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Message-ID: <20250430004128.474388-2-irogers@google.com>
Date: Tue, 29 Apr 2025 17:41:23 -0700
From: Ian Rogers <irogers@...gle.com>
To: Peter Zijlstra <peterz@...radead.org>, Ingo Molnar <mingo@...hat.com>,
Arnaldo Carvalho de Melo <acme@...nel.org>, Namhyung Kim <namhyung@...nel.org>,
Mark Rutland <mark.rutland@....com>,
Alexander Shishkin <alexander.shishkin@...ux.intel.com>, Jiri Olsa <jolsa@...nel.org>,
Adrian Hunter <adrian.hunter@...el.com>, Kan Liang <kan.liang@...ux.intel.com>,
Miguel Ojeda <ojeda@...nel.org>, Alex Gaynor <alex.gaynor@...il.com>,
Boqun Feng <boqun.feng@...il.com>, Gary Guo <gary@...yguo.net>,
"Björn Roy Baron" <bjorn3_gh@...tonmail.com>, Benno Lossin <benno.lossin@...ton.me>,
Andreas Hindborg <a.hindborg@...nel.org>, Alice Ryhl <aliceryhl@...gle.com>,
Trevor Gross <tmgross@...ch.edu>, Danilo Krummrich <dakr@...nel.org>,
Nathan Chancellor <nathan@...nel.org>, Nick Desaulniers <nick.desaulniers+lkml@...il.com>,
Bill Wendling <morbo@...gle.com>, Justin Stitt <justinstitt@...gle.com>,
James Clark <james.clark@...aro.org>, Howard Chu <howardchu95@...il.com>,
Jiapeng Chong <jiapeng.chong@...ux.alibaba.com>, Ravi Bangoria <ravi.bangoria@....com>,
"Masami Hiramatsu (Google)" <mhiramat@...nel.org>, Stephen Brennan <stephen.s.brennan@...cle.com>,
linux-kernel@...r.kernel.org, linux-perf-users@...r.kernel.org,
rust-for-linux@...r.kernel.org, llvm@...ts.linux.dev,
Daniel Xu <dxu@...uu.xyz>, Ariel Ben-Yehuda <ariel.byd@...il.com>
Cc: Ian Rogers <irogers@...gle.com>
Subject: [PATCH v2 1/6] perf demangle-rust: Add rustc-demangle C demangler
Imported at commit 80e40f57d99f ("add comment about finding latest
version of code") from:
https://github.com/rust-lang/rustc-demangle/blob/main/crates/native-c/src/demangle.c
https://github.com/rust-lang/rustc-demangle/blob/main/crates/native-c/include/demangle.h
There is discussion of this issue motivating the import in:
https://github.com/rust-lang/rust/issues/60705
https://lore.kernel.org/lkml/20250129193037.573431-1-irogers@google.com/
The SPDX lines reflect the dual license Apache-2 or MIT in:
https://github.com/rust-lang/rustc-demangle/blob/main/README.md
Following Migual Ojeda's suggestion comments were added on copyright
and keeping the code in sync with upstream.
The files are renamed as perf supports multiple demanglers and so
demangle as a name would be overloaded.
The work here was done by Ariel Ben-Yehuda <ariel.byd@...il.com> and I
am merely importing it as discussed in the rust-lang issue.
Signed-off-by: Ian Rogers <irogers@...gle.com>
---
tools/perf/util/demangle-rust-v0.c | 2042 ++++++++++++++++++++++++++++
tools/perf/util/demangle-rust-v0.h | 88 ++
2 files changed, 2130 insertions(+)
create mode 100644 tools/perf/util/demangle-rust-v0.c
create mode 100644 tools/perf/util/demangle-rust-v0.h
diff --git a/tools/perf/util/demangle-rust-v0.c b/tools/perf/util/demangle-rust-v0.c
new file mode 100644
index 000000000000..28e74ca0ff13
--- /dev/null
+++ b/tools/perf/util/demangle-rust-v0.c
@@ -0,0 +1,2042 @@
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+
+// The contents of this file come from the Rust rustc-demangle library, hosted
+// in the <https://github.com/rust-lang/rustc-demangle> repository, licensed
+// under "Apache-2.0 OR MIT". For copyright details, see
+// <https://github.com/rust-lang/rustc-demangle/blob/main/README.md>.
+// Please note that the file should be kept as close as possible to upstream.
+
+// Code for demangling Rust symbols. This code is mostly
+// a line-by-line translation of the Rust code in `rustc-demangle`.
+
+// you can find the latest version of this code in https://github.com/rust-lang/rustc-demangle
+
+#include <stdint.h>
+#include <stddef.h>
+#include <string.h>
+#include <stdbool.h>
+#include <sys/param.h>
+#include <stdio.h>
+
+#include "demangle-rust-v0.h"
+
+#if defined(__GNUC__) || defined(__clang__)
+#define NODISCARD __attribute__((warn_unused_result))
+#else
+#define NODISCARD
+#endif
+
+#define MAX_DEPTH 500
+
+typedef enum {
+ DemangleOk,
+ DemangleInvalid,
+ DemangleRecursed,
+ DemangleBug,
+} demangle_status;
+
+struct demangle_v0 {
+ const char *mangled;
+ size_t mangled_len;
+};
+
+struct demangle_legacy {
+ const char *mangled;
+ size_t mangled_len;
+ size_t elements;
+};
+
+// private version of memrchr to avoid _GNU_SOURCE
+static void *demangle_memrchr(const void *s, int c, size_t n) {
+ const uint8_t *s_ = s;
+ for (; n != 0; n--) {
+ if (s_[n-1] == c) {
+ return (void*)&s_[n-1];
+ }
+ }
+ return NULL;
+}
+
+
+static bool unicode_iscontrol(uint32_t ch) {
+ // this is *technically* a unicode table, but
+ // some unicode properties are simpler than you might think
+ return ch < 0x20 || (ch >= 0x7f && ch < 0xa0);
+}
+
+// "good enough" tables, the only consequence is that when printing
+// *constant strings*, some characters are printed as `\u{abcd}` rather than themselves.
+//
+// I'm leaving these here to allow easily replacing them with actual
+// tables if desired.
+static bool unicode_isprint(uint32_t ch) {
+ if (ch < 0x20) {
+ return false;
+ }
+ if (ch < 0x7f) {
+ return true;
+ }
+ return false;
+}
+
+static bool unicode_isgraphemextend(uint32_t ch) {
+ (void)ch;
+ return false;
+}
+
+static bool str_isascii(const char *s, size_t s_len) {
+ for (size_t i = 0; i < s_len; i++) {
+ if (s[i] & 0x80) {
+ return false;
+ }
+ }
+
+ return true;
+}
+
+typedef enum {
+ PunycodeOk,
+ PunycodeError
+} punycode_status;
+
+struct parser {
+ // the parser assumes that `sym` has a safe "terminating byte". It might be NUL,
+ // but it might also be something else if a symbol is "truncated".
+ const char *sym;
+ size_t sym_len;
+ size_t next;
+ uint32_t depth;
+};
+
+struct printer {
+ demangle_status status; // if status == 0 parser is valid
+ struct parser parser;
+ char *out; // NULL for no output [in which case out_len is not decremented]
+ size_t out_len;
+ uint32_t bound_lifetime_depth;
+ bool alternate;
+};
+
+static NODISCARD overflow_status printer_print_path(struct printer *printer, bool in_value);
+static NODISCARD overflow_status printer_print_type(struct printer *printer);
+static NODISCARD overflow_status printer_print_const(struct printer *printer, bool in_value);
+
+static NODISCARD demangle_status try_parse_path(struct parser *parser) {
+ struct printer printer = {
+ DemangleOk,
+ *parser,
+ NULL,
+ SIZE_MAX,
+ 0,
+ false
+ };
+ overflow_status ignore = printer_print_path(&printer, false); // can't fail since no output
+ (void)ignore;
+ *parser = printer.parser;
+ return printer.status;
+}
+
+NODISCARD static demangle_status rust_demangle_v0_demangle(const char *s, size_t s_len, struct demangle_v0 *res, const char **rest) {
+ if (s_len > strlen(s)) {
+ // s_len only exists to shorten the string, this is not a buffer API
+ return DemangleInvalid;
+ }
+
+ const char *inner;
+ size_t inner_len;
+ if (s_len >= 2 && !strncmp(s, "_R", strlen("_R"))) {
+ inner = s+2;
+ inner_len = s_len - 2;
+ } else if (s_len >= 1 && !strncmp(s, "R", strlen("R"))) {
+ // On Windows, dbghelp strips leading underscores, so we accept "R..."
+ // form too.
+ inner = s+1;
+ inner_len = s_len - 1;
+ } else if (s_len >= 3 && !strncmp(s, "__R", strlen("__R"))) {
+ // On OSX, symbols are prefixed with an extra _
+ inner = s+3;
+ inner_len = s_len - 3;
+ } else {
+ return DemangleInvalid;
+ }
+
+ // Paths always start with uppercase characters.
+ if (*inner < 'A' || *inner > 'Z') {
+ return DemangleInvalid;
+ }
+
+ if (!str_isascii(inner, inner_len)) {
+ return DemangleInvalid;
+ }
+
+ struct parser parser = { inner, inner_len, 0, 0 };
+
+ demangle_status status = try_parse_path(&parser);
+ if (status != DemangleOk) return status;
+ char next = parser.sym[parser.next];
+
+ // Instantiating crate (paths always start with uppercase characters).
