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[committed] Add --devel-ignore-size
Hi,
Dwz is a dwarf compression tool with the intent to transform dwarf into
equivalent but smaller dwarf. Consequently:
- during transformation it takes decisions based on size heuristics, and
- at the end of the transformation it discards the result if it's not smaller
than the original.
Currently, when we run the gdb testsuite in conjunction with dwz using
CC_WITH_TWEAKS_FLAGS, we only test dwz-transformed dwarf if in fact dwz
does not discard the result, and we only test the result of the
transformations enabled by the size heuristics.
Add a developer-only option --devel-ignore-size, that ignores size metrics
and heuristics. With this option, we force dwz to:
- move all duplicate DIEs to partial units,
- factor out all common partial unit import sets into import-only partial
units, and
- write out the result.
Also, this may prove useful in dwz test-cases to force a transformation if we
want to test that transformation.
Committed to trunk.
Thanks,
- Tom
Add --devel-ignore-size
2019-04-06 Tom de Vries <tdevries@suse.de>
* dwz.c (partition_dups_1, create_import_tree): If ignore_size, ignore
size heuristic.
(dwz): If ignore_size, skip size test.
(dwz_options): Add --devel-ignore-size.
* Makefile (TEST_EXECS): Add min.
(min): New target.
* testsuite/dwz.tests/devel-ignore-size.sh: New test.
* testsuite/dwz.tests/min-2.c: New test source.
* testsuite/dwz.tests/min.c: New test source.
---
Makefile | 5 ++++-
dwz.c | 31 +++++++++++++++++--------------
testsuite/dwz.tests/devel-ignore-size.sh | 27 +++++++++++++++++++++++++++
testsuite/dwz.tests/min-2.c | 5 +++++
testsuite/dwz.tests/min.c | 7 +++++++
5 files changed, 60 insertions(+), 15 deletions(-)
diff --git a/Makefile b/Makefile
index 7150d4a..d07a66d 100644
--- a/Makefile
+++ b/Makefile
@@ -18,7 +18,7 @@ clean:
PWD:=$(shell pwd -P)
TEST_SRC = $(PWD)/testsuite/dwz.tests
-TEST_EXECS = hello dw2-restrict py-section-script dwz-for-test
+TEST_EXECS = hello dw2-restrict py-section-script dwz-for-test min
hello:
$(CC) $(TEST_SRC)/hello.c -o $@ -g
@@ -38,6 +38,9 @@ dwz-for-test: $(DWZ_TEST_SOURCES)
$(CC) $(DWZ_TEST_SOURCES) -O2 -g -lelf -o $@ -Wall -W \
-D_FILE_OFFSET_BITS=64 -DDWZ_VERSION='"for-test"'
+min:
