I’m running historical performance experiments, and this commit from 2019 showed up on my radar. Just in case someone is interested in running Fortran code on memory-constrained M-profile cores ...

It appears that Janne’s patch increases code-size of 437.leslie3d by around 2% on 32-bit ARM (well, Thumb2, to be precise). It may be interesting to check what’s going on, since AArch64 is not affected.

One possibility is that before this patch all literal-pool entries for error messages were shared, and with variation of error messages all of them became different entries, thus increasing code size.

-- Maxim Kuvyrkov https://www.linaro.org

On 28 Jun 2021, at 00:54, ci_notify@linaro.org wrote:

Successfully identified regression in *gcc* in CI configuration tcwg_bmk_gnu_tk1/gnu-release-arm-spec2k6-Os_LTO. So far, this commit has regressed CI configurations:

• tcwg_bmk_gnu_tk1/gnu-release-arm-spec2k6-Os_LTO
• tcwg_bmk_tk1/gnu-release-arm-spec2k6-Os

Culprit:

<cut> commit d74a8b0579edd0c42921eccc45ab986d24f2fef0 Author: Janne Blomqvist <jb@gcc.gnu.org>

PR fortran/68401 Improve allocation error message

</cut>

Results regressed to (for first_bad == d74a8b0579edd0c42921eccc45ab986d24f2fef0) # reset_artifacts: -10 # build_abe binutils: -9 # build_abe stage1 -- --set gcc_override_configure=--with-mode=thumb --set gcc_override_configure=--disable-libsanitizer: -8 # build_abe linux: -7 # build_abe glibc: -6 # build_abe stage2 -- --set gcc_override_configure=--with-mode=thumb --set gcc_override_configure=--disable-libsanitizer: -5 # true: 0 # benchmark -Os_LTO_mthumb -- artifacts/build-d74a8b0579edd0c42921eccc45ab986d24f2fef0/results_id: 1 # 437.leslie3d,leslie3d_base.default regressed by 102

from (for last_good == 777c02825229f14cf91c6044827ea42a77ded4a3) # reset_artifacts: -10 # build_abe binutils: -9 # build_abe stage1 -- --set gcc_override_configure=--with-mode=thumb --set gcc_override_configure=--disable-libsanitizer: -8 # build_abe linux: -7 # build_abe glibc: -6 # build_abe stage2 -- --set gcc_override_configure=--with-mode=thumb --set gcc_override_configure=--disable-libsanitizer: -5 # true: 0 # benchmark -Os_LTO_mthumb -- artifacts/build-777c02825229f14cf91c6044827ea42a77ded4a3/results_id: 1

Artifacts of last_good build: https://ci.linaro.org/job/tcwg_bmk_ci_gnu-bisect-tcwg_bmk_tk1-gnu-release-ar... Results ID of last_good: tk1_32/tcwg_bmk_gnu_tk1/bisect-gnu-release-arm-spec2k6-Os_LTO/531 Artifacts of first_bad build: https://ci.linaro.org/job/tcwg_bmk_ci_gnu-bisect-tcwg_bmk_tk1-gnu-release-ar... Results ID of first_bad: tk1_32/tcwg_bmk_gnu_tk1/bisect-gnu-release-arm-spec2k6-Os_LTO/539 Build top page/logs: https://ci.linaro.org/job/tcwg_bmk_ci_gnu-bisect-tcwg_bmk_tk1-gnu-release-ar...

Configuration details:

Reproduce builds:

<cut> mkdir investigate-gcc-d74a8b0579edd0c42921eccc45ab986d24f2fef0 cd investigate-gcc-d74a8b0579edd0c42921eccc45ab986d24f2fef0

git clone https://git.linaro.org/toolchain/jenkins-scripts

mkdir -p artifacts/manifests curl -o artifacts/manifests/build-baseline.sh https://ci.linaro.org/job/tcwg_bmk_ci_gnu-bisect-tcwg_bmk_tk1-gnu-release-ar... --fail curl -o artifacts/manifests/build-parameters.sh https://ci.linaro.org/job/tcwg_bmk_ci_gnu-bisect-tcwg_bmk_tk1-gnu-release-ar... --fail curl -o artifacts/test.sh https://ci.linaro.org/job/tcwg_bmk_ci_gnu-bisect-tcwg_bmk_tk1-gnu-release-ar... --fail chmod +x artifacts/test.sh

# Reproduce the baseline build (build all pre-requisites) ./jenkins-scripts/tcwg_bmk-build.sh @@ artifacts/manifests/build-baseline.sh

cd gcc

# Reproduce first_bad build git checkout --detach d74a8b0579edd0c42921eccc45ab986d24f2fef0 ../artifacts/test.sh

# Reproduce last_good build git checkout --detach 777c02825229f14cf91c6044827ea42a77ded4a3 ../artifacts/test.sh

cd ..

