Ralf Baechle wrote:
> Below little test case demonstrates a gas bug that results in swapping
> of the two branch instructions and use of bogus destination addresses
> for the first of the two branches.
>
> [ralf@lappi tmp]$ cat s.s
> 1: beqzl $2, 1b
> beq $4, $5, 1b
> [ralf@lappi tmp]$ mips-linux-as -mips2 -o s.o s.s
> [ralf@lappi tmp]$ mips-linux-objdump -d s.o
>
> s.o: file format elf32-tradbigmips
>
> Disassembly of section .text:
>
> 00000000 <.text>:
> 0: 1085ffff beq a0,a1,0x0
> 4: 00000000 nop
> 8: 50400000 beqzl v0,0xc
> c: 00000000 nop
I applied the appended patch. Daniel, I think this should also go
in the branch.
Thiemo
/gas/ChangeLog
2004-08-18 Thiemo Seufer <seufer@xxxxxxxxxxxxxxxxxxxxxxxx>
* config/tc-mips.c (append_insn): Handle delay slots in branch likely
correctly.
/gas/testsuite/ChangeLog
2004-08-18 Thiemo Seufer <seufer@xxxxxxxxxxxxxxxxxxxxxxxx>
* gas/mips/branch-swap.s: New testcase.
* gas/mips/branch-swap.d: New testcase.
* gas/mips/mips.exp: Run the testcase.
--- gas/config/tc-mips.c.old 2004-05-17 21:36:10.000000000 +0200
+++ gas/config/tc-mips.c 2004-08-17 20:00:43.000000000 +0200
@@ -2708,6 +2708,7 @@ append_insn (struct mips_cl_insn *ip, ex
prev_insn_reloc_type[1] = BFD_RELOC_UNUSED;
prev_insn_reloc_type[2] = BFD_RELOC_UNUSED;
prev_insn_extended = 0;
+ prev_insn_is_delay_slot = 1;
}
else
{
--- gas/testsuite/gas/mips/mips.exp.old 2004-08-17 22:50:38.000000000 +0200
+++ gas/testsuite/gas/mips/mips.exp 2004-08-18 14:53:43.000000000 +0200
@@ -429,6 +429,7 @@ if { [istarget mips*-*-*] } then {
run_dump_test_arches "branch-misc-1" [mips_arch_list_matching mips1]
run_list_test_arches "branch-misc-2" "-32 -non_shared" [mips_arch_list_matching mips1]
run_list_test_arches "branch-misc-2pic" "-32 -call_shared" [mips_arch_list_matching mips1]
+ run_dump_test "branch-swap"
if $ilocks {
run_dump_test "div-ilocks"
--- gas/testsuite/gas/mips/branch-swap.s.old 1970-01-01 01:00:00.000000000 +0100
+++ gas/testsuite/gas/mips/branch-swap.s 2004-08-17 22:52:50.000000000 +0200
@@ -0,0 +1,9 @@
+ .set push
+ .set mips2
+1: beqzl $2, 1b
+ b 1b
+foo: beqzl $2, foo
+ b foo
+
+ .set pop
+ .space 8
--- gas/testsuite/gas/mips/branch-swap.d.old 1970-01-01 01:00:00.000000000 +0100
+++ gas/testsuite/gas/mips/branch-swap.d 2004-08-17 22:57:36.000000000 +0200
@@ -0,0 +1,20 @@
+#as: -march=mips2
+#objdump: -dr
+#name: MIPS branch-swap
+
+.*: file format .*mips.*
+
+Disassembly of section \.text:
+
+00000000 <foo-0x10>:
+ 0: 5040ffff beqzl v0,0 <foo-0x10>
+ 4: 00000000 nop
+ 8: 1000fffd b 0 <foo-0x10>
+ c: 00000000 nop
+
+00000010 <foo>:
+ 10: 5040ffff beqzl v0,10 <foo>
+ 14: 00000000 nop
+ 18: 1000fffd b 10 <foo>
+ 1c: 00000000 nop
+ \.\.\.