+ $(CC) $(TEST_SRC)/min.c $(TEST_SRC)/min-2.c -o $@ -g
+
# On some systems we need to set and export DEJAGNU to suppress
# WARNING: Couldn't find the global config file.
DEJAGNU ?= /dev/null
diff --git a/dwz.c b/dwz.c
index f1416fa..ab565d7 100644
--- a/dwz.c
+++ b/dwz.c
@@ -137,6 +137,7 @@ static struct obstack ob2;
static struct obstack alt_ob, alt_ob2;
static int tracing;
+static int ignore_size;
typedef struct
{
@@ -5407,7 +5408,7 @@ partition_dups_1 (dw_die_ref *arr, size_t vec_size,
+ (die_cu (arr[i])->cu_version == 2
? 1 + ptr_size : 5) * cnt + 10 * namespaces;
if (!second_phase)
- force = orig_size > new_size;
+ force = ignore_size || orig_size > new_size;
if (force)
{
dw_die_ref die, *diep;
@@ -5991,8 +5992,8 @@ create_import_tree (void)
cost += pusrc[srccount]->cu->cu_version == 2
? 1 + ptr_size : 5;
srccount++;
- if ((dstcount - 1) * cost
- > 13 + dstcount * new_edge_cost)
+ if (ignore_size || ((dstcount - 1) * cost
+ > 13 + dstcount * new_edge_cost))
{
unsigned int j;
@@ -6170,7 +6171,7 @@ create_import_tree (void)
&& e4->icu->cu->cu_version == 2)
? 1 + ptr_size : 5;
}
- if (size_dec > size_inc)
+ if (!ignore_size || size_dec > size_inc)
{
struct import_cu **ipup;
for (e4 = ipu2->incoming, ep = NULL; e4; e4 = e4->next)
@@ -11120,16 +11121,17 @@ dwz (const char *file, const char *outfile, struct file_result *res,
cleanup ();
ret = 1;
}
- else if (debug_sections[DEBUG_INFO].new_size
- + debug_sections[DEBUG_ABBREV].new_size
- + debug_sections[DEBUG_STR].new_size
- + debug_sections[DEBUG_MACRO].new_size
- + debug_sections[DEBUG_TYPES].new_size
- >= debug_sections[DEBUG_INFO].size
- + debug_sections[DEBUG_ABBREV].size
- + debug_sections[DEBUG_STR].size
- + debug_sections[DEBUG_MACRO].size
- + debug_sections[DEBUG_TYPES].size)
+ else if (!ignore_size
+ && ((debug_sections[DEBUG_INFO].new_size
+ + debug_sections[DEBUG_ABBREV].new_size
+ + debug_sections[DEBUG_STR].new_size
+ + debug_sections[DEBUG_MACRO].new_size
+ + debug_sections[DEBUG_TYPES].new_size)
+ >= (debug_sections[DEBUG_INFO].size
+ + debug_sections[DEBUG_ABBREV].size
+ + debug_sections[DEBUG_STR].size
+ + debug_sections[DEBUG_MACRO].size
+ + debug_sections[DEBUG_TYPES].size)))
{
if (!quiet || outfile != NULL)
error (0, 0, "%s: DWARF compression not beneficial "
@@ -11823,6 +11825,7 @@ static struct option dwz_options[] =
{ "relative", no_argument, 0, 'r' },
{ "version", no_argument, 0, 'v' },
{ "devel-trace", no_argument, &tracing, 1 },
+ { "devel-ignore-size", no_argument, &ignore_size, 1 },
{ NULL, no_argument, 0, 0 }
};
diff --git a/testsuite/dwz.tests/devel-ignore-size.sh b/testsuite/dwz.tests/devel-ignore-size.sh
new file mode 100644
index 0000000..31cc923
--- /dev/null
+++ b/testsuite/dwz.tests/devel-ignore-size.sh
@@ -0,0 +1,27 @@
+cp ../min 1
+
+cnt=$(readelf -wi 1 \
+ | grep '(DW_TAG_partial_unit' \
+ | wc -l)
+
+[ $cnt -eq 0 ]
+
+dwz 1 2>/dev/null
+
+cnt=$(readelf -wi 1 \
+ | grep '(DW_TAG_partial_unit' \
+ | wc -l)
+
+[ $cnt -eq 0 ]
+
+cp ../min 1
+
+dwz --devel-ignore-size 1
+
+cnt=$(readelf -wi 1 \
+ | grep '(DW_TAG_partial_unit' \
+ | wc -l)
+
+[ $cnt -gt 0 ]
+
+rm -f 1
diff --git a/testsuite/dwz.tests/min-2.c b/testsuite/dwz.tests/min-2.c
new file mode 100644
index 0000000..a1b61ce
--- /dev/null
+++ b/testsuite/dwz.tests/min-2.c
@@ -0,0 +1,5 @@
+int
+foo (void)
+{
+ return 0;
+}
diff --git a/testsuite/dwz.tests/min.c b/testsuite/dwz.tests/min.c
new file mode 100644
index 0000000..cd4ef42
--- /dev/null
+++ b/testsuite/dwz.tests/min.c
@@ -0,0 +1,7 @@
+extern int foo (void);
+
+int
+main (void)
+{
+ return 0;
+}