+ if (parser.next < parser.sym_len && next >= 'A' && next <= 'Z') {
+ status = try_parse_path(&parser);
+ if (status != DemangleOk) return status;
+ }
+
+ res->mangled = inner;
+ res->mangled_len = inner_len;
+ if (rest) {
+ *rest = parser.sym + parser.next;
+ }
+
+ return DemangleOk;
+}
+
+// This might require `len` to be up to 3 characters bigger than the real output len in case of utf-8
+NODISCARD static overflow_status rust_demangle_v0_display_demangle(struct demangle_v0 res, char *out, size_t len, bool alternate) {
+ struct printer printer = {
+ DemangleOk,
+ {
+ res.mangled,
+ res.mangled_len,
+ 0,
+ 0
+ },
+ out,
+ len,
+ 0,
+ alternate
+ };
+ if (printer_print_path(&printer, true) == OverflowOverflow) {
+ return OverflowOverflow;
+ }
+ if (printer.out_len < OVERFLOW_MARGIN) {
+ return OverflowOverflow;
+ }
+ *printer.out = '\0';
+ return OverflowOk;
+}
+
+static size_t code_to_utf8(unsigned char *buffer, uint32_t code)
+{
+ if (code <= 0x7F) {
+ buffer[0] = code;
+ return 1;
+ }
+ if (code <= 0x7FF) {
+ buffer[0] = 0xC0 | (code >> 6); /* 110xxxxx */
+ buffer[1] = 0x80 | (code & 0x3F); /* 10xxxxxx */
+ return 2;
+ }
+ if (code <= 0xFFFF) {
+ buffer[0] = 0xE0 | (code >> 12); /* 1110xxxx */
+ buffer[1] = 0x80 | ((code >> 6) & 0x3F); /* 10xxxxxx */
+ buffer[2] = 0x80 | (code & 0x3F); /* 10xxxxxx */
+ return 3;
+ }
+ if (code <= 0x10FFFF) {
+ buffer[0] = 0xF0 | (code >> 18); /* 11110xxx */
+ buffer[1] = 0x80 | ((code >> 12) & 0x3F); /* 10xxxxxx */
+ buffer[2] = 0x80 | ((code >> 6) & 0x3F); /* 10xxxxxx */
+ buffer[3] = 0x80 | (code & 0x3F); /* 10xxxxxx */
+ return 4;
+ }
+ return 0;
+}
+
+
+// return length of char at byte, or SIZE_MAX if invalid. buf should have 4 valid characters
+static NODISCARD size_t utf8_next_char(uint8_t *s, uint32_t *ch) {
+ uint8_t byte = *s;
+ // UTF8-1 = %x00-7F
+ // UTF8-2 = %xC2-DF UTF8-tail
+ // UTF8-3 = %xE0 %xA0-BF UTF8-tail / %xE1-EC 2( UTF8-tail ) /
+ // %xED %x80-9F UTF8-tail / %xEE-EF 2( UTF8-tail )
+ // UTF8-4 = %xF0 %x90-BF 2( UTF8-tail ) / %xF1-F3 3( UTF8-tail ) /
+ // %xF4 %x80-8F 2( UTF8-tail )
+ if (byte < 0x80) {
+ *ch = byte;
+ return 1;
+ } else if (byte < 0xc2) {
+ return SIZE_MAX;
+ } else if (byte < 0xe0) {
+ if (s[1] >= 0x80 && s[1] < 0xc0) {
+ *ch = ((byte&0x1f)<<6) + (s[1] & 0x3f);
+ return 2;
+ }
+ return SIZE_MAX;
+ } if (byte < 0xf0) {
+ if (!(s[1] >= 0x80 && s[1] < 0xc0) || !(s[2] >= 0x80 && s[2] < 0xc0)) {
+ return SIZE_MAX; // basic validation
+ }
+ if (byte == 0xe0 && s[1] < 0xa0) {
+ return SIZE_MAX; // overshort
+ }
+ if (byte == 0xed && s[1] >= 0xa0) {
+ return SIZE_MAX; // surrogate
+ }
+ *ch = ((byte&0x0f)<<12) + ((s[1] & 0x3f)<<6) + (s[2] & 0x3f);
+ return 3;
+ } else if (byte < 0xf5) {
+ if (!(s[1] >= 0x80 && s[1] < 0xc0) || !(s[2] >= 0x80 && s[2] < 0xc0) || !(s[3] >= 0x80 && s[3] < 0xc0)) {
+ return SIZE_MAX; // basic validation
+ }
+ if (byte == 0xf0 && s[1] < 0x90) {
+ return SIZE_MAX; // overshort
+ }
+ if (byte == 0xf4 && s[1] >= 0x90) {
+ return SIZE_MAX; // over max
+ }
+ *ch = ((byte&0x07)<<18) + ((s[1] & 0x3f)<<12) + ((s[2] & 0x3f)<<6) + (s[3]&0x3f);
+ return 4;
+ } else {
+ return SIZE_MAX;
+ }
+}
+
+static NODISCARD bool validate_char(uint32_t n) {
+ return ((n ^ 0xd800) - 0x800) < 0x110000 - 0x800;
+}
+
+#define SMALL_PUNYCODE_LEN 128
+
+static NODISCARD punycode_status punycode_decode(const char *start, size_t ascii_len, const char *punycode_start, size_t punycode_len, uint32_t (*out_)[SMALL_PUNYCODE_LEN], size_t *out_len) {
+ uint32_t *out = *out_;
+
+ if (punycode_len == 0) {
+ return PunycodeError;
+ }
+
+ if (ascii_len > SMALL_PUNYCODE_LEN) {
+ return PunycodeError;
+ }
+ for (size_t i = 0; i < ascii_len; i++) {
+ out[i] = start[i];
+ }
+ size_t len = ascii_len;
+
+ size_t base = 36, t_min = 1, t_max = 26, skew = 38, damp = 700, bias = 72, i = 0, n = 0x80;
+ for (;;) {
+ size_t delta = 0, w = 1, k = 0;
+ for (;;) {
+ k += base;
+ size_t biased = k < bias ? 0 : k - bias;
+ size_t t = MIN(MAX(biased, t_min), t_max);
+ size_t d;
+ if (punycode_len == 0) {
+ return PunycodeError;
+ }
+ char nx = *punycode_start++;
+ punycode_len--;
+ if ('a' <= nx && nx <= 'z') {
+ d = nx - 'a';
+ } else if ('0' <= nx && nx <= '9') {
+ d = 26 + (nx - '0');
+ } else {
+ return PunycodeError;
+ }
+ if (w == 0 || d > SIZE_MAX / w || d*w > SIZE_MAX - delta) {
+ return PunycodeError;
+ }
+ delta += d * w;
+ if (d < t) {
+ break;
+ }
+ if (base < t || w == 0 || (base - t) > SIZE_MAX / w) {
+ return PunycodeError;
+ }
+ w *= (base - t);
+ }
+
+ len += 1;
+ if (i > SIZE_MAX - delta) {
+ return PunycodeError;
+ }
+ i += delta;
+ if (n > SIZE_MAX - i / len) {
+ return PunycodeError;
+ }
+ n += i / len;
+ i %= len;
+
+ // char validation
+ if (n > UINT32_MAX || !validate_char((uint32_t)n)) {
+ return PunycodeError;
+ }
+
+ // insert new character
+ if (len > SMALL_PUNYCODE_LEN) {
+ return PunycodeError;
+ }
+ memmove(out + i + 1, out + i, (len - i - 1) * sizeof(uint32_t));
+ out[i] = (uint32_t)n;
+
+ // start i index at incremented position
+ i++;
+
+ // If there are no more deltas, decoding is complete.
+ if (punycode_len == 0) {
+ *out_len = len;
+ return PunycodeOk;
+ }
+
+ // Perform bias adaptation.
