From e9c4bcdd349eb00f6c704450a063b3dcbea25864 Mon Sep 17 00:00:00 2001 From: Stephane Eranian Date: Mon, 30 Nov 2015 10:02:20 +0100 Subject: [PATCH] perf symbols: add Java demangling support Add Java function descriptor demangling support. Something bfd cannot do. Use the JAVA_DEMANGLE_NORET flag to avoid decoding the return type of functions. Signed-off-by: Stephane Eranian Cc: Adrian Hunter Cc: Andi Kleen Cc: Carl Love Cc: David Ahern Cc: Jiri Olsa Cc: John McCutchan Cc: Namhyung Kim Cc: Pawel Moll Cc: Peter Zijlstra Cc: Sonny Rao Cc: Sukadev Bhattiprolu Link: http://lkml.kernel.org/r/1448874143-7269-2-git-send-email-eranian@google.com Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/Build | 1 + tools/perf/util/demangle-java.c | 199 ++++++++++++++++++++++++++++++++ tools/perf/util/demangle-java.h | 10 ++ tools/perf/util/symbol-elf.c | 3 + 4 files changed, 213 insertions(+) create mode 100644 tools/perf/util/demangle-java.c create mode 100644 tools/perf/util/demangle-java.h diff --git a/tools/perf/util/Build b/tools/perf/util/Build index 5eec53a3f4ac..edae107416b6 100644 --- a/tools/perf/util/Build +++ b/tools/perf/util/Build @@ -105,6 +105,7 @@ libperf-y += scripting-engines/ libperf-$(CONFIG_ZLIB) += zlib.o libperf-$(CONFIG_LZMA) += lzma.o +libperf-y += demangle-java.o CFLAGS_config.o += -DETC_PERFCONFIG="BUILD_STR($(ETC_PERFCONFIG_SQ))" diff --git a/tools/perf/util/demangle-java.c b/tools/perf/util/demangle-java.c new file mode 100644 index 000000000000..3e6062ab2cdd --- /dev/null +++ b/tools/perf/util/demangle-java.c @@ -0,0 +1,199 @@ +#include +#include +#include +#include "util.h" +#include "debug.h" +#include "symbol.h" + +#include "demangle-java.h" + +enum { + MODE_PREFIX = 0, + MODE_CLASS = 1, + MODE_FUNC = 2, + MODE_TYPE = 3, + MODE_CTYPE = 3, /* class arg */ +}; + +#define BASE_ENT(c, n) [c - 'A']=n +static const char *base_types['Z' - 'A' + 1] = { + BASE_ENT('B', "byte" ), + BASE_ENT('C', "char" ), + BASE_ENT('D', "double" ), + BASE_ENT('F', "float" ), + BASE_ENT('I', "int" ), + BASE_ENT('J', "long" ), + BASE_ENT('S', "short" ), + BASE_ENT('Z', "bool" ), +}; + +/* + * demangle Java symbol between str and end positions and stores + * up to maxlen characters into buf. The parser starts in mode. + * + * Use MODE_PREFIX to process entire prototype till end position + * Use MODE_TYPE to process return type if str starts on return type char + * + * Return: + * success: buf + * error : NULL + */ +static char * +__demangle_java_sym(const char *str, const char *end, char *buf, int maxlen, int mode) +{ + int rlen = 0; + int array = 0; + int narg = 0; + const char *q; + + if (!end) + end = str + strlen(str); + + for (q = str; q != end; q++) { + + if (rlen == (maxlen - 1)) + break; + + switch (*q) { + case 'L': + if (mode == MODE_PREFIX || mode == MODE_CTYPE) { + if (mode == MODE_CTYPE) { + if (narg) + rlen += scnprintf(buf + rlen, maxlen - rlen, ", "); + narg++; + } + rlen += scnprintf(buf + rlen, maxlen - rlen, "class "); + if (mode == MODE_PREFIX) + mode = MODE_CLASS; + } else + buf[rlen++] = *q; + break; + case 'B': + case 'C': + case 'D': + case 'F': + case 'I': + case 'J': + case 'S': + case 'Z': + if (mode == MODE_TYPE) { + if (narg) + rlen += scnprintf(buf + rlen, maxlen - rlen, ", "); + rlen += scnprintf(buf + rlen, maxlen - rlen, "%s", base_types[*q - 'A']); + while (array--) + rlen += scnprintf(buf + rlen, maxlen - rlen, "[]"); + array = 0; + narg++; + } else + buf[rlen++] = *q; + break; + case 'V': + if (mode == MODE_TYPE) { + rlen += scnprintf(buf + rlen, maxlen - rlen, "void"); + while (array--) + rlen += scnprintf(buf + rlen, maxlen - rlen, "[]"); + array = 0; + } else + buf[rlen++] = *q; + break; + case '[': + if (mode != MODE_TYPE) + goto error; + array++; + break; + case '(': + if (mode != MODE_FUNC) + goto error; + buf[rlen++] = *q; + mode = MODE_TYPE; + break; + case ')': + if (mode != MODE_TYPE) + goto error; + buf[rlen++] = *q; + narg = 0; + break; + case ';': + if (mode != MODE_CLASS && mode != MODE_CTYPE) + goto error; + /* safe because at least one other char to process */ + if (isalpha(*(q + 1))) + rlen += scnprintf(buf + rlen, maxlen - rlen, "."); + if (mode == MODE_CLASS) + mode = MODE_FUNC; + else if (mode == MODE_CTYPE) + mode = MODE_TYPE; + break; + case '/': + if (mode != MODE_CLASS && mode != MODE_CTYPE) + goto error; + rlen += scnprintf(buf + rlen, maxlen - rlen, "."); + break; + default : + buf[rlen++] = *q; + } + } + buf[rlen] = '\0'; + return buf; +error: + return NULL; +} + +/* + * Demangle Java function signature (openJDK, not GCJ) + * input: + * str: string to parse. String is not modified + * flags: comobination of JAVA_DEMANGLE_* flags to modify demangling + * return: + * if input can be demangled, then a newly allocated string is returned. + * if input cannot be demangled, then NULL is returned + * + * Note: caller is responsible for freeing demangled string + */ +char * +java_demangle_sym(const char *str, int flags) +{ + char *buf, *ptr; + char *p; + size_t len, l1 = 0; + + if (!str) + return NULL; + + /* find start of retunr type */ + p = strrchr(str, ')'); + if (!p) + return NULL; + + /* + * expansion factor estimated to 3x + */ + len = strlen(str) * 3 + 1; + buf = malloc(len); + if (!buf) + return NULL; + + buf[0] = '\0'; + if (!(flags & JAVA_DEMANGLE_NORET)) { + /* + * get return type first + */ + ptr = __demangle_java_sym(p + 1, NULL, buf, len, MODE_TYPE); + if (!ptr) + goto error; + + /* add space between return type and function prototype */ + l1 = strlen(buf); + buf[l1++] = ' '; + } + + /* process function up to return type */ + ptr = __demangle_java_sym(str, p + 1, buf + l1, len - l1, MODE_PREFIX); + if (!ptr) + goto error; + + return buf; +error: + free(buf); + return NULL; +} diff --git a/tools/perf/util/demangle-java.h b/tools/perf/util/demangle-java.h new file mode 100644 index 000000000000..a981c1f968fe --- /dev/null +++ b/tools/perf/util/demangle-java.h @@ -0,0 +1,10 @@ +#ifndef __PERF_DEMANGLE_JAVA +#define __PERF_DEMANGLE_JAVA 1 +/* + * demangle function flags + */ +#define JAVA_DEMANGLE_NORET 0x1 /* do not process return type */ + +char * java_demangle_sym(const char *str, int flags); + +#endif /* __PERF_DEMANGLE_JAVA */ diff --git a/tools/perf/util/symbol-elf.c b/tools/perf/util/symbol-elf.c index 562b8ebeae5b..b1dd68f358fc 100644 --- a/tools/perf/util/symbol-elf.c +++ b/tools/perf/util/symbol-elf.c @@ -6,6 +6,7 @@ #include #include "symbol.h" +#include "demangle-java.h" #include "machine.h" #include "vdso.h" #include @@ -1077,6 +1078,8 @@ new_symbol: demangle_flags = DMGL_PARAMS | DMGL_ANSI; demangled = bfd_demangle(NULL, elf_name, demangle_flags); + if (demangled == NULL) + demangled = java_demangle_sym(elf_name, JAVA_DEMANGLE_NORET); if (demangled != NULL) elf_name = demangled; } -- 2.20.1