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[binutils-gdb] GAS: Consistently fix labels at the `.end' pseudo-op
- From: Maciej W.Rozycki <macro at sourceware dot org>
- To: bfd-cvs at sourceware dot org
- Date: 22 Feb 2017 18:18:03 -0000
- Subject: [binutils-gdb] GAS: Consistently fix labels at the `.end' pseudo-op
https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=5ff6a06c215a5288787decfb933591afb5aa434d
commit 5ff6a06c215a5288787decfb933591afb5aa434d
Author: Maciej W. Rozycki <macro@imgtec.com>
Date: Fri Feb 17 20:30:55 2017 +0000
GAS: Consistently fix labels at the `.end' pseudo-op
Fix a functional regression with the `.end' pseudo-op, introduced with
commit ecb4347adecd ("Last take: approval for MIPS_STABS_ELF killing"),
<https://sourceware.org/ml/binutils/2002-06/msg00443.html>, and commit
dcd410fe1544 ("GNU as 2.14 on IRIX 6: crashes with shared libs"),
<https://sourceware.org/ml/binutils/2003-07/msg00415.html>, which caused
symbol values for labels placed between the end of a function's contents
and its terminating `.end' followed by one of the alignment pseudo-ops
to be different depending on whether either `-mdebug', or `-mno-pdr', or
neither of the command-line options is in effect, be it implied or
specified.
Given debug-label-end.s as follows and the `mips-linux' target we have:
$ cat debug-label-end.s
.text
.globl foo
.globl bar
.align 4, 0
.ent foo
foo:
nop
.aent bar
bar:
.insn
.end foo
.align 4, 0
.space 16
.globl baz
.ent baz
baz:
nop
.end baz
.align 4, 0
.space 16
$ as -o debug-label-end.o debug-label-end.s
$ readelf -s debug-label-end.o | grep bar
9: 00000004 0 FUNC GLOBAL DEFAULT 1 bar
$ as -mdebug -o debug-label-end.o debug-label-end.s
$ readelf -s debug-label-end.o | grep bar
9: 00000010 0 FUNC GLOBAL DEFAULT 1 bar
$ as -mno-pdr -o debug-label-end.o debug-label-end.s
$ readelf -s debug-label-end.o | grep bar
8: 00000010 0 FUNC GLOBAL DEFAULT 1 bar
$
The reason is the call to `md_flush_pending_output', which in the case
of `mips*-*-*' targets expands to `mips_emit_delays', which in turn
calls `mips_no_prev_insn', which calls `mips_clear_insn_labels', which
clears the list of outstanding labels. That list is in turn consulted
in `mips_align', called in the interpretation of alignment directives,
and the labels adjusted to the current location.
A call to `md_flush_pending_output' is only made from `s_mips_end' and
then only if `-mpdr' is in effect, which is the default for `*-*-linux*'
and some other `mips*-*-*' targets. A call to `md_flush_pending_output'
is never made from `ecoff_directive_end', which is used in place of
`s_mips_end' when `-mdebug' is in effect. Consequently if `-mno-pdr' or
`-mdebug' is in effect the list of outstanding labels makes it through
to any alignment directive that follows and the labels are differently
interpreted depending on the command-lines options used. And we want
code produced to be always the same.
Call `md_flush_pending_output' unconditionally then in `s_mips_end' and
add such a call from `ecoff_directive_end' as well, as long as the macro
is defined. While `ecoff_directive_end' is shared among targets, the
only one other than `mips*-*-*' actually using it is `alpha*-*-*' and it
does not define `md_flush_pending_output'. So the semantics isn't going
to change for it and neither it has to have its `s_alpha_end' updated
or have code in `ecoff_directive_end' conditionalized.
gas/
* ecoff.c (ecoff_directive_end) [md_flush_pending_output]: Call
`md_flush_pending_output'.
* config/tc-mips.c (s_mips_end) [md_flush_pending_output]: Call
`md_flush_pending_output' unconditionally.
* testsuite/gas/mips/debug-label-end-1.d: New test.
* testsuite/gas/mips/debug-label-end-2.d: New test.
* testsuite/gas/mips/debug-label-end-3.d: New test.
* testsuite/gas/mips/debug-label-end.s: New test source.
* testsuite/gas/mips/mips.exp: Run the new tests.