+ delta /= damp;
+ damp = 2;
+
+ delta += delta / len;
+ k = 0;
+ while (delta > ((base - t_min) * t_max) / 2) {
+ delta /= base - t_min;
+ k += base;
+ }
+ bias = k + ((base - t_min + 1) * delta) / (delta + skew);
+ }
+}
+
+struct ident {
+ const char *ascii_start;
+ size_t ascii_len;
+ const char *punycode_start;
+ size_t punycode_len;
+};
+
+static NODISCARD overflow_status display_ident(const char *ascii_start, size_t ascii_len, const char *punycode_start, size_t punycode_len, uint8_t *out, size_t *out_len) {
+ uint32_t outbuf[SMALL_PUNYCODE_LEN];
+
+ size_t wide_len;
+ size_t out_buflen = *out_len;
+
+ if (punycode_len == 0) {
+ if (ascii_len > out_buflen) {
+ return OverflowOverflow;
+ }
+ memcpy(out, ascii_start, ascii_len);
+ *out_len = ascii_len;
+ } else if (punycode_decode(ascii_start, ascii_len, punycode_start, punycode_len, &outbuf, &wide_len) == PunycodeOk) {
+ size_t narrow_len = 0;
+ for (size_t i = 0; i < wide_len; i++) {
+ if (out_buflen - narrow_len < 4) {
+ return OverflowOverflow;
+ }
+ unsigned char *pos = &out[narrow_len];
+ narrow_len += code_to_utf8(pos, outbuf[i]);
+ }
+ *out_len = narrow_len;
+ } else {
+ size_t narrow_len = 0;
+ if (out_buflen < strlen("punycode{")) {
+ return OverflowOverflow;
+ }
+ memcpy(out, "punycode{", strlen("punycode{"));
+ narrow_len = strlen("punycode{");
+ if (ascii_len > 0) {
+ if (out_buflen - narrow_len < ascii_len || out_buflen - narrow_len - ascii_len < 1) {
+ return OverflowOverflow;
+ }
+ memcpy(out + narrow_len, ascii_start, ascii_len);
+ narrow_len += ascii_len;
+ out[narrow_len] = '-';
+ narrow_len++;
+ }
+ if (out_buflen - narrow_len < punycode_len || out_buflen - narrow_len - punycode_len < 1) {
+ return OverflowOverflow;
+ }
+ memcpy(out + narrow_len, punycode_start, punycode_len);
+ narrow_len += punycode_len;
+ out[narrow_len] = '}';
+ narrow_len++;
+ *out_len = narrow_len;
+ }
+
+ return OverflowOk;
+}
+
+static NODISCARD bool try_parse_uint(const char *buf, size_t len, uint64_t *result) {
+ size_t cur = 0;
+ for(;cur < len && buf[cur] == '0';cur++);
+ uint64_t result_val = 0;
+ if (len - cur > 16) return false;
+ for(;cur < len;cur++) {
+ char c = buf[cur];
+ result_val <<= 4;
+ if ('0' <= c && c <= '9') {
+ result_val += c - '0';
+ } else if ('a' <= c && c <= 'f') {
+ result_val += 10 + (c - 'a');
+ } else {
+ return false;
+ }
+ }
+ *result = result_val;
+ return true;
+}
+
+static NODISCARD bool dinibble2int(const char *buf, uint8_t *result) {
+ uint8_t result_val = 0;
+ for (int i = 0; i < 2; i++) {
+ char c = buf[i];
+ result_val <<= 4;
+ if ('0' <= c && c <= '9') {
+ result_val += c - '0';
+ } else if ('a' <= c && c <= 'f') {
+ result_val += 10 + (c - 'a');
+ } else {
+ return false;
+ }
+ }
+ *result = result_val;
+ return true;
+}
+
+
+typedef enum {
+ NtsOk = 0,
+ NtsOverflow = 1,
+ NtsInvalid = 2
+} nibbles_to_string_status;
+
+// '\u{10ffff}', +margin
+#define ESCAPED_SIZE 12
+
+static NODISCARD size_t char_to_string(uint32_t ch, uint8_t quote, bool first, char (*buf)[ESCAPED_SIZE]) {
+ // encode the character
+ char *escaped_buf = *buf;
+ escaped_buf[0] = '\\';
+ size_t escaped_len = 2;
+ switch (ch) {
+ case '\0':
+ escaped_buf[1] = '0';
+ break;
+ case '\t':
+ escaped_buf[1] = 't';
+ break;
+ case '\r':
+ escaped_buf[1] = 'r';
+ break;
+ case '\n':
+ escaped_buf[1] = 'n';
+ break;
+ case '\\':
+ escaped_buf[1] = '\\';
+ break;
+ default:
+ if (ch == quote) {
+ escaped_buf[1] = ch;
+ } else if (!unicode_isprint(ch) || (first && unicode_isgraphemextend(ch))) {
+ int hexlen = snprintf(escaped_buf, ESCAPED_SIZE, "\\u{%x}", (unsigned int)ch);
+ if (hexlen < 0) {
+ return 0; // (snprintf shouldn't fail!)
+ }
+ escaped_len = hexlen;
+ } else {
+ // printable character
+ escaped_buf[0] = ch;
+ escaped_len = 1;
+ }
+ break;
+ }
+
+ return escaped_len;
+}
+
+// convert nibbles to a single/double-quoted string
+static NODISCARD nibbles_to_string_status nibbles_to_string(const char *buf, size_t len, uint8_t *out, size_t *out_len) {
+ uint8_t quote = '"';
+ bool first = true;
+
+ if ((len % 2) != 0) {
+ return NtsInvalid; // odd number of nibbles
+ }
+
+ size_t cur_out_len = 0;
+
+ // write starting quote
+ if (out != NULL) {
+ cur_out_len = *out_len;
+ if (cur_out_len == 0) {
+ return NtsOverflow;
+ }
+ *out++ = quote;
+ cur_out_len--;
+ }
+
+ uint8_t conv_buf[4] = {0};
+ size_t conv_buf_len = 0;
+ while (len > 1 || conv_buf_len > 0) {
+ while (len > 1 && conv_buf_len < sizeof(conv_buf)) {
+ if (!dinibble2int(buf, &conv_buf[conv_buf_len])) {
+ return NtsInvalid;
+ }
+ conv_buf_len++;
+ buf += 2;
+ len -= 2;
+ }
+
+ // conv_buf is full here if possible, process 1 UTF-8 character
+ uint32_t ch = 0;
+ size_t consumed = utf8_next_char(conv_buf, &ch);
+ if (consumed > conv_buf_len) {
+ // either SIZE_MAX (invalid UTF-8) or finished input buffer and
+ // there are still bytes remaining, in both cases invalid
+ return NtsInvalid;
+ }
+
+ // "consume" the character
+ memmove(conv_buf, conv_buf+consumed, conv_buf_len-consumed);
+ conv_buf_len -= consumed;
+
+ char escaped_buf[ESCAPED_SIZE];
+ size_t escaped_len = char_to_string(ch, '"', first, &escaped_buf);
+ if (out != NULL) {
+ if (cur_out_len < escaped_len) {
+ return NtsOverflow;
+ }
+ memcpy(out, escaped_buf, escaped_len);
+ out += escaped_len;
+ cur_out_len -= escaped_len;
+ }
+ first = false;
+ }
+
+ // write ending quote
+ if (out != NULL) {
+ if (cur_out_len == 0) {
+ return NtsOverflow;
+ }
+ *out++ = quote;
+ cur_out_len--;
+ *out_len -= cur_out_len; // subtract remaining space to get used space
+ }
+
+ return NtsOk;
+}
+
+static const char* basic_type(uint8_t tag) {
+ switch(tag) {
+ case 'b':
+ return "bool";
+ case 'c':
+ return "char";
+ case 'e':
+ return "str";
+ case 'u':
+ return "()";
+ case 'a':
+ return "i8";
+ case 's':
+ return "i16";
+ case 'l':
+ return "i32";
+ case 'x':
+ return "i64";
+ case 'n':
+ return "i128";
+ case 'i':
+ return "isize";
+ case 'h':
+ return "u8";
+ case 't':
+ return "u16";
+ case 'm':
+ return "u32";
+ case 'y':
+ return "u64";
+ case 'o':
+ return "u128";
+ case 'j':
+ return "usize";
+ case 'f':
+ return "f32";
+ case 'd':
+ return "f64";
+ case 'z':
+ return "!";
+ case 'p':
+ return "_";
+ case 'v':
+ return "...";
+ default:
+ return NULL;
+ }
+}
+
+static NODISCARD demangle_status parser_push_depth(struct parser *parser) {
+ parser->depth++;
+ if (parser->depth > MAX_DEPTH) {
+ return DemangleRecursed;
+ } else {
+ return DemangleOk;
+ }
+}
+
+static demangle_status parser_pop_depth(struct parser *parser) {
+ parser->depth--;
+ return DemangleOk;
+}
+
+static uint8_t parser_peek(struct parser const *parser) {
+ if (parser->next == parser->sym_len) {
+ return 0; // add a "pseudo nul terminator" to avoid peeking past the end of a symbol
+ } else {
+ return parser->sym[parser->next];
+ }
+}
+
+static bool parser_eat(struct parser *parser, uint8_t ch) {
+ if (parser_peek(parser) == ch) {
+ if (ch != 0) { // safety: make sure we don't skip past the NUL terminator
+ parser->next++;
+ }
+ return true;
+ } else {
+ return false;
+ }
+}
+
+static uint8_t parser_next(struct parser *parser) {
+ // don't advance after end of input, and return an imaginary NUL terminator
+ if (parser->next == parser->sym_len) {
+ return 0;
+ } else {
+ return parser->sym[parser->next++];
+ }
+}
+
+static NODISCARD demangle_status parser_ch(struct parser *parser, uint8_t *next) {
+ // don't advance after end of input
+ if (parser->next == parser->sym_len) {
+ return DemangleInvalid;
+ } else {
+ *next = parser->sym[parser->next++];
+ return DemangleOk;
+ }
+}
+
+struct buf {
+ const char *start;
+ size_t len;
+};
+
+static NODISCARD demangle_status parser_hex_nibbles(struct parser *parser, struct buf *buf) {
+ size_t start = parser->next;
+ for (;;) {
+ uint8_t ch = parser_next(parser);
+ if (ch == '_') {
+ break;
+ }
+ if (!(('0' <= ch && ch <= '9') || ('a' <= ch && ch <= 'f'))) {
+ return DemangleInvalid;
+ }
+ }
+ buf->start = parser->sym + start;
+ buf->len = parser->next - start - 1; // skip final _
+ return DemangleOk;
+}
+
+static NODISCARD demangle_status parser_digit_10(struct parser *parser, uint8_t *out) {
+ uint8_t ch = parser_peek(parser);
+ if ('0' <= ch && ch <= '9') {
+ *out = ch - '0';
+ parser->next++;
+ return DemangleOk;
+ } else {
+ return DemangleInvalid;
+ }
+}
+
+static NODISCARD demangle_status parser_digit_62(struct parser *parser, uint64_t *out) {
+ uint8_t ch = parser_peek(parser);
