procyberian/gcc
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

[-fcompare-debug] var tracking options are not optimization options

Browse source 
If we include them in the ICF hash, they may cause congruence_groups to
be processed in a different order due to different hashes, which in turn
causes different funcdef_nos to be assigned to functions.  Since these
numbers are included in -fcompare-debug dumps, they cause failures.

Since these options are not optimization options, in that they do not
(or should not, save for bugs like this) affect the executable code
output by the compiler, they should not be marked as such.

This patch replaces the Optimization flag in the var-tracking options
with the newly-introduced PerFunction flag, so that it can still be
controlled on a per-function basis, but that disregards it in the hash
computation used by ICF.

This fixes -fcompare-debug failures in numerous LTO testcases.

for  gcc/ChangeLog

	* doc/options.texi (PerFunction): New.
	* opt-functions.awk (switch_flags): Map both Optimization and
	PerFunction to CL_OPTIMIZATION.
	* opth-gen.awk: Test for PerFunction flag along with
	Optimization.
	* optc-save-gen.awk: Likewise.  Introduce var_opt_hash and set
	it only when the latter is present.  Skip those that don't in
	the hash function generator.
	* common.opt (fvar-tracking): Mark as PerFunction instead of
	Optimization.
	(fvar-tracking-assignments): Likewise.
	(fvar-tracking-assignments-toggle): Likewise.
	(fvar-tracking-uninit): Likewise.

From-SVN: r244198
This commit is contained in:
Alexandre Oliva 2017-01-07 19:53:13 +00:00 • committed by Alexandre Oliva
parent 42002dfec3
commit ff98fa955b
6 changed files with 34 additions and 8 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

16
gcc/ChangeLog
View file

@ -1,3 +1,19 @@
2017-01-07 Alexandre Oliva <aoliva@redhat.com>
* doc/options.texi (PerFunction): New.
* opt-functions.awk (switch_flags): Map both Optimization and
PerFunction to CL_OPTIMIZATION.
* opth-gen.awk: Test for PerFunction flag along with
Optimization.
* optc-save-gen.awk: Likewise. Introduce var_opt_hash and set
it only when the latter is present. Skip those that don't in
the hash function generator.
* common.opt (fvar-tracking): Mark as PerFunction instead of
Optimization.
(fvar-tracking-assignments): Likewise.
(fvar-tracking-assignments-toggle): Likewise.
(fvar-tracking-uninit): Likewise.
2017-01-07 Jakub Jelinek <jakub@redhat.com>
PR translation/79018

8
gcc/common.opt
View file

@ -2644,7 +2644,7 @@ Common Undocumented Var(flag_use_linker_plugin)
; will be set according to optimize, debug_info_level and debug_hooks
; in process_options ().
fvar-tracking
Common Report Var(flag_var_tracking) Init(2) Optimization
Common Report Var(flag_var_tracking) Init(2) PerFunction
Perform variable tracking.
; Positive if we should track variables at assignments, negative if
@ -2652,13 +2652,13 @@ Perform variable tracking.
; annotations. When flag_var_tracking_assignments ==
; AUTODETECT_VALUE it will be set according to flag_var_tracking.
fvar-tracking-assignments
Common Report Var(flag_var_tracking_assignments) Init(2) Optimization
Common Report Var(flag_var_tracking_assignments) Init(2) PerFunction
Perform variable tracking by annotating assignments.
; Nonzero if we should toggle flag_var_tracking_assignments after
; processing options and computing its default. */
fvar-tracking-assignments-toggle
Common Report Var(flag_var_tracking_assignments_toggle) Optimization
Common Report Var(flag_var_tracking_assignments_toggle) PerFunction
Toggle -fvar-tracking-assignments.
; Positive if we should track uninitialized variables, negative if
@ -2666,7 +2666,7 @@ Toggle -fvar-tracking-assignments.
; annotations. When flag_var_tracking_uninit == AUTODETECT_VALUE it
; will be set according to flag_var_tracking.
fvar-tracking-uninit
Common Report Var(flag_var_tracking_uninit) Optimization
Common Report Var(flag_var_tracking_uninit) PerFunction
Perform variable tracking and also tag variables that are uninitialized.
ftree-vectorize

7
gcc/doc/options.texi
View file

@ -430,6 +430,13 @@ This is an optimization option. It should be shown as such in
@code{Var} should be saved and restored when the optimization level is
changed with @code{optimize} attributes.
@item PerFunction
This is an option that can be overridden on a per-function basis.
@code{Optimization} implies @code{PerFunction}, but options that do not
affect executable code generation may use this flag instead, so that the
option is not taken into account in ways that might affect executable
code generation.
@item Undocumented
The option is deliberately missing documentation and should not
be included in the @option{--help} output.

2
gcc/opt-functions.awk
View file

@ -105,7 +105,7 @@ function switch_flags (flags)
test_flag("Undocumented", flags, " | CL_UNDOCUMENTED") \
test_flag("NoDWARFRecord", flags, " | CL_NO_DWARF_RECORD") \
test_flag("Warning", flags, " | CL_WARNING") \
test_flag("Optimization", flags, " | CL_OPTIMIZATION")
test_flag("(Optimization|PerFunction)", flags, " | CL_OPTIMIZATION")
sub( "^0 \\| ", "", result )
return result
}

7
gcc/optc-save-gen.awk
View file

@ -100,7 +100,7 @@ var_opt_range["optimize_debug"] = "0, 1";
# cache.
for (i = 0; i < n_opts; i++) {
if (flag_set_p("Optimization", flags[i])) {
if (flag_set_p("(Optimization|PerFunction)", flags[i])) {
name = var_name(flags[i])
if(name == "")
continue;
@ -743,7 +743,7 @@ var_opt_val[2] = "x_optimize_debug"
var_opt_val_type[1] = "char "
var_opt_val_type[2] = "char "
for (i = 0; i < n_opts; i++) {
if (flag_set_p("Optimization", flags[i])) {
if (flag_set_p("(Optimization|PerFunction)", flags[i])) {
name = var_name(flags[i])
if(name == "")
continue;
@ -756,6 +756,7 @@ for (i = 0; i < n_opts; i++) {
otype = var_type_struct(flags[i])
var_opt_val_type[n_opt_val] = otype;
var_opt_val[n_opt_val++] = "x_" name;
var_opt_hash[n_opt_val] = flag_set_p("Optimization", flags[i]);
}
}
print "";
@ -765,6 +766,8 @@ print "cl_optimization_hash (struct cl_optimization const *ptr ATTRIBUTE_UNUSED)
print "{";
print " inchash::hash hstate;";
for (i = 0; i < n_opt_val; i++) {
if (!var_opt_hash[i])
continue;
name = var_opt_val[i]
print " hstate.add_wide_int (ptr->" name");";
}

2
gcc/opth-gen.awk
View file

@ -142,7 +142,7 @@ var_opt_char[1] = "unsigned char x_optimize_size";
var_opt_char[2] = "unsigned char x_optimize_debug";
for (i = 0; i < n_opts; i++) {
if (flag_set_p("Optimization", flags[i])) {
if (flag_set_p("(Optimization|PerFunction)", flags[i])) {
name = var_name(flags[i])
if(name == "")
continue;