</cut>

History of pending regressions and results: https://git.linaro.org/toolchain/ci/base-artifacts.git/log/?h=linaro-local/c...

Artifacts: https://ci.linaro.org/job/tcwg_bmk_ci_gnu-bisect-tcwg_bmk_tk1-gnu-release-ar... Build log: https://ci.linaro.org/job/tcwg_bmk_ci_gnu-bisect-tcwg_bmk_tk1-gnu-release-ar...

Full commit (up to 1000 lines):

<cut> commit d74a8b0579edd0c42921eccc45ab986d24f2fef0 Author: Janne Blomqvist <jb@gcc.gnu.org> Date: Sat Aug 17 08:45:37 2019 +0300

PR fortran/68401 Improve allocation error message

Improve the error message that is printed when a memory allocation fails, by including the location, and the size of the allocation that failed.

Regtested on x86_64-pc-linux-gnu.

gcc/fortran/ChangeLog:

2019-08-17 Janne Blomqvist jb@gcc.gnu.org

       PR fortran/68401
       * trans-decl.c (gfc_build_builtin_function_decls): Replace
       os_error with os_error_at decl.
       * trans.c (trans_runtime_error_vararg): Modify so the error
       function decl is passed directly.
       (gfc_trans_runtime_error): Pass correct error function decl.
       (gfc_trans_runtime_check): Likewise.
       (trans_os_error_at): New function.
       (gfc_call_malloc): Use trans_os_error_at.
       (gfc_allocate_using_malloc): Likewise.
       (gfc_call_realloc): Likewise.
       * trans.h (gfor_fndecl_os_error): Replace with gfor_fndecl_os_error_at.

libgfortran/ChangeLog:

2019-08-17 Janne Blomqvist jb@gcc.gnu.org

       PR fortran/68401
       * gfortran.map: Add GFORTRAN_10 node, add _gfortran_os_error_at
       symbol.
       * libgfortran.h (os_error_at): New prototype.
       * runtime/error.c (os_error_at): New function.

From-SVN: r274599

gcc/fortran/ChangeLog | 17 +++++++++++- gcc/fortran/trans-decl.c | 12 ++++---- gcc/fortran/trans.c | 68 +++++++++++++++++++++++++++------------------ gcc/fortran/trans.h | 2 +- libgfortran/ChangeLog | 8 ++++++ libgfortran/gfortran.map | 5 ++++ libgfortran/libgfortran.h | 4 +++ libgfortran/runtime/error.c | 46 +++++++++++++++++++++++++++++- 8 files changed, 126 insertions(+), 36 deletions(-)

diff --git a/gcc/fortran/ChangeLog b/gcc/fortran/ChangeLog index bab69f3000e..a3b9e6bf486 100644 --- a/gcc/fortran/ChangeLog +++ b/gcc/fortran/ChangeLog @@ -1,3 +1,18 @@ +2019-08-17 Janne Blomqvist jb@gcc.gnu.org

• PR fortran/68401
• • trans-decl.c (gfc_build_builtin_function_decls): Replace
• os_error with os_error_at decl.
• • trans.c (trans_runtime_error_vararg): Modify so the error
• function decl is passed directly.
• (gfc_trans_runtime_error): Pass correct error function decl.
• (gfc_trans_runtime_check): Likewise.
• (trans_os_error_at): New function.
• (gfc_call_malloc): Use trans_os_error_at.
• (gfc_allocate_using_malloc): Likewise.
• (gfc_call_realloc): Likewise.
• • trans.h (gfor_fndecl_os_error): Replace with gfor_fndecl_os_error_at.

2019-08-16 Jeff Law law@redhat.com Mark Eggleston mark.eggleston@codethink.com

@@ -18,7 +33,7 @@

• trans-common.c (find_equivalence) : New local variable dummy_symbol,

accumulated equivalence attributes from each symbol then check for conflicts.