+ if ('0' <= ch && ch <= '9') {
+ *out = ch - '0';
+ parser->next++;
+ return DemangleOk;
+ } else if ('a' <= ch && ch <= 'z') {
+ *out = 10 + (ch - 'a');
+ parser->next++;
+ return DemangleOk;
+ } else if ('A' <= ch && ch <= 'Z') {
+ *out = 10 + 26 + (ch - 'A');
+ parser->next++;
+ return DemangleOk;
+ } else {
+ return DemangleInvalid;
+ }
+}
+
+static NODISCARD demangle_status parser_integer_62(struct parser *parser, uint64_t *out) {
+ if (parser_eat(parser, '_')) {
+ *out = 0;
+ return DemangleOk;
+ }
+
+ uint64_t x = 0;
+ demangle_status status;
+ while (!parser_eat(parser, '_')) {
+ uint64_t d;
+ if ((status = parser_digit_62(parser, &d)) != DemangleOk) {
+ return status;
+ }
+ if (x > UINT64_MAX / 62) {
+ return DemangleInvalid;
+ }
+ x *= 62;
+ if (x > UINT64_MAX - d) {
+ return DemangleInvalid;
+ }
+ x += d;
+ }
+ if (x == UINT64_MAX) {
+ return DemangleInvalid;
+ }
+ *out = x + 1;
+ return DemangleOk;
+}
+
+static NODISCARD demangle_status parser_opt_integer_62(struct parser *parser, uint8_t tag, uint64_t *out) {
+ if (!parser_eat(parser, tag)) {
+ *out = 0;
+ return DemangleOk;
+ }
+
+ demangle_status status;
+ if ((status = parser_integer_62(parser, out)) != DemangleOk) {
+ return status;
+ }
+ if (*out == UINT64_MAX) {
+ return DemangleInvalid;
+ }
+ *out = *out + 1;
+ return DemangleOk;
+}
+
+static NODISCARD demangle_status parser_disambiguator(struct parser *parser, uint64_t *out) {
+ return parser_opt_integer_62(parser, 's', out);
+}
+
+typedef uint8_t parser_namespace_type;
+
+static NODISCARD demangle_status parser_namespace(struct parser *parser, parser_namespace_type *out) {
+ uint8_t next = parser_next(parser);
+ if ('A' <= next && next <= 'Z') {
+ *out = next;
+ return DemangleOk;
+ } else if ('a' <= next && next <= 'z') {
+ *out = 0;
+ return DemangleOk;
+ } else {
+ return DemangleInvalid;
+ }
+}
+
+static NODISCARD demangle_status parser_backref(struct parser *parser, struct parser *out) {
+ size_t start = parser->next;
+ if (start == 0) {
+ return DemangleBug;
+ }
+ size_t s_start = start - 1;
+ uint64_t i;
+ demangle_status status = parser_integer_62(parser, &i);
+ if (status != DemangleOk) {
+ return status;
+ }
+ if (i >= s_start) {
+ return DemangleInvalid;
+ }
+ struct parser res = {
+ .sym = parser->sym,
+ .sym_len = parser->sym_len,
+ .next = (size_t)i,
+ .depth = parser->depth
+ };
+ status = parser_push_depth(&res);
+ if (status != DemangleOk) {
+ return status;
+ }
+ *out = res;
+ return DemangleOk;
+}
+
+static NODISCARD demangle_status parser_ident(struct parser *parser, struct ident *out) {
+ bool is_punycode = parser_eat(parser, 'u');
+ size_t len;
+ uint8_t d;
+ demangle_status status = parser_digit_10(parser, &d);
+ len = d;
+ if (status != DemangleOk) {
+ return status;
+ }
+ if (len) {
+ for (;;) {
+ status = parser_digit_10(parser, &d);
+ if (status != DemangleOk) {
+ break;
+ }
+ if (len > SIZE_MAX / 10) {
+ return DemangleInvalid;
+ }
+ len *= 10;
+ if (len > SIZE_MAX - d) {
+ return DemangleInvalid;
+ }
+ len += d;
+ }
+ }
+
+ // Skip past the optional `_` separator.
+ parser_eat(parser, '_');
+
+ size_t start = parser->next;
+ if (parser->sym_len - parser->next < len) {
+ return DemangleInvalid;
+ }
+ parser->next += len;
+
+ const char *ident = &parser->sym[start];
+
+ if (is_punycode) {
+ const char *underscore = demangle_memrchr(ident, '_', (size_t)len);
+ if (underscore == NULL) {
+ *out = (struct ident){
+ .ascii_start="",
+ .ascii_len=0,
+ .punycode_start=ident,
+ .punycode_len=len
+ };
+ } else {
+ size_t ascii_len = underscore - ident;
+ // ascii_len <= len - 1 since `_` is in the first len bytes
+ size_t punycode_len = len - 1 - ascii_len;
+ *out = (struct ident){
+ .ascii_start=ident,
+ .ascii_len=ascii_len,
+ .punycode_start=underscore + 1,
+ .punycode_len=punycode_len
+ };
+ }
+ if (out->punycode_len == 0) {
+ return DemangleInvalid;
+ }
+ return DemangleOk;
+ } else {
+ *out = (struct ident) {
+ .ascii_start=ident,
+ .ascii_len=(size_t)len,
+ .punycode_start="",
+ .punycode_len=0,
+ };
+ return DemangleOk;
+ }
+}
+
+#define INVALID_SYNTAX "{invalid syntax}"
+
+static const char *demangle_error_message(demangle_status status) {
+ switch (status) {
+ case DemangleInvalid:
+ return INVALID_SYNTAX;
+ case DemangleBug:
+ return "{bug}";
+ case DemangleRecursed:
+ return "{recursion limit reached}";
+ default:
+ return "{unknown error}";
+ }
+}
+
+#define PRINT(print_fn) \
+ do { \
+ if ((print_fn) == OverflowOverflow) { \
+ return OverflowOverflow; \
+ } \
+ } while(0)
+
+#define PRINT_CH(printer, s) PRINT(printer_print_ch((printer), (s)))
+#define PRINT_STR(printer, s) PRINT(printer_print_str((printer), (s)))
+#define PRINT_U64(printer, s) PRINT(printer_print_u64((printer), (s)))
+#define PRINT_IDENT(printer, s) PRINT(printer_print_ident((printer), (s)))
+
+#define INVALID(printer) \
+ do { \
+ PRINT_STR((printer), INVALID_SYNTAX); \
+ (printer)->status = DemangleInvalid; \
+ return OverflowOk; \
+ } while(0)
+
+#define PARSE(printer, method, ...) \
+ do { \
+ if ((printer)->status != DemangleOk) { \
+ PRINT_STR((printer), "?"); \
+ return OverflowOk; \
+ } else { \
+ demangle_status _parse_status = method(&(printer)->parser, ## __VA_ARGS__); \
+ if (_parse_status != DemangleOk) { \
+ PRINT_STR((printer), demangle_error_message(_parse_status)); \
+ (printer)->status = _parse_status; \
+ return OverflowOk; \
+ } \
+ } \
+ } while(0)
+
+#define PRINT_SEP_LIST(printer, body, sep) \
+ do { \
+ size_t _sep_list_i; \
+ PRINT_SEP_LIST_COUNT(printer, _sep_list_i, body, sep); \
+ } while(0)
+
+#define PRINT_SEP_LIST_COUNT(printer, count, body, sep) \
+ do { \
+ count = 0; \
+ while ((printer)->status == DemangleOk && !printer_eat((printer), 'E')) { \
+ if (count > 0) { PRINT_STR(printer, sep); } \
+ body; \
+ count++; \
+ } \
+ } while(0)
+
+static bool printer_eat(struct printer *printer, uint8_t b) {
+ if (printer->status != DemangleOk) {
+ return false;
+ }
+
+ return parser_eat(&printer->parser, b);
+}
+
+static void printer_pop_depth(struct printer *printer) {
+ if (printer->status == DemangleOk) {
+ parser_pop_depth(&printer->parser);
+ }
+}
+
+static NODISCARD overflow_status printer_print_buf(struct printer *printer, const char *start, size_t len) {
+ if (printer->out == NULL) {
+ return OverflowOk;
+ }
+ if (printer->out_len < len) {
+ return OverflowOverflow;
+ }
+
+ memcpy(printer->out, start, len);
+ printer->out += len;
+ printer->out_len -= len;
+ return OverflowOk;
+}
+
+static NODISCARD overflow_status printer_print_str(struct printer *printer, const char *buf) {
+ return printer_print_buf(printer, buf, strlen(buf));
+}
+
+static NODISCARD overflow_status printer_print_ch(struct printer *printer, char ch) {
+ return printer_print_buf(printer, &ch, 1);
+}
+
+static NODISCARD overflow_status printer_print_u64(struct printer *printer, uint64_t n) {
+ char buf[32] = {0};
+ sprintf(buf, "%llu", (unsigned long long)n); // printing uint64 uses 21 < 32 chars
+ return printer_print_str(printer, buf);
+}
+
+static NODISCARD overflow_status printer_print_ident(struct printer *printer, struct ident *ident) {
+ if (printer->out == NULL) {
+ return OverflowOk;
+ }
+
+ size_t out_len = printer->out_len;
+ overflow_status status;
+ if ((status = display_ident(ident->ascii_start, ident->ascii_len, ident->punycode_start, ident->punycode_len, (uint8_t*)printer->out, &out_len)) != OverflowOk) {
+ return status;
+ }
+ printer->out += out_len;
+ printer->out_len -= out_len;
+ return OverflowOk;
+}
+
+typedef overflow_status (*printer_fn)(struct printer *printer);
+typedef overflow_status (*backref_fn)(struct printer *printer, bool *arg);
+
+static NODISCARD overflow_status printer_print_backref(struct printer *printer, backref_fn func, bool *arg) {
+ struct parser backref;
+ PARSE(printer, parser_backref, &backref);
+
+ if (printer->out == NULL) {
+ return OverflowOk;
+ }
+
+ struct parser orig_parser = printer->parser;
+ demangle_status orig_status = printer->status; // fixme not sure this is needed match for Ok on the Rust side
+ printer->parser = backref;
+ printer->status = DemangleOk;
+ overflow_status status = func(printer, arg);
+ printer->parser = orig_parser;
+ printer->status = orig_status;
+
+ return status;
+}
+
+static NODISCARD overflow_status printer_print_lifetime_from_index(struct printer *printer, uint64_t lt) {
+ // Bound lifetimes aren't tracked when skipping printing.
