PR25333, GAS is slow processing -fdebug-types-sections

gas needs to build lists of sections for each group.  This arranges to
build the lists earlier, so they can be used when looking for sections
that belong to a group.  Using the section hash table to find sections
by name, then by group isn't efficient when there are numerous groups
with the same section names.  Using a hash table to quickly find a
group, then searching by section name on a list for the group results
in a 100-fold speed improvement assembling the testcase in this PR.

To reduce the number of times we traverse the section list, the patch
also moves some processing done in elf_adjust_symtab for linked-to
section, to elf_frob_file.  This requires a testsuite change because
processing will stop before elf_frob_file if there is a parse error in
section21.s, ie. you'll only get the "junk at end of line" error, not
the "undefined linked-to symbol" errors.

	PR 25333
	* config/obj-elf.c (struct group_list, groups): Move earlier.
	(match_section): New function, extracted from..
	(get_section_by_match): ..here.
	(free_section_idx): Move earlier.
	(group_section_find, group_section_insert): New functions.
	(change_section): Use the above.
	(elf_set_group_name): New function.
	(obj_elf_attach_to_group): Use elf_set_group_name.
	(set_additional_section_info): Handle linked_to_symbol_name and
	stabs code, extracted from..
	(adjust_stab_sections): ..here,..
	(build_additional_section_info): ..and here.
	(elf_adjust_symtab): Don't call build_additional_section_info.
	(elf_frob_file): Adjust.
	* config/obj-elf.h (elf_set_group_name): Declare.
	* config/tc-xtensa.c (cache_literal_section): Use elf_set_group_name.
	(xtensa_make_property_section): Likewise.
	* testsuite/gas/elf/attach-1.d: Stricter group section matching,
	and changed group section ordering.
	* testsuite/gas/elf/attach-2.d: Stricter group section matching.
	* testsuite/gas/elf/attach-2.s: Provide section bar type.
	* testsuite/gas/elf/elf.exp: Run attach-2.
	* testsuite/gas/elf/section21.l: Update.
	* testsuite/gas/elf/section21.s: Don't check for a parse error.

6 files changed, 15 insertions, 21 deletions

diff --git a/gas/testsuite/gas/elf/attach-1.d b/gas/testsuite/gas/elf/attach-1.d
index 053783e..b6b76f5 100644
--- a/gas/testsuite/gas/elf/attach-1.d
+++ b/gas/testsuite/gas/elf/attach-1.d
@@ -3,9 +3,9 @@
 #source: attach-1.s
 
 #...
-group section \[    1\] `\.group' \[foo\.group\] contains . sections:
+group section \[    1\] `\.group' \[foo\.group\] contains [24] sections:
    \[Index\]    Name
-   \[    .\]   .*
-   \[    .\]   foo
-#pass
-
+.* foo
+.* (\.text|P)
+#?.* \.xt\.prop
+#?.* \.rela\.xt\.prop
diff --git a/gas/testsuite/gas/elf/attach-2.d b/gas/testsuite/gas/elf/attach-2.d
index 4aa5211..68a1aab 100644
--- a/gas/testsuite/gas/elf/attach-2.d
+++ b/gas/testsuite/gas/elf/attach-2.d
@@ -1,11 +1,11 @@
 #readelf: --section-groups
-#name: Attaching a section to a non-existant group
+#name: Attaching a section to group defined later
 #source: attach-2.s
 
 #...
-group section \[    1\] `\.group' \[foo\.group\] contains 2 sections:
+group section \[    1\] `\.group' \[foo\.group\] contains [24] sections:
    \[Index\]    Name
-   \[    .\]   bar
-   \[    .\]   foo
-#pass
-
+.* bar
+.* foo
+#?.* \.xt\.prop
+#?.* \.rela\.xt\.prop
diff --git a/gas/testsuite/gas/elf/attach-2.s b/gas/testsuite/gas/elf/attach-2.s
index 4a5663f..d62a81b 100644
--- a/gas/testsuite/gas/elf/attach-2.s
+++ b/gas/testsuite/gas/elf/attach-2.s
@@ -1,9 +1,9 @@
-	.section bar
+	.section bar, "ax", %progbits
 	.nop
 	.attach_to_group foo.group
 	
 	.section foo, "G", %note , foo.group
 	.word 0
 
-	.section bar
+	.section bar, "ax", %progbits
 	.nop
diff --git a/gas/testsuite/gas/elf/elf.exp b/gas/testsuite/gas/elf/elf.exp
index e03dc2b..c828c3a 100644
--- a/gas/testsuite/gas/elf/elf.exp
+++ b/gas/testsuite/gas/elf/elf.exp
@@ -149,6 +149,7 @@ if { [is_elf_format] } then {
     run_dump_test "group3"
 
     run_dump_test "attach-1"
+    run_dump_test "attach-2"
     run_dump_test "attach-err"
 
     switch -glob $target_triplet {
diff --git a/gas/testsuite/gas/elf/section21.l b/gas/testsuite/gas/elf/section21.l
index 53f0415..b4d1283 100644
--- a/gas/testsuite/gas/elf/section21.l
+++ b/gas/testsuite/gas/elf/section21.l
@@ -1,5 +1,3 @@
 [^:]*: Assembler messages:
-[^:]*:11: Error: junk at end of line, first unrecognized character is `f'
-#...
 [^:]*: Error: undefined linked-to symbol `bar' on section `__patchable_function_entries'
 [^:]*: Error: undefined linked-to symbol `foo' on section `__patchable_function_entries'
diff --git a/gas/testsuite/gas/elf/section21.s b/gas/testsuite/gas/elf/section21.s
index ae5f848..e874154 100644
--- a/gas/testsuite/gas/elf/section21.s
+++ b/gas/testsuite/gas/elf/section21.s
@@ -2,14 +2,9 @@
 	.dc.a	.LPFE1
 	.text
 .LPFE1:
-	.byte 0
+	.dc.a 0
 	.section __patchable_function_entries,"awo",%progbits,foo
 	.dc.a	.LPFE2
 	.text
 .LPFE2:
 	.dc.a foo
-	.section __patchable_function_entries,"awo",%progbits,1foo
-	.dc.a	.LPFE3
-	.text
-.LPFE3:
-	.byte 0