2019-08-16 Richard Biener rguenther@suse.de

• trans-intrinsic.c (gfc_conv_intrinsic_findloc): Initialize

diff --git a/gcc/fortran/trans-decl.c b/gcc/fortran/trans-decl.c index 2a9b852568a..3c6ab60e9b2 100644 --- a/gcc/fortran/trans-decl.c +++ b/gcc/fortran/trans-decl.c @@ -102,7 +102,7 @@ tree gfor_fndecl_error_stop_string; tree gfor_fndecl_runtime_error; tree gfor_fndecl_runtime_error_at; tree gfor_fndecl_runtime_warning_at; -tree gfor_fndecl_os_error; +tree gfor_fndecl_os_error_at; tree gfor_fndecl_generate_error; tree gfor_fndecl_set_args; tree gfor_fndecl_set_fpe; @@ -3679,11 +3679,11 @@ gfc_build_builtin_function_decls (void) void_type_node, 3, pvoid_type_node, integer_type_node, pchar_type_node);

• gfor_fndecl_os_error = gfc_build_library_function_decl_with_spec (
• get_identifier (PREFIX("os_error")), ".R",
• void_type_node, 1, pchar_type_node);
• /* The runtime_error function does not return. */
• TREE_THIS_VOLATILE (gfor_fndecl_os_error) = 1;

• gfor_fndecl_os_error_at = gfc_build_library_function_decl_with_spec (

• get_identifier (PREFIX("os_error_at")), ".RR",

• void_type_node, -2, pchar_type_node, pchar_type_node);

• /* The os_error_at function does not return. */

• TREE_THIS_VOLATILE (gfor_fndecl_os_error_at) = 1;

  gfor_fndecl_set_args = gfc_build_library_function_decl ( get_identifier (PREFIX("set_args")),

diff --git a/gcc/fortran/trans.c b/gcc/fortran/trans.c index 84511477b39..583f6e3b25b 100644 --- a/gcc/fortran/trans.c +++ b/gcc/fortran/trans.c @@ -447,7 +447,7 @@ gfc_build_array_ref (tree base, tree offset, tree decl, tree vptr) arguments and a locus. */

static tree -trans_runtime_error_vararg (bool error, locus* where, const char* msgid, +trans_runtime_error_vararg (tree errorfunc, locus* where, const char* msgid, va_list ap) { stmtblock_t block; @@ -501,18 +501,13 @@ trans_runtime_error_vararg (bool error, locus* where, const char* msgid, /* Build the function call to runtime_(warning,error)_at; because of the variable number of arguments, we can't use build_call_expr_loc dinput_location, irectly. */

• if (error)
• fntype = TREE_TYPE (gfor_fndecl_runtime_error_at);
• else
• fntype = TREE_TYPE (gfor_fndecl_runtime_warning_at);

• fntype = TREE_TYPE (errorfunc);

  loc = where ? where->lb->location : input_location; tmp = fold_build_call_array_loc (loc, TREE_TYPE (fntype), fold_build1_loc (loc, ADDR_EXPR, build_pointer_type (fntype),

• 			     error
  

• 			     ? gfor_fndecl_runtime_error_at
  

• 			     : gfor_fndecl_runtime_warning_at),
  

• 			     errorfunc),
  	   nargs + 2, argarray);
  

  gfc_add_expr_to_block (&block, tmp);

@@ -527,7 +522,10 @@ gfc_trans_runtime_error (bool error, locus* where, const char* msgid, ...) tree result;

va_start (ap, msgid);

• result = trans_runtime_error_vararg (error, where, msgid, ap);

• result = trans_runtime_error_vararg (error

• 		       ? gfor_fndecl_runtime_error_at
  

• 		       : gfor_fndecl_runtime_warning_at,
  

• 		       where, msgid, ap);
  

  va_end (ap); return result;

} @@ -566,8 +564,10 @@ gfc_trans_runtime_check (bool error, bool once, tree cond, stmtblock_t * pblock, /* The code to generate the error. */ va_start (ap, msgid); gfc_add_expr_to_block (&block,

• 	 trans_runtime_error_vararg (error, where,
  

• 				     msgid, ap));
  