+ if (printer->out == NULL) {
+ return OverflowOk;
+ }
+
+ PRINT_STR(printer, "'");
+ if (lt == 0) {
+ PRINT_STR(printer, "_");
+ return OverflowOk;
+ }
+
+ if (printer->bound_lifetime_depth < lt) {
+ INVALID(printer);
+ } else {
+ uint64_t depth = printer->bound_lifetime_depth - lt;
+ if (depth < 26) {
+ PRINT_CH(printer, 'a' + depth);
+ } else {
+ PRINT_STR(printer, "_");
+ PRINT_U64(printer, depth);
+ }
+
+ return OverflowOk;
+ }
+}
+
+static NODISCARD overflow_status printer_in_binder(struct printer *printer, printer_fn func) {
+ uint64_t bound_lifetimes;
+ PARSE(printer, parser_opt_integer_62, 'G', &bound_lifetimes);
+
+ // Don't track bound lifetimes when skipping printing.
+ if (printer->out == NULL) {
+ return func(printer);
+ }
+
+ if (bound_lifetimes > 0) {
+ PRINT_STR(printer, "for<");
+ for (uint64_t i = 0; i < bound_lifetimes; i++) {
+ if (i > 0) {
+ PRINT_STR(printer, ", ");
+ }
+ printer->bound_lifetime_depth++;
+ PRINT(printer_print_lifetime_from_index(printer, 1));
+ }
+ PRINT_STR(printer, "> ");
+ }
+
+ overflow_status r = func(printer);
+ printer->bound_lifetime_depth -= bound_lifetimes;
+
+ return r;
+}
+
+static NODISCARD overflow_status printer_print_generic_arg(struct printer *printer) {
+ if (printer_eat(printer, 'L')) {
+ uint64_t lt;
+ PARSE(printer, parser_integer_62, <);
+ return printer_print_lifetime_from_index(printer, lt);
+ } else if (printer_eat(printer, 'K')) {
+ return printer_print_const(printer, false);
+ } else {
+ return printer_print_type(printer);
+ }
+}
+
+static NODISCARD overflow_status printer_print_generic_args(struct printer *printer) {
+ PRINT_STR(printer, "<");
+ PRINT_SEP_LIST(printer, PRINT(printer_print_generic_arg(printer)), ", ");
+ PRINT_STR(printer, ">");
+ return OverflowOk;
+}
+
+static NODISCARD overflow_status printer_print_path_out_of_value(struct printer *printer, bool *_arg) {
+ (void)_arg;
+ return printer_print_path(printer, false);
+}
+
+static NODISCARD overflow_status printer_print_path_in_value(struct printer *printer, bool *_arg) {
+ (void)_arg;
+ return printer_print_path(printer, true);
+}
+
+static NODISCARD overflow_status printer_print_path(struct printer *printer, bool in_value) {
+ PARSE(printer, parser_push_depth);
+ uint8_t tag;
+ PARSE(printer, parser_ch, &tag);
+
+ overflow_status st;
+ uint64_t dis;
+ struct ident name;
+ parser_namespace_type ns;
+ char *orig_out;
+
+ switch(tag) {
+ case 'C':
+ PARSE(printer, parser_disambiguator, &dis);
+ PARSE(printer, parser_ident, &name);
+
+ PRINT_IDENT(printer, &name);
+
+ if (printer->out != NULL && !printer->alternate && dis != 0) {
+ PRINT_STR(printer, "[");
+ char buf[24] = {0};
+ sprintf(buf, "%llx", (unsigned long long)dis);
+ PRINT_STR(printer, buf);
+ PRINT_STR(printer, "]");
+ }
+ break;
+ case 'N':
+ PARSE(printer, parser_namespace, &ns);
+ if ((st = printer_print_path(printer, in_value)) != OverflowOk) {
+ return st;
+ }
+
+ // HACK(eddyb) if the parser is already marked as having errored,
+ // `parse!` below will print a `?` without its preceding `::`
+ // (because printing the `::` is skipped in certain conditions,
+ // i.e. a lowercase namespace with an empty identifier),
+ // so in order to get `::?`, the `::` has to be printed here.
+ if (printer->status != DemangleOk) {
+ PRINT_STR(printer, "::");
+ }
+
+ PARSE(printer, parser_disambiguator, &dis);
+ PARSE(printer, parser_ident, &name);
+ // Special namespace, like closures and shims
+ if (ns) {
+ PRINT_STR(printer, "::{");
+ if (ns == 'C') {
+ PRINT_STR(printer, "closure");
+ } else if (ns == 'S') {
+ PRINT_STR(printer, "shim");
+ } else {
+ PRINT_CH(printer, ns);
+ }
+ if (name.ascii_len != 0 || name.punycode_len != 0) {
+ PRINT_STR(printer, ":");
+ PRINT_IDENT(printer, &name);
+ }
+ PRINT_STR(printer, "#");
+ PRINT_U64(printer, dis);
+ PRINT_STR(printer, "}");
+ } else {
+ // Implementation-specific/unspecified namespaces
+ if (name.ascii_len != 0 || name.punycode_len != 0) {
+ PRINT_STR(printer, "::");
+ PRINT_IDENT(printer, &name);
+ }
+ }
+ break;
+ case 'M':
+ case 'X':
+ // for impls, ignore the impls own path
+ PARSE(printer, parser_disambiguator, &dis);
+ orig_out = printer->out;
+ printer->out = NULL;
+ PRINT(printer_print_path(printer, false));
+ printer->out = orig_out;
+
+ // fallthru
+ case 'Y':
+ PRINT_STR(printer, "<");
+ PRINT(printer_print_type(printer));
+ if (tag != 'M') {
+ PRINT_STR(printer, " as ");
+ PRINT(printer_print_path(printer, false));
+ }
+ PRINT_STR(printer, ">");
+ break;
+ case 'I':
+ PRINT(printer_print_path(printer, in_value));
+ if (in_value) {
+ PRINT_STR(printer, "::");
+ }
+ PRINT(printer_print_generic_args(printer));
+ break;
+ case 'B':
+ PRINT(printer_print_backref(printer, in_value ? printer_print_path_in_value : printer_print_path_out_of_value, NULL));
+ break;
+ default:
+ INVALID(printer);
+ break;
+ }
+
+ printer_pop_depth(printer);
+ return OverflowOk;
+}
+
+static NODISCARD overflow_status printer_print_const_uint(struct printer *printer, uint8_t tag) {
+ struct buf hex;
+ PARSE(printer, parser_hex_nibbles, &hex);
+
+ uint64_t val;
+ if (try_parse_uint(hex.start, hex.len, &val)) {
+ PRINT_U64(printer, val);
+ } else {
+ PRINT_STR(printer, "0x");
+ PRINT(printer_print_buf(printer, hex.start, hex.len));
+ }
+
+ if (printer->out != NULL && !printer->alternate) {
+ const char *ty = basic_type(tag);
+ if (/* safety */ ty != NULL) {
+ PRINT_STR(printer, ty);
+ }
+ }
+
+ return OverflowOk;
+}
+
+static NODISCARD overflow_status printer_print_const_str_literal(struct printer *printer) {
+ struct buf hex;
+ PARSE(printer, parser_hex_nibbles, &hex);
+
+ size_t out_len = SIZE_MAX;
+ nibbles_to_string_status nts_status = nibbles_to_string(hex.start, hex.len, NULL, &out_len);
+ switch (nts_status) {
+ case NtsOk:
+ if (printer->out != NULL) {
+ out_len = printer->out_len;
+ nts_status = nibbles_to_string(hex.start, hex.len, (uint8_t*)printer->out, &out_len);
+ if (nts_status != NtsOk) {
+ return OverflowOverflow;
+ }
+ printer->out += out_len;
+ printer->out_len -= out_len;
+ }
+ return OverflowOk;
+ case NtsOverflow:
+ // technically if there is a string of size `SIZE_MAX/6` whose escaped version overflows
+ // SIZE_MAX but has an invalid char, this will be a "fake" overflow. In practice,
+ // that is not going to happen and a fuzzer will not generate strings of this length.