Diff:
---
gas/ChangeLog | 12 ++++++++++++
gas/config/tc-mips.c | 8 ++++----
gas/ecoff.c | 4 ++++
gas/testsuite/gas/mips/debug-label-end-1.d | 21 +++++++++++++++++++++
gas/testsuite/gas/mips/debug-label-end-2.d | 17 +++++++++++++++++
gas/testsuite/gas/mips/debug-label-end-3.d | 17 +++++++++++++++++
gas/testsuite/gas/mips/debug-label-end.s | 22 ++++++++++++++++++++++
gas/testsuite/gas/mips/mips.exp | 4 ++++
8 files changed, 101 insertions(+), 4 deletions(-)
diff --git a/gas/ChangeLog b/gas/ChangeLog
index 738083e..2b11805 100644
--- a/gas/ChangeLog
+++ b/gas/ChangeLog
@@ -1,3 +1,15 @@
+2017-02-22 Maciej W. Rozycki <macro@imgtec.com>
+
+ * ecoff.c (ecoff_directive_end) [md_flush_pending_output]: Call
+ `md_flush_pending_output'.
+ * config/tc-mips.c (s_mips_end) [md_flush_pending_output]: Call
+ `md_flush_pending_output' unconditionally.
+ * testsuite/gas/mips/debug-label-end-1.d: New test.
+ * testsuite/gas/mips/debug-label-end-2.d: New test.
+ * testsuite/gas/mips/debug-label-end-3.d: New test.
+ * testsuite/gas/mips/debug-label-end.s: New test source.
+ * testsuite/gas/mips/mips.exp: Run the new tests.
+
2017-02-22 Hans-Peter Nilsson <hp@axis.com>
* testsuite/gas/all/err-sizeof.s: Include cris*-*-* in the list of
diff --git a/gas/config/tc-mips.c b/gas/config/tc-mips.c
index d151b01..54b94be 100644
--- a/gas/config/tc-mips.c
+++ b/gas/config/tc-mips.c
@@ -19080,6 +19080,10 @@ s_mips_end (int x ATTRIBUTE_UNUSED)
cur_proc_ptr->func_end_sym = exp->X_add_symbol;
}
+#ifdef md_flush_pending_output
+ md_flush_pending_output ();
+#endif
+
/* Generate a .pdr section. */
if (!ECOFF_DEBUGGING && mips_flag_pdr)
{
@@ -19088,10 +19092,6 @@ s_mips_end (int x ATTRIBUTE_UNUSED)
expressionS exp;
char *fragp;
-#ifdef md_flush_pending_output
- md_flush_pending_output ();
-#endif
-
gas_assert (pdr_seg);
subseg_set (pdr_seg, 0);
diff --git a/gas/ecoff.c b/gas/ecoff.c
index 5c37312..608d72b 100644
--- a/gas/ecoff.c
+++ b/gas/ecoff.c
@@ -3025,6 +3025,10 @@ ecoff_directive_end (int ignore ATTRIBUTE_UNUSED)
frag_now),
(bfd_vma) 0, (symint_t) 0, (symint_t) 0);
+#ifdef md_flush_pending_output
+ md_flush_pending_output ();
+#endif
+
cur_proc_ptr = (proc_t *) NULL;
(void) restore_line_pointer (name_end);
diff --git a/gas/testsuite/gas/mips/debug-label-end-1.d b/gas/testsuite/gas/mips/debug-label-end-1.d
new file mode 100644
index 0000000..c158326
--- /dev/null
+++ b/gas/testsuite/gas/mips/debug-label-end-1.d
@@ -0,0 +1,21 @@
+#readelf: -s
+#name: MIPS ECOFF/PDR debug interaction with labels at .end 1
+#as: -32 -no-mdebug -mpdr
+#source: debug-label-end.s
+
+# Verify that .end finalizes any labels outstanding
+# where PDR debug generation is enabled, e.g.:
+# Num: Value Size Type Bind Vis Ndx Name
+# 7: 00000000 4 FUNC GLOBAL DEFAULT 1 foo
+# 8: 00000004 0 FUNC GLOBAL DEFAULT 1 bar
+# 9: 00000020 4 FUNC GLOBAL DEFAULT 1 baz
+# vs:
+# Num: Value Size Type Bind Vis Ndx Name
+# 7: 00000000 4 FUNC GLOBAL DEFAULT 1 foo
+# 8: 00000010 0 FUNC GLOBAL DEFAULT 1 bar
+# 9: 00000020 4 FUNC GLOBAL DEFAULT 1 baz
+#...