• 	 trans_runtime_error_vararg
  

• 	 (error ? gfor_fndecl_runtime_error_at
  

• 	  : gfor_fndecl_runtime_warning_at,
  

• 	  where, msgid, ap));
  

  va_end (ap);

  if (once)

@@ -595,13 +595,28 @@ gfc_trans_runtime_check (bool error, bool once, tree cond, stmtblock_t * pblock, }

+static tree +trans_os_error_at (locus* where, const char* msgid, ...) +{

• va_list ap;
• tree result;
• va_start (ap, msgid);
• result = trans_runtime_error_vararg (gfor_fndecl_os_error_at,

• 		       where, msgid, ap);
  

• va_end (ap);
• return result;

+}

/* Call malloc to allocate size bytes of memory, with special conditions: + if size == 0, return a malloced area of size 1, + if malloc returns NULL, issue a runtime error. */ tree gfc_call_malloc (stmtblock_t * block, tree type, tree size) {

• tree tmp, msg, malloc_result, null_result, res, malloc_tree;

• tree tmp, malloc_result, null_result, res, malloc_tree; stmtblock_t block2;

  /* Create a variable to hold the result. */

@@ -626,13 +641,14 @@ gfc_call_malloc (stmtblock_t * block, tree type, tree size) null_result = fold_build2_loc (input_location, EQ_EXPR, logical_type_node, res, build_int_cst (pvoid_type_node, 0));

•  msg = gfc_build_addr_expr (pchar_type_node,
  

•      gfc_build_localized_cstring_const ("Memory allocation failed"));
  tmp = fold_build3_loc (input_location, COND_EXPR, void_type_node,
       null_result,
  

•      build_call_expr_loc (input_location,
  

• 		   gfor_fndecl_os_error, 1, msg),
  

• 		   build_empty_stmt (input_location));
  

• 	     trans_os_error_at (NULL,
  

• 				"Error allocating %lu bytes",
  

• 				fold_convert
  

• 				(long_unsigned_type_node,
  

• 				 size)),
  

• 	     build_empty_stmt (input_location));
  

  gfc_add_expr_to_block (&block2, tmp); }

@@ -701,11 +717,9 @@ gfc_allocate_using_malloc (stmtblock_t * block, tree pointer, } else {

•  /* Here, os_error already implies PRED_NORETURN.  */
  

•  tmp = build_call_expr_loc (input_location, gfor_fndecl_os_error, 1,
  

•     gfc_build_addr_expr (pchar_type_node,
  

• 		 gfc_build_localized_cstring_const
  

• 		    ("Allocation would exceed memory limit")));
  

•  /* Here, os_error_at already implies PRED_NORETURN.  */
  

•  tree lusize = fold_convert (long_unsigned_type_node, size);
  

•  tmp = trans_os_error_at (NULL, "Error allocating %lu bytes", lusize);
  gfc_add_expr_to_block (&on_error, tmp);
  

  }

@@ -1664,7 +1678,7 @@ internal_realloc (void *mem, size_t size) tree gfc_call_realloc (stmtblock_t * block, tree mem, tree size) {

• tree msg, res, nonzero, null_result, tmp;

• tree res, nonzero, null_result, tmp; tree type = TREE_TYPE (mem);

  /* Only evaluate the size once. */

@@ -1684,12 +1698,12 @@ gfc_call_realloc (stmtblock_t * block, tree mem, tree size) build_int_cst (size_type_node, 0)); null_result = fold_build2_loc (input_location, TRUTH_AND_EXPR, logical_type_node, null_result, nonzero);

• msg = gfc_build_addr_expr (pchar_type_node, gfc_build_localized_cstring_const

• 	     ("Allocation would exceed memory limit"));
  

  tmp = fold_build3_loc (input_location, COND_EXPR, void_type_node, null_result,

• 	 build_call_expr_loc (input_location,
  

• 			      gfor_fndecl_os_error, 1, msg),
  

• 	 trans_os_error_at (NULL,
  

• 			    "Error reallocating to %lu bytes",
  

• 			    fold_convert
  

• 			    (long_unsigned_type_node, size)),
   build_empty_stmt (input_location));
  

  gfc_add_expr_to_block (block, tmp);

