From: Andi Kleen <a...@linux.intel.com>
When running creduce on an ICE substantial amounts of the total
CPU time go to backtrace_qsort() (sorting dwarf of the compiler) for
printing the backtrace of the ICE. When running a reduction we don't need the
backtrace. So add a -dB option to turn it off, and make reduction
a bit faster.
Passes bootstrap and testing on x86_64-linux
gcc/:
2017-05-16 Andi Kleen <a...@linux.intel.com>
* diagnostic.c (diagnostic_initialize): Set disable_backtrace to
false.
(diagnostic_action_after_output): Check disable_backtrace.
* diagnostic.h (struct diagnostic_context): Add
disable_backtrace.
* doc/invoke.texi (-dB): Document.
* opts.c (decode_d_option): Handle -dB.
---
gcc/diagnostic.c | 16 ++++++++++------
gcc/diagnostic.h | 7 +++++++
gcc/doc/invoke.texi | 6 ++++++
gcc/opts.c | 3 +++
4 files changed, 26 insertions(+), 6 deletions(-)
diff --git a/gcc/diagnostic.c b/gcc/diagnostic.c
index 158519606f8..bbac3f384d4 100644
--- a/gcc/diagnostic.c
+++ b/gcc/diagnostic.c
@@ -156,6 +156,7 @@ diagnostic_initialize (diagnostic_context *context, int
n_opts)
context->caret_chars[i] = '^';
context->show_option_requested = false;
context->abort_on_error = false;
+ context->disable_backtrace = false;
context->show_column = false;
context->pedantic_errors = false;
context->permissive = false;
@@ -500,13 +501,16 @@ diagnostic_action_after_output (diagnostic_context
*context,
case DK_ICE:
case DK_ICE_NOBT:
{
- struct backtrace_state *state = NULL;
- if (diag_kind == DK_ICE)
- state = backtrace_create_state (NULL, 0, bt_err_callback, NULL);
int count = 0;
- if (state != NULL)
- backtrace_full (state, 2, bt_callback, bt_err_callback,
- (void *) &count);
+ if (!context->disable_backtrace)
+ {
+ struct backtrace_state *state = NULL;
+ if (diag_kind == DK_ICE)
+ state = backtrace_create_state (NULL, 0, bt_err_callback, NULL);
+ if (state != NULL)
+ backtrace_full (state, 2, bt_callback, bt_err_callback,
+ (void *) &count);
+ }
if (context->abort_on_error)
real_abort ();
diff --git a/gcc/diagnostic.h b/gcc/diagnostic.h
index dbd1703e0ef..440b547c6da 100644
--- a/gcc/diagnostic.h
+++ b/gcc/diagnostic.h
@@ -120,6 +120,9 @@ struct diagnostic_context
/* True if we should raise a SIGABRT on errors. */
bool abort_on_error;
+ /* If true don't print backtraces for internal errors. */
+ bool disable_backtrace;
+
/* True if we should show the column number on diagnostics. */
bool show_column;
@@ -245,6 +248,10 @@ diagnostic_inhibit_notes (diagnostic_context * context)
#define diagnostic_abort_on_error(DC) \
(DC)->abort_on_error = true
+/* Don't print backtraces for internal errors. */
+#define diagnostic_disable_backtrace(DC) \
+ (DC)->disable_backtrace = true;
+
/* This diagnostic_context is used by front-ends that directly output
diagnostic messages without going through `error', `warning',
and similar functions. */
diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi
index 715830a1a43..677e78c7078 100644
--- a/gcc/doc/invoke.texi
+++ b/gcc/doc/invoke.texi
@@ -12889,6 +12889,12 @@ Produce all the dumps listed above.
@opindex dA
Annotate the assembler output with miscellaneous debugging information.
+@item -dB
+@opindex dB
+Do not print backtraces on compiler crashes. This speeds up reducing
+test cases for compiler crashes, because printing backtraces is relatively
+slow.
+
@item -dD
@opindex dD
Dump all macro definitions, at the end of preprocessing, in addition to
diff --git a/gcc/opts.c b/gcc/opts.c
index ffedb10f18f..0c1da107714 100644
--- a/gcc/opts.c
+++ b/gcc/opts.c
@@ -2593,6 +2593,9 @@ decode_d_option (const char *arg, struct gcc_options
*opts,
case 'a':
opts->x_flag_dump_all_passed = true;
break;
+ case 'B':
+ diagnostic_disable_backtrace (dc);
+ break;
default:
warning_at (loc, 0, "unrecognized gcc debugging option: %c", c);
--
2.12.2