+ return OverflowOverflow;
+ case NtsInvalid:
+ default:
+ INVALID(printer);
+ }
+}
+
+static NODISCARD overflow_status printer_print_const_struct(struct printer *printer) {
+ uint64_t dis;
+ struct ident name;
+ PARSE(printer, parser_disambiguator, &dis);
+ PARSE(printer, parser_ident, &name);
+ PRINT_IDENT(printer, &name);
+ PRINT_STR(printer, ": ");
+ return printer_print_const(printer, true);
+}
+
+static NODISCARD overflow_status printer_print_const_out_of_value(struct printer *printer, bool *_arg) {
+ (void)_arg;
+ return printer_print_const(printer, false);
+}
+
+static NODISCARD overflow_status printer_print_const_in_value(struct printer *printer, bool *_arg) {
+ (void)_arg;
+ return printer_print_const(printer, true);
+}
+
+static NODISCARD overflow_status printer_print_const(struct printer *printer, bool in_value) {
+ uint8_t tag;
+
+ PARSE(printer, parser_ch, &tag);
+ PARSE(printer, parser_push_depth);
+
+ struct buf hex;
+ uint64_t val;
+ size_t count;
+
+ bool opened_brace = false;
+#define OPEN_BRACE_IF_OUTSIDE_EXPR \
+ do { if (!in_value) { \
+ opened_brace = true; \
+ PRINT_STR(printer, "{"); \
+ } } while(0)
+
+ switch(tag) {
+ case 'p':
+ PRINT_STR(printer, "_");
+ break;
+ // Primitive leaves with hex-encoded values (see `basic_type`).
+ case 'a':
+ case 's':
+ case 'l':
+ case 'x':
+ case 'n':
+ case 'i':
+ if (printer_eat(printer, 'n')) {
+ PRINT_STR(printer, "-");
+ }
+ /* fallthrough */
+ case 'h':
+ case 't':
+ case 'm':
+ case 'y':
+ case 'o':
+ case 'j':
+ PRINT(printer_print_const_uint(printer, tag));
+ break;
+ case 'b':
+ PARSE(printer, parser_hex_nibbles, &hex);
+ if (try_parse_uint(hex.start, hex.len, &val)) {
+ if (val == 0) {
+ PRINT_STR(printer, "false");
+ } else if (val == 1) {
+ PRINT_STR(printer, "true");
+ } else {
+ INVALID(printer);
+ }
+ } else {
+ INVALID(printer);
+ }
+ break;
+ case 'c':
+ PARSE(printer, parser_hex_nibbles, &hex);
+ if (try_parse_uint(hex.start, hex.len, &val)
+ && val < UINT32_MAX
+ && validate_char((uint32_t)val))
+ {
+ char escaped_buf[ESCAPED_SIZE];
+ size_t escaped_size = char_to_string((uint32_t)val, '\'', true, &escaped_buf);
+
+ PRINT_STR(printer, "'");
+ PRINT(printer_print_buf(printer, escaped_buf, escaped_size));
+ PRINT_STR(printer, "'");
+ } else {
+ INVALID(printer);
+ }
+ break;
+ case 'e':
+ OPEN_BRACE_IF_OUTSIDE_EXPR;
+ PRINT_STR(printer, "*");
+ PRINT(printer_print_const_str_literal(printer));
+ break;
+ case 'R':
+ case 'Q':
+ if (tag == 'R' && printer_eat(printer, 'e')) {
+ PRINT(printer_print_const_str_literal(printer));
+ } else {
+ OPEN_BRACE_IF_OUTSIDE_EXPR;
+ PRINT_STR(printer, "&");
+ if (tag != 'R') {
+ PRINT_STR(printer, "mut ");
+ }
+ PRINT(printer_print_const(printer, true));
+ }
+ break;
+ case 'A':
+ OPEN_BRACE_IF_OUTSIDE_EXPR;
+ PRINT_STR(printer, "[");
+ PRINT_SEP_LIST(printer, PRINT(printer_print_const(printer, true)), ", ");
+ PRINT_STR(printer, "]");
+ break;
+ case 'T':
+ OPEN_BRACE_IF_OUTSIDE_EXPR;
+ PRINT_STR(printer, "(");
+ PRINT_SEP_LIST_COUNT(printer, count, PRINT(printer_print_const(printer, true)), ", ");
+ if (count == 1) {
+ PRINT_STR(printer, ",");
+ }
+ PRINT_STR(printer, ")");
+ break;
+ case 'V':
+ OPEN_BRACE_IF_OUTSIDE_EXPR;
+ PRINT(printer_print_path(printer, true));
+ PARSE(printer, parser_ch, &tag);
+ switch(tag) {
+ case 'U':
+ break;
+ case 'T':
+ PRINT_STR(printer, "(");
+ PRINT_SEP_LIST(printer, PRINT(printer_print_const(printer, true)), ", ");
+ PRINT_STR(printer, ")");
+ break;
+ case 'S':
+ PRINT_STR(printer, " { ");
+ PRINT_SEP_LIST(printer, PRINT(printer_print_const_struct(printer)), ", ");
+ PRINT_STR(printer, " }");
+ break;
+ default:
+ INVALID(printer);
+ }
+ break;
+ case 'B':
+ PRINT(printer_print_backref(printer, in_value ? printer_print_const_in_value : printer_print_const_out_of_value, NULL));
+ break;
+ default:
+ INVALID(printer);
+ }
+#undef OPEN_BRACE_IF_OUTSIDE_EXPR
+
+ if (opened_brace) {
+ PRINT_STR(printer, "}");
+ }
+ printer_pop_depth(printer);
+
+ return OverflowOk;
+}
+
+/// A trait in a trait object may have some "existential projections"
+/// (i.e. associated type bindings) after it, which should be printed
+/// in the `<...>` of the trait, e.g. `dyn Trait<T, U, Assoc=X>`.
+/// To this end, this method will keep the `<...>` of an 'I' path
+/// open, by omitting the `>`, and return `Ok(true)` in that case.
+static NODISCARD overflow_status printer_print_maybe_open_generics(struct printer *printer, bool *open) {
+ if (printer_eat(printer, 'B')) {
+ // NOTE(eddyb) the closure may not run if printing is being skipped,
+ // but in that case the returned boolean doesn't matter.
+ *open = false;
+ return printer_print_backref(printer, printer_print_maybe_open_generics, open);
+ } else if(printer_eat(printer, 'I')) {
+ PRINT(printer_print_path(printer, false));
+ PRINT_STR(printer, "<");
+ PRINT_SEP_LIST(printer, PRINT(printer_print_generic_arg(printer)), ", ");
+ *open = true;
+ return OverflowOk;
+ } else {
+ PRINT(printer_print_path(printer, false));
+ *open = false;
+ return OverflowOk;
+ }
+}
+
+static NODISCARD overflow_status printer_print_dyn_trait(struct printer *printer) {
+ bool open;
+ PRINT(printer_print_maybe_open_generics(printer, &open));
+
+ while (printer_eat(printer, 'p')) {
+ if (!open) {
+ PRINT_STR(printer, "<");
+ open = true;
+ } else {
+ PRINT_STR(printer, ", ");
+ }
+
+ struct ident name;
+ PARSE(printer, parser_ident, &name);
+
+ PRINT_IDENT(printer, &name);
+ PRINT_STR(printer, " = ");
+ PRINT(printer_print_type(printer));
+ }
+
+ if (open) {
+ PRINT_STR(printer, ">");
+ }
+
+ return OverflowOk;
+}
+
+static NODISCARD overflow_status printer_print_object_bounds(struct printer *printer) {
+ PRINT_SEP_LIST(printer, PRINT(printer_print_dyn_trait(printer)), " + ");
+ return OverflowOk;
+}
+
+static NODISCARD overflow_status printer_print_function_type(struct printer *printer) {
+ bool is_unsafe = printer_eat(printer, 'U');
+ const char *abi;
+ size_t abi_len;
+ if (printer_eat(printer, 'K')) {
+ if (printer_eat(printer, 'C')) {
+ abi = "C";
+ abi_len = 1;
+ } else {
+ struct ident abi_ident;
+ PARSE(printer, parser_ident, &abi_ident);
+ if (abi_ident.ascii_len == 0 || abi_ident.punycode_len != 0) {
+ INVALID(printer);
+ }
+ abi = abi_ident.ascii_start;
+ abi_len = abi_ident.ascii_len;
+ }
+ } else {
+ abi = NULL;
+ abi_len = 0;
+ }
+
+ if (is_unsafe) {
+ PRINT_STR(printer, "unsafe ");
+ }
+
+ if (abi != NULL) {
+ PRINT_STR(printer, "extern \"");
+
+ // replace _ with -
+ while (abi_len > 0) {
+ const char *minus = memchr(abi, '_', abi_len);
+ if (minus == NULL) {
+ PRINT(printer_print_buf(printer, (const char*)abi, abi_len));
+ break;
+ } else {
+ size_t space_to_minus = minus - abi;
+ PRINT(printer_print_buf(printer, (const char*)abi, space_to_minus));
+ PRINT_STR(printer, "-");
+ abi = minus + 1;
+ abi_len -= (space_to_minus + 1);
+ }
+ }
+
+ PRINT_STR(printer, "\" ");
+ }
+
+ PRINT_STR(printer, "fn(");
+ PRINT_SEP_LIST(printer, PRINT(printer_print_type(printer)), ", ");
+ PRINT_STR(printer, ")");
+
+ if (printer_eat(printer, 'u')) {
+ // Skip printing the return type if it's 'u', i.e. `()`.