diff --git a/gcc/fortran/trans.h b/gcc/fortran/trans.h index a3726e84140..8082b414df1 100644 --- a/gcc/fortran/trans.h +++ b/gcc/fortran/trans.h @@ -803,7 +803,7 @@ extern GTY(()) tree gfor_fndecl_error_stop_string; extern GTY(()) tree gfor_fndecl_runtime_error; extern GTY(()) tree gfor_fndecl_runtime_error_at; extern GTY(()) tree gfor_fndecl_runtime_warning_at; -extern GTY(()) tree gfor_fndecl_os_error; +extern GTY(()) tree gfor_fndecl_os_error_at; extern GTY(()) tree gfor_fndecl_generate_error; extern GTY(()) tree gfor_fndecl_set_fpe; extern GTY(()) tree gfor_fndecl_set_options; diff --git a/libgfortran/ChangeLog b/libgfortran/ChangeLog index 7a11ca29fd3..23a4c579351 100644 --- a/libgfortran/ChangeLog +++ b/libgfortran/ChangeLog @@ -1,3 +1,11 @@ +2019-08-17 Janne Blomqvist jb@gcc.gnu.org

• PR fortran/68401
• • gfortran.map: Add GFORTRAN_10 node, add _gfortran_os_error_at
• symbol.
• • libgfortran.h (os_error_at): New prototype.
• • runtime/error.c (os_error_at): New function.

2019-08-13 Janne Blomqvist jb@gcc.gnu.org

    PR fortran/91414

diff --git a/libgfortran/gfortran.map b/libgfortran/gfortran.map index 2b2243b4fd4..3601bc24414 100644 --- a/libgfortran/gfortran.map +++ b/libgfortran/gfortran.map @@ -1602,3 +1602,8 @@ GFORTRAN_9.2 { _gfortran_mfindloc1_r10; _gfortran_sfindloc1_r10; } GFORTRAN_9;

+GFORTRAN_10 {

• global:
• _gfortran_os_error_at;

+} GFORTRAN_9.2; diff --git a/libgfortran/libgfortran.h b/libgfortran/libgfortran.h index c0db96f02a8..9f535b12e73 100644 --- a/libgfortran/libgfortran.h +++ b/libgfortran/libgfortran.h @@ -728,6 +728,10 @@ internal_proto(gfc_xtoa); extern _Noreturn void os_error (const char *); iexport_proto(os_error);

+extern _Noreturn void os_error_at (const char *, const char *, ...)

• __attribute__ ((format (gfc_printf, 2, 3)));

+iexport_proto(os_error_at);

extern void show_locus (st_parameter_common *); internal_proto(show_locus);

diff --git a/libgfortran/runtime/error.c b/libgfortran/runtime/error.c index 0335a165edc..cbe0642f3f8 100644 --- a/libgfortran/runtime/error.c +++ b/libgfortran/runtime/error.c @@ -403,7 +403,51 @@ os_error (const char *message) estr_writev (iov, 5); exit_error (1); } -iexport(os_error); +iexport(os_error); /* TODO, DEPRECATED, ABI: Should not be exported

•       anymore when bumping so version.  */
  

+/* Improved version of os_error with a printf style format string and

• a locus. */

+void +os_error_at (const char *where, const char *message, ...) +{

• char errmsg[STRERR_MAXSZ];
• char buffer[STRERR_MAXSZ];
• struct iovec iov[6];
• va_list ap;
• recursion_check ();
• int written;
• iov[0].iov_base = (char*) where;
• iov[0].iov_len = strlen (where);
• iov[1].iov_base = (char*) ": ";
• iov[1].iov_len = strlen (iov[1].iov_base);
• va_start (ap, message);
• written = vsnprintf (buffer, STRERR_MAXSZ, message, ap);
• va_end (ap);
• iov[2].iov_base = buffer;
• if (written >= 0)
• iov[2].iov_len = written;
• else
• iov[2].iov_len = 0;
• iov[3].iov_base = (char*) ": ";
• iov[3].iov_len = strlen (iov[3].iov_base);
• iov[4].iov_base = gf_strerror (errno, errmsg, STRERR_MAXSZ);
• iov[4].iov_len = strlen (iov[4].iov_base);
• iov[5].iov_base = (char*) "\n";
• iov[5].iov_len = 1;
• estr_writev (iov, 6);
• exit_error (1);

+} +iexport(os_error_at);

/* void runtime_error()-- These are errors associated with an

</cut>