+ *[0-9]+: +0+000000 +4 +FUNC +GLOBAL +DEFAULT +[0-9]+ foo
+ *[0-9]+: +0+000004 +0 +FUNC +GLOBAL +DEFAULT +[0-9]+ bar
+ *[0-9]+: +0+000020 +4 +FUNC +GLOBAL +DEFAULT +[0-9]+ baz
+#pass
diff --git a/gas/testsuite/gas/mips/debug-label-end-2.d b/gas/testsuite/gas/mips/debug-label-end-2.d
new file mode 100644
index 0000000..ad36caf
--- /dev/null
+++ b/gas/testsuite/gas/mips/debug-label-end-2.d
@@ -0,0 +1,17 @@
+#readelf: -s
+#name: MIPS ECOFF/PDR debug interaction with labels at .end 2
+#as: -32 -mdebug -mno-pdr
+#source: debug-label-end.s
+#dump: debug-label-end-1.d
+
+# Verify that .end finalizes any labels outstanding
+# where ECOFF debug generation is enabled, e.g.:
+# Num: Value Size Type Bind Vis Ndx Name
+# 7: 00000000 4 FUNC GLOBAL DEFAULT 1 foo
+# 8: 00000004 0 FUNC GLOBAL DEFAULT 1 bar
+# 9: 00000020 4 FUNC GLOBAL DEFAULT 1 baz
+# vs:
+# Num: Value Size Type Bind Vis Ndx Name
+# 7: 00000000 4 FUNC GLOBAL DEFAULT 1 foo
+# 8: 00000010 0 FUNC GLOBAL DEFAULT 1 bar
+# 9: 00000020 4 FUNC GLOBAL DEFAULT 1 baz
diff --git a/gas/testsuite/gas/mips/debug-label-end-3.d b/gas/testsuite/gas/mips/debug-label-end-3.d
new file mode 100644
index 0000000..184583e
--- /dev/null
+++ b/gas/testsuite/gas/mips/debug-label-end-3.d
@@ -0,0 +1,17 @@
+#readelf: -s
+#name: MIPS ECOFF/PDR debug interaction with labels at .end 3
+#as: -32 -no-mdebug -mno-pdr
+#source: debug-label-end.s
+#dump: debug-label-end-1.d
+
+# Verify that .end finalizes any labels outstanding
+# where both ECOFF and PDR generation is disabled, e.g.:
+# Num: Value Size Type Bind Vis Ndx Name
+# 7: 00000000 4 FUNC GLOBAL DEFAULT 1 foo
+# 8: 00000004 0 FUNC GLOBAL DEFAULT 1 bar
+# 9: 00000020 4 FUNC GLOBAL DEFAULT 1 baz
+# vs:
+# Num: Value Size Type Bind Vis Ndx Name
+# 7: 00000000 4 FUNC GLOBAL DEFAULT 1 foo
+# 8: 00000010 0 FUNC GLOBAL DEFAULT 1 bar
+# 9: 00000020 4 FUNC GLOBAL DEFAULT 1 baz
diff --git a/gas/testsuite/gas/mips/debug-label-end.s b/gas/testsuite/gas/mips/debug-label-end.s
new file mode 100644
index 0000000..caf4dd1
--- /dev/null
+++ b/gas/testsuite/gas/mips/debug-label-end.s
@@ -0,0 +1,22 @@
+ .text
+
+ .globl foo
+ .globl bar
+ .align 4, 0
+ .ent foo
+foo:
+ nop
+ .aent bar
+bar:
+ .insn
+ .end foo
+ .align 4, 0
+ .space 16
+
+ .globl baz
+ .ent baz
+baz:
+ nop
+ .end baz
+ .align 4, 0
+ .space 16
diff --git a/gas/testsuite/gas/mips/mips.exp b/gas/testsuite/gas/mips/mips.exp
index 8a9f9f1..bef7106 100644
--- a/gas/testsuite/gas/mips/mips.exp
+++ b/gas/testsuite/gas/mips/mips.exp
@@ -1794,6 +1794,10 @@ if { [istarget mips*-*-vxworks*] } {
run_dump_test_arches "isa-override-1" "" [mips_arch_list_matching mips1]
run_list_test_arches "isa-override-2" "-32" [mips_arch_list_matching mips1]
+ run_dump_test "debug-label-end-1"
+ run_dump_test "debug-label-end-2"
+ run_dump_test "debug-label-end-3"
+
run_dump_test_arches "r6" [mips_arch_list_matching mips32r6]
if $has_newabi {
run_dump_test_arches "r6-n32" [mips_arch_list_matching mips64r6]