+ } else {
+ PRINT_STR(printer, " -> ");
+ PRINT(printer_print_type(printer));
+ }
+
+ return OverflowOk;
+}
+
+static NODISCARD overflow_status printer_print_type_backref(struct printer *printer, bool *_arg) {
+ (void)_arg;
+ return printer_print_type(printer);
+}
+
+static NODISCARD overflow_status printer_print_type(struct printer *printer) {
+ uint8_t tag;
+ PARSE(printer, parser_ch, &tag);
+
+ const char *basic_ty = basic_type(tag);
+ if (basic_ty) {
+ return printer_print_str(printer, basic_ty);
+ }
+
+ uint64_t count;
+ uint64_t lt;
+
+ PARSE(printer, parser_push_depth);
+ switch (tag) {
+ case 'R':
+ case 'Q':
+ PRINT_STR(printer, "&");
+ if (printer_eat(printer, 'L')) {
+ PARSE(printer, parser_integer_62, <);
+ if (lt != 0) {
+ PRINT(printer_print_lifetime_from_index(printer, lt));
+ PRINT_STR(printer, " ");
+ }
+ }
+ if (tag != 'R') {
+ PRINT_STR(printer, "mut ");
+ }
+ PRINT(printer_print_type(printer));
+ break;
+ case 'P':
+ case 'O':
+ PRINT_STR(printer, "*");
+ if (tag != 'P') {
+ PRINT_STR(printer, "mut ");
+ } else {
+ PRINT_STR(printer, "const ");
+ }
+ PRINT(printer_print_type(printer));
+ break;
+ case 'A':
+ case 'S':
+ PRINT_STR(printer, "[");
+ PRINT(printer_print_type(printer));
+ if (tag == 'A') {
+ PRINT_STR(printer, "; ");
+ PRINT(printer_print_const(printer, true));
+ }
+ PRINT_STR(printer, "]");
+ break;
+ case 'T':
+ PRINT_STR(printer, "(");
+ PRINT_SEP_LIST_COUNT(printer, count, PRINT(printer_print_type(printer)), ", ");
+ if (count == 1) {
+ PRINT_STR(printer, ",");
+ }
+ PRINT_STR(printer, ")");
+ break;
+ case 'F':
+ PRINT(printer_in_binder(printer, printer_print_function_type));
+ break;
+ case 'D':
+ PRINT_STR(printer, "dyn ");
+ PRINT(printer_in_binder(printer, printer_print_object_bounds));
+
+ if (!printer_eat(printer, 'L')) {
+ INVALID(printer);
+ }
+ PARSE(printer, parser_integer_62, <);
+
+ if (lt != 0) {
+ PRINT_STR(printer, " + ");
+ PRINT(printer_print_lifetime_from_index(printer, lt));
+ }
+ break;
+ case 'B':
+ PRINT(printer_print_backref(printer, printer_print_type_backref, NULL));
+ break;
+ default:
+ // Go back to the tag, so `print_path` also sees it.
+ if (printer->status == DemangleOk && /* safety */ printer->parser.next > 0) {
+ printer->parser.next--;
+ }
+ PRINT(printer_print_path(printer, false));
+ }
+
+ printer_pop_depth(printer);
+ return OverflowOk;
+}
+
+NODISCARD static demangle_status rust_demangle_legacy_demangle(const char *s, size_t s_len, struct demangle_legacy *res, const char **rest)
+{
+ if (s_len > strlen(s)) {
+ // s_len only exists to shorten the string, this is not a buffer API
+ return DemangleInvalid;
+ }
+
+ const char *inner;
+ size_t inner_len;
+ if (s_len >= 3 && !strncmp(s, "_ZN", 3)) {
+ inner = s + 3;
+ inner_len = s_len - 3;
+ } else if (s_len >= 2 && !strncmp(s, "ZN", 2)) {
+ // On Windows, dbghelp strips leading underscores, so we accept "ZN...E"
+ // form too.
+ inner = s + 2;
+ inner_len = s_len - 2;
+ } else if (s_len >= 4 && !strncmp(s, "__ZN", 4)) {
+ // On OSX, symbols are prefixed with an extra _
+ inner = s + 4;
+ inner_len = s_len - 4;
+ } else {
+ return DemangleInvalid;
+ }
+
+ if (!str_isascii(inner, inner_len)) {
+ return DemangleInvalid;
+ }
+
+ size_t elements = 0;
+ const char *chars = inner;
+ size_t chars_len = inner_len;
+ if (chars_len == 0) {
+ return DemangleInvalid;
+ }
+ char c;
+ while ((c = *chars) != 'E') {
+ // Decode an identifier element's length
+ if (c < '0' || c > '9') {
+ return DemangleInvalid;
+ }
+ size_t len = 0;
+ while (c >= '0' && c <= '9') {
+ size_t d = c - '0';
+ if (len > SIZE_MAX / 10) {
+ return DemangleInvalid;
+ }
+ len *= 10;
+ if (len > SIZE_MAX - d) {
+ return DemangleInvalid;
+ }
+ len += d;
+
+ chars++;
+ chars_len--;
+ if (chars_len == 0) {
+ return DemangleInvalid;
+ }
+ c = *chars;
+ }
+
+ // Advance by the length
+ if (chars_len <= len) {
+ return DemangleInvalid;
+ }
+ chars += len;
+ chars_len -= len;
+ elements++;
+ }
+ *res = (struct demangle_legacy) { inner, inner_len, elements };
+ *rest = chars + 1;
+ return DemangleOk;
+}
+
+static bool is_rust_hash(const char *s, size_t len) {
+ if (len == 0 || s[0] != 'h') {
+ return false;
+ }
+
+ for (size_t i = 1; i < len; i++) {
+ if (!((s[i] >= '0' && s[i] <= '9') || (s[i] >= 'a' && s[i] <= 'f') || (s[i] >= 'A' && s[i] <= 'F'))) {
+ return false;
+ }
+ }
+
+ return true;
+}
+
+NODISCARD static overflow_status rust_demangle_legacy_display_demangle(struct demangle_legacy res, char *out, size_t len, bool alternate)
+{
+ struct printer printer = {
+ // not actually using the parser part of the printer, just keeping it to share the format functions
+ DemangleOk,
+ { NULL },
+ out,
+ len,
+ 0,
+ alternate
+ };
+ const char *inner = res.mangled;
+ for (size_t element = 0; element < res.elements; element++) {
+ size_t i = 0;
+ const char *rest;
+ for (rest = inner; rest < res.mangled + res.mangled_len && *rest >= '0' && *rest <= '9'; rest++) {
+ i *= 10;
+ i += *rest - '0';
+ }
+ if ((size_t)(res.mangled + res.mangled_len - rest) < i) {
+ // safety: shouldn't reach this place if the input string is validated. bail out.
+ // safety: we knwo rest <= res.mangled + res.mangled_len from the for-loop above
+ break;
+ }
+
+ size_t len = i;
+ inner = rest + len;
+
+ // From here on, inner contains a pointer to the next element, rest[:len] to the current one
+ if (alternate && element + 1 == res.elements && is_rust_hash(rest, i)) {
+ break;
+ }
+ if (element != 0) {
+ PRINT_STR(&printer, "::");
+ }
+
+ if (len >= 2 && !strncmp(rest, "_$", 2)) {
+ rest++;
+ len--;
+ }
+
+ while (len > 0) {
+ if (rest[0] == '.') {
+ if (len >= 2 && rest[1] == '.') {
+ PRINT_STR(&printer, "::");
+ rest += 2;
+ len -= 2;
+ } else {
+ PRINT_STR(&printer, ".");
+ rest += 1;
+ len -= 1;
+ }
+ } else if (rest[0] == '$') {
+ const char *escape = memchr(rest + 1, '$', len - 1);
+ if (escape == NULL) {
+ break;
+ }
+ const char *escape_start = rest + 1;
+ size_t escape_len = escape - (rest + 1);
+
+ size_t next_len = len - (escape + 1 - rest);
+ const char *next_rest = escape + 1;
+
+ char ch;
+ if ((escape_len == 2 && escape_start[0] == 'S' && escape_start[1] == 'P')) {
+ ch = '@';
+ } else if ((escape_len == 2 && escape_start[0] == 'B' && escape_start[1] == 'P')) {
+ ch = '*';
+ } else if ((escape_len == 2 && escape_start[0] == 'R' && escape_start[1] == 'F')) {
+ ch = '&';
+ } else if ((escape_len == 2 && escape_start[0] == 'L' && escape_start[1] == 'T')) {
+ ch = '<';
+ } else if ((escape_len == 2 && escape_start[0] == 'G' && escape_start[1] == 'T')) {
+ ch = '>';
+ } else if ((escape_len == 2 && escape_start[0] == 'L' && escape_start[1] == 'P')) {
+ ch = '(';
+ } else if ((escape_len == 2 && escape_start[0] == 'R' && escape_start[1] == 'P')) {
+ ch = ')';
+ } else if ((escape_len == 1 && escape_start[0] == 'C')) {
+ ch = ',';
+ } else {
+ if (escape_len > 1 && escape_start[0] == 'u') {
+ escape_start++;
+ escape_len--;
+ uint64_t val;
+ if (try_parse_uint(escape_start, escape_len, &val)
+ && val < UINT32_MAX
+ && validate_char((uint32_t)val))
+ {
+ if (!unicode_iscontrol(val)) {
+ uint8_t wchr[4];
+ size_t wchr_len = code_to_utf8(wchr, (uint32_t)val);
+ PRINT(printer_print_buf(&printer, (const char*)wchr, wchr_len));
+ len = next_len;
+ rest = next_rest;
+ continue;
+ }
+ }
+ }
+ break; // print the rest of this element raw
+ }
+ PRINT_CH(&printer, ch);
+ len = next_len;
+ rest = next_rest;
+ } else {
+ size_t j = 0;
+ for (;j < len && rest[j] != '$' && rest[j] != '.';j++);
+ if (j == len) {
+ break;
+ }
+ PRINT(printer_print_buf(&printer, rest, j));
+ rest += j;
+ len -= j;
+ }
+ }
+ PRINT(printer_print_buf(&printer, rest, len));
+ }
+
+ if (printer.out_len < OVERFLOW_MARGIN) {
+ return OverflowOverflow;
+ }
+ *printer.out = '\0';
+ return OverflowOk;
+}
+
+static bool is_symbol_like(const char *s, size_t len) {
+ // rust-demangle definition of symbol like: control characters and space are not symbol-like, all else is
+ for (size_t i = 0; i < len; i++) {
+ char ch = s[i];
+ if (!(ch >= 0x21 && ch <= 0x7e)) {
+ return false;
+ }
+ }
+ return true;
+}
+
+void rust_demangle_demangle(const char *s, struct demangle *res)
+{
+ // During ThinLTO LLVM may import and rename internal symbols, so strip out
+ // those endings first as they're one of the last manglings applied to symbol
+ // names.
