ ifndef NO_DEMANGLE
>      EXTLIBS += -lstdc++
>      CFLAGS += -DHAVE_CXA_DEMANGLE_SUPPORT
>      CXXFLAGS += -DHAVE_CXA_DEMANGLE_SUPPORT
> +    $(call detected,CONFIG_CXX_DEMANGLE)
>    endif
>    ifdef BUILD_NONDISTRO
>      ifeq ($(filter -liberty,$(EXTLIBS)),)
> diff --git a/tools/perf/util/Build b/tools/perf/util/Build
> index bd18fe5f2719..f9df1df1eec0 100644
> --- a/tools/perf/util/Build
> +++ b/tools/perf/util/Build
> @@ -214,7 +214,7 @@ perf-$(CONFIG_ZSTD) += zstd.o
>
>  perf-$(CONFIG_LIBCAP) += cap.o
>
> -perf-y += demangle-cxx.o
> +perf-$(CONFIG_CXX_DEMANGLE) += demangle-cxx.o
>  perf-y += demangle-ocaml.o
>  perf-y += demangle-java.o
>  perf-y += demangle-rust.o
> diff --git a/tools/perf/util/symbol-elf.c b/tools/perf/util/symbol-elf.c
> index 35724f6a84fa..cd08bdb9824f 100644
> --- a/tools/perf/util/symbol-elf.c
> +++ b/tools/perf/util/symbol-elf.c
> @@ -31,6 +31,13 @@
>  #include <bfd.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
> +
>  #ifndef EM_AARCH64
>  #define EM_AARCH64     183  /* ARM 64 bit */
>  #endif
> @@ -271,6 +278,26 @@ static bool want_demangle(bool is_kernel_sym)
>         return is_kernel_sym ? symbol_conf.demangle_kernel : symbol_conf.demangle;
>  }
>
> +/*
> + * Demangle C++ function signature, typically replaced by demangle-cxx.cpp
> + * version.
> + */
> +__weak char *cxx_demangle_sym(const char *str __maybe_unused, 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);
> +#else
> +       return NULL;
> +#endif
> +}
> +
>  static char *demangle_sym(struct dso *dso, int kmodule, const char *elf_name)
>  {
>         char *demangled = NULL;
> --
> 2.40.0.634.g4ca3ef3211-goog
>
Re: [PATCH v1] perf build: Don't compile demangle-cxx.cpp if not necessary
Posted by Arnaldo Carvalho de Melo 2 years, 6 months ago 
Em Wed, Apr 26, 2023 at 10:27:42PM -0700, Ian Rogers escreveu:
> On Mon, Apr 17, 2023 at 12:25 PM Ian Rogers <irogers@google.com> wrote:
> >
> > demangle-cxx.cpp requires a C++ compiler, but feature checks may fail
> > because of the absence of this. Add a CONFIG_CXX_DEMANGLE so that the
> > source isn't built if not supported. Copy libbfd and cplus demangle
> > variants to a weak symbol-elf.c version so they aren't dependent on
> > C++. These variants are only built with the build option
> > BUILD_NONDISTRO=1.
> >
> > Signed-off-by: Ian Rogers <irogers@google.com>
> 
> Testing on arm and noticed we hadn't picked this one up.

Thanks, applied.

- Arnaldo

 
> Thanks,
> Ian
> 
> > ---
> >  tools/perf/Makefile.config   |  1 +
> >  tools/perf/util/Build        |  2 +-
> >  tools/perf/util/symbol-elf.c | 27 +++++++++++++++++++++++++++
> >  3 files changed, 29 insertions(+), 1 deletion(-)
> >
> > diff --git a/tools/perf/Makefile.config b/tools/perf/Makefile.config
> > index 71442c54c25f..5f0f24b56f50 100644
> > --- a/tools/perf/Makefile.config
> > +++ b/tools/perf/Makefile.config
> > @@ -923,6 +923,7 @@ ifndef NO_DEMANGLE
> >      EXTLIBS += -lstdc++
> >      CFLAGS += -DHAVE_CXA_DEMANGLE_SUPPORT
> >      CXXFLAGS += -DHAVE_CXA_DEMANGLE_SUPPORT
> > +    $(call detected,CONFIG_CXX_DEMANGLE)
> >    endif
> >    ifdef BUILD_NONDISTRO
> >      ifeq ($(filter -liberty,$(EXTLIBS)),)
> > diff --git a/tools/perf/util/Build b/tools/perf/util/Build
> > index bd18fe5f2719..f9df1df1eec0 100644
> > --- a/tools/perf/util/Build
> > +++ b/tools/perf/util/Build
> > @@ -214,7 +214,7 @@ perf-$(CONFIG_ZSTD) += zstd.o
> >
> >  perf-$(CONFIG_LIBCAP) += cap.o
> >
> > -perf-y += demangle-cxx.o
> > +perf-$(CONFIG_CXX_DEMANGLE) += demangle-cxx.o
> >  perf-y += demangle-ocaml.o
> >  perf-y += demangle-java.o
> >  perf-y += demangle-rust.o
> > diff --git a/tools/perf/util/symbol-elf.c b/tools/perf/util/symbol-elf.c
> > index 35724f6a84fa..cd08bdb9824f 100644
> > --- a/tools/perf/util/symbol-elf.c
> > +++ b/tools/perf/util/symbol-elf.c
> > @@ -31,6 +31,13 @@
> >  #include <bfd.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
> > +
> >  #ifndef EM_AARCH64
> >  #define EM_AARCH64     183  /* ARM 64 bit */
> >  #endif
> > @@ -271,6 +278,26 @@ static bool want_demangle(bool is_kernel_sym)
> >         return is_kernel_sym ? symbol_conf.demangle_kernel : symbol_conf.demangle;
> >  }
> >
> > +/*
> > + * Demangle C++ function signature, typically replaced by demangle-cxx.cpp
> > + * version.
> > + */
> > +__weak char *cxx_demangle_sym(const char *str __maybe_unused, 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);
> > +#else
> > +       return NULL;
> > +#endif
> > +}
> > +
> >  static char *demangle_sym(struct dso *dso, int kmodule, const char *elf_name)
> >  {
> >         char *demangled = NULL;
> > --
> > 2.40.0.634.g4ca3ef3211-goog
> >

-- 

- Arnaldo

Patchew 2.1-devel-b67e4c2

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