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: Ian 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: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 50 insertions, 0 deletions

diff --git a/tools/perf/util/demangle-cxx.cpp b/tools/perf/util/demangle-cxx.cpp
new file mode 100644
index 000000000000..8708bcafd370
--- /dev/null
+++ b/tools/perf/util/demangle-cxx.cpp
@@ -0,0 +1,50 @@
+// 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
+}