+ const char *llvm = ".llvm.";
+ const char *found_llvm = strstr(s, llvm);
+ size_t s_len = strlen(s);
+ if (found_llvm) {
+ const char *all_hex_ptr = found_llvm + strlen(".llvm.");
+ bool all_hex = true;
+ for (;*all_hex_ptr;all_hex_ptr++) {
+ if (!(('0' <= *all_hex_ptr && *all_hex_ptr <= '9') ||
+ ('A' <= *all_hex_ptr && *all_hex_ptr <= 'F') ||
+ *all_hex_ptr == '@')) {
+ all_hex = false;
+ break;
+ }
+ }
+
+ if (all_hex) {
+ s_len = found_llvm - s;
+ }
+ }
+
+ const char *suffix;
+ struct demangle_legacy legacy;
+ demangle_status st = rust_demangle_legacy_demangle(s, s_len, &legacy, &suffix);
+ if (st == DemangleOk) {
+ *res = (struct demangle) {
+ .style=DemangleStyleLegacy,
+ .mangled=legacy.mangled,
+ .mangled_len=legacy.mangled_len,
+ .elements=legacy.elements,
+ .original=s,
+ .original_len=s_len,
+ .suffix=suffix,
+ .suffix_len=s_len - (suffix - s),
+ };
+ } else {
+ struct demangle_v0 v0;
+ st = rust_demangle_v0_demangle(s, s_len, &v0, &suffix);
+ if (st == DemangleOk) {
+ *res = (struct demangle) {
+ .style=DemangleStyleV0,
+ .mangled=v0.mangled,
+ .mangled_len=v0.mangled_len,
+ .elements=0,
+ .original=s,
+ .original_len=s_len,
+ .suffix=suffix,
+ .suffix_len=s_len - (suffix - s),
+ };
+ } else {
+ *res = (struct demangle) {
+ .style=DemangleStyleUnknown,
+ .mangled=NULL,
+ .mangled_len=0,
+ .elements=0,
+ .original=s,
+ .original_len=s_len,
+ .suffix=s,
+ .suffix_len=0,
+ };
+ }
+ }
+
+ // Output like LLVM IR adds extra period-delimited words. See if
+ // we are in that case and save the trailing words if so.
+ if (res->suffix_len) {
+ if (res->suffix[0] == '.' && is_symbol_like(res->suffix, res->suffix_len)) {
+ // Keep the suffix
+ } else {
+ // Reset the suffix and invalidate the demangling
+ res->style = DemangleStyleUnknown;
+ res->suffix_len = 0;
+ }
+ }
+}
+
+bool rust_demangle_is_known(struct demangle *res) {
+ return res->style != DemangleStyleUnknown;
+}
+
+overflow_status rust_demangle_display_demangle(struct demangle const *res, char *out, size_t len, bool alternate) {
+ size_t original_len = res->original_len;
+ size_t out_len;
+ switch (res->style) {
+ case DemangleStyleUnknown:
+ if (len < original_len) {
+ return OverflowOverflow;
+ } else {
+ memcpy(out, res->original, original_len);
+ out += original_len;
+ len -= original_len;
+ break;
+ }
+ break;
+ case DemangleStyleLegacy: {
+ struct demangle_legacy legacy = {
+ res->mangled,
+ res->mangled_len,
+ res->elements
+ };
+ if (rust_demangle_legacy_display_demangle(legacy, out, len, alternate) == OverflowOverflow) {
+ return OverflowOverflow;
+ }
+ out_len = strlen(out);
+ out += out_len;
+ len -= out_len;
+ break;
+ }
+ case DemangleStyleV0: {
+ struct demangle_v0 v0 = {
+ res->mangled,
+ res->mangled_len
+ };
+ if (rust_demangle_v0_display_demangle(v0, out, len, alternate) == OverflowOverflow) {
+ return OverflowOverflow;
+ }
+ out_len = strlen(out);
+ out += out_len;
+ len -= out_len;
+ break;
+ }
+ }
+ size_t suffix_len = res->suffix_len;
+ if (len < suffix_len || len - suffix_len < OVERFLOW_MARGIN) {
+ return OverflowOverflow;
+ }
+ memcpy(out, res->suffix, suffix_len);
+ out[suffix_len] = 0;
+ return OverflowOk;
+}
diff --git a/tools/perf/util/demangle-rust-v0.h b/tools/perf/util/demangle-rust-v0.h
new file mode 100644
index 000000000000..d0092818610a
--- /dev/null
+++ b/tools/perf/util/demangle-rust-v0.h
@@ -0,0 +1,88 @@
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+
+// The contents of this file come from the Rust rustc-demangle library, hosted
+// in the <https://github.com/rust-lang/rustc-demangle> repository, licensed
+// under "Apache-2.0 OR MIT". For copyright details, see
+// <https://github.com/rust-lang/rustc-demangle/blob/main/README.md>.
+// Please note that the file should be kept as close as possible to upstream.
+
+#ifndef _H_DEMANGLE_V0_H
+#define _H_DEMANGLE_V0_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <stddef.h>
+
+#if defined(__GNUC__) || defined(__clang__)
+#define DEMANGLE_NODISCARD __attribute__((warn_unused_result))
+#else
+#define DEMANGLE_NODISCARD
+#endif
+
+typedef enum {
+ OverflowOk,
+ OverflowOverflow
+} overflow_status;
+
+enum demangle_style {
+ DemangleStyleUnknown = 0,
+ DemangleStyleLegacy,
+ DemangleStyleV0,
+};
+
+// Not using a union here to make the struct easier to copy-paste if needed.
+struct demangle {
+ enum demangle_style style;
+ // points to the "mangled" part of the name,
+ // not including `ZN` or `R` prefixes.
+ const char *mangled;
+ size_t mangled_len;
+ // In DemangleStyleLegacy, is the number of path elements
+ size_t elements;
+ // while it's called "original", it will not contain `.llvm.9D1C9369@@16` suffixes
+ // that are to be ignored.
+ const char *original;
+ size_t original_len;
+ // Contains the part after the mangled name that is to be outputted,
+ // which can be `.exit.i.i` suffixes LLVM sometimes adds.
+ const char *suffix;
+ size_t suffix_len;
+};
+
+// if the length of the output buffer is less than `output_len-OVERFLOW_MARGIN`,
+// the demangler will return `OverflowOverflow` even if there is no overflow.
+#define OVERFLOW_MARGIN 4
+
+/// Demangle a C string that refers to a Rust symbol and put the demangle intermediate result in `res`.
+/// Beware that `res` contains references into `s`. If `s` is modified (or free'd) before calling
+/// `rust_demangle_display_demangle` behavior is undefined.
+///
+/// Use `rust_demangle_display_demangle` to convert it to an actual string.
+void rust_demangle_demangle(const char *s, struct demangle *res);
+
+/// Write the string in a `struct demangle` into a buffer.
+///
+/// Return `OverflowOk` if the output buffer was sufficiently big, `OverflowOverflow` if it wasn't.
+/// This function is `O(n)` in the length of the input + *output* [$], but the demangled output of demangling a symbol can
+/// be exponentially[$$] large, therefore it is recommended to have a sane bound (`rust-demangle`
+/// uses 1,000,000 bytes) on `len`.
+///
+/// `alternate`, if true, uses the less verbose alternate formatting (Rust `{:#}`) is used, which does not show
+/// symbol hashes and types of constant ints.
+///
+/// [$] It's `O(n * MAX_DEPTH)`, but `MAX_DEPTH` is a constant 300 and therefore it's `O(n)`
+/// [$$] Technically, bounded by `O(n^MAX_DEPTH)`, but this is practically exponential.
+DEMANGLE_NODISCARD overflow_status rust_demangle_display_demangle(struct demangle const *res, char *out, size_t len, bool alternate);
+
+/// Returns true if `res` refers to a known valid Rust demangling style, false if it's an unknown style.
+bool rust_demangle_is_known(struct demangle *res);
+
+#undef DEMANGLE_NODISCARD
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
--
2.49.0.901.g37484f566f-goog
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