Any good rules of pratice about branching insn into the delay slot of another one?
Hello all,
This question about latest test related to some glibc clone().
This patch:
# diff -Nau clone.S.orig2 clone.S.New4 --- clone.S.orig2 2006-03-24 09:11:27.000000000 +0000 +++ clone.S.New4 2006-03-31 17:42:25.000000000 +0000 @@ -45,7 +45,31 @@
.text
ENTRY(__clone)
+ /* this ENTRY() macro do: stw rp, -20(sp)
+ and "FIXME: I have no idea how profiling works on hppa." */
+ /* Sanity check arguments. */
+ comib,= 0, %arg0, .Larg_error /* no NULL function pointers */
+ nop
+ comib,<>,n 0, %arg1, .Lno_arg_error /* no NULL stack pointers */
+ nop
+
+.Larg_error:
+ /* Create a stack frame */
+/* stwm %r3, 64(%sp) */
+ ldo 64(%sp), %sp
+ /* Set errno */
+ bl __syscall_error, %rp
+ ldi EINVAL, %arg0
+
+ /* Return after setting errno */
+ /* Restore rp from ENTRY() */
+ ldw -84(%sp), %rp
+ bv %r0(%rp)
+/* ldwm -64(%sp), %r3 */
+ ldo -64(%sp), %sp
+
+.Lno_arg_error:
/* Save the fn ptr and arg on the new stack. */
stwm %arg0, 64(%arg1)
stw %arg3, -60(%arg1)
@@ -75,8 +99,10 @@
ldi -4096, %r1
comclr,>>= %r1, %ret0, %r0 /* Note: unsigned compare. */
b,n .Lerror+ nop
comib,=,n 0, %ret0, thread_start
+ nop /* to avoid bv in the delay slot? */
/* Successful return from the parent
No need to restore the PIC register,
@@ -94,10 +120,12 @@
#endif
/* Set errno */
copy %ret0, %r3
- b __syscall_error
+ bl __syscall_error, %rp
sub %r0, %ret0, %arg0
copy %r3, %ret0
/* Return after setting errno */
+ /* Restore rp from ENTRY() */
+ ldw -84(%sp), %rp
bv %r0(%rp)
ldwm -64(%sp), %r3====<>====
seems to works seems to be ok:
# grep Err glibc-2.3.6-4.3.1 make[3]: *** [/CAD/parisc-linux/Dpkg/dpkg-work/glibc-2.3.6/build-tree/hppa-libc/localedata/sort-test.out] Error 1 make[2]: *** [localedata/tests] Error 2 make[3]: *** [/CAD/parisc-linux/Dpkg/dpkg-work/glibc-2.3.6/build-tree/hppa-libc/math/test-float.out] Error 1 make[3]: *** [/CAD/parisc-linux/Dpkg/dpkg-work/glibc-2.3.6/build-tree/hppa-libc/math/test-double.out] Error 1 make[3]: *** [/CAD/parisc-linux/Dpkg/dpkg-work/glibc-2.3.6/build-tree/hppa-libc/math/test-idouble.out] Error 1 make[2]: *** [math/tests] Error 2 make[3]: *** [/CAD/parisc-linux/Dpkg/dpkg-work/glibc-2.3.6/build-tree/hppa-libc/posix/tst-rxspencer.out] Error 139 make[3]: [/CAD/parisc-linux/Dpkg/dpkg-work/glibc-2.3.6/build-tree/hppa-libc/posix/annexc.out] Error 1 (ignored) make[2]: *** [posix/tests] Error 2 make[3]: *** [/CAD/parisc-linux/Dpkg/dpkg-work/glibc-2.3.6/build-tree/hppa-libc/linuxthreads/tst-attr1.out] Error 1 make[2]: *** [linuxthreads/tests] Error 2 make[3]: *** [/CAD/parisc-linux/Dpkg/dpkg-work/glibc-2.3.6/build-tree/hppa-libc/rt/tst-timer.out] Error 137 make[3]: *** [/CAD/parisc-linux/Dpkg/dpkg-work/glibc-2.3.6/build-tree/hppa-libc/rt/tst-aio4.out] Error 1 make[3]: *** [/CAD/parisc-linux/Dpkg/dpkg-work/glibc-2.3.6/build-tree/hppa-libc/rt/tst-timer4.out] Error 1 make[2]: *** [rt/tests] Error 2 make[3]: *** [/CAD/parisc-linux/Dpkg/dpkg-work/glibc-2.3.6/build-tree/hppa-libc/elf/tst-execstack-needed.out] Error 1 make[2]: *** [elf/tests] Error 2 make[1]: *** [check] Error 2
(well doesn't seems to introduce regression in test)
OTOH if I remove the nop I added in delay slot of 'b,n .Lerror' and 'comib,=,n 0, %ret0, thread_start' i.e. rm hunk:
@@ -75,8 +99,10 @@
ldi -4096, %r1
comclr,>>= %r1, %ret0, %r0 /* Note: unsigned compare. */
b,n .Lerror+ nop
comib,=,n 0, %ret0, thread_start
+ nop /* to avoid bv in the delay slot? */
/* Successful return from the parent
No need to restore the PIC register,
test became very regressive:
# grep Err glibc-2.3.6-4.3.2 make[3]: *** [/CAD/parisc-linux/Dpkg/dpkg-work/glibc-2.3.6/build-tree/hppa-libc/iconvdata/tst-iconv4.out] Error 1 make[2]: *** [iconvdata/tests] Error 2 make[3]: *** [/CAD/parisc-linux/Dpkg/dpkg-work/glibc-2.3.6/build-tree/hppa-libc/localedata/sort-test.out] Error 1 make[2]: *** [localedata/tests] Error 2 make[3]: *** [/CAD/parisc-linux/Dpkg/dpkg-work/glibc-2.3.6/build-tree/hppa-libc/math/test-float.out] Error 1 make[3]: *** [/CAD/parisc-linux/Dpkg/dpkg-work/glibc-2.3.6/build-tree/hppa-libc/math/test-double.out] Error 1 make[3]: *** [/CAD/parisc-linux/Dpkg/dpkg-work/glibc-2.3.6/build-tree/hppa-libc/math/test-idouble.out] Error 1 make[2]: *** [math/tests] Error 2 make[3]: *** [/CAD/parisc-linux/Dpkg/dpkg-work/glibc-2.3.6/build-tree/hppa-libc/stdio-common/tst-rndseek.out] Error 1 make[2]: *** [stdio-common/tests] Error 2 make[3]: *** [/CAD/parisc-linux/Dpkg/dpkg-work/glibc-2.3.6/build-tree/hppa-libc/libio/bug-mmap-fflush.out] Error 1 make[2]: *** [libio/tests] Error 2 make[3]: *** [/CAD/parisc-linux/Dpkg/dpkg-work/glibc-2.3.6/build-tree/hppa-libc/posix/tst-chmod.out] Error 1 make[3]: *** [/CAD/parisc-linux/Dpkg/dpkg-work/glibc-2.3.6/build-tree/hppa-libc/posix/bug-regex24.out] Error 1 make[3]: *** [/CAD/parisc-linux/Dpkg/dpkg-work/glibc-2.3.6/build-tree/hppa-libc/posix/tst-regex2.out] Error 1 make[3]: *** [/CAD/parisc-linux/Dpkg/dpkg-work/glibc-2.3.6/build-tree/hppa-libc/posix/tst-rxspencer.out] Error 139 make[3]: [/CAD/parisc-linux/Dpkg/dpkg-work/glibc-2.3.6/build-tree/hppa-libc/posix/annexc.out] Error 1 (ignored) make[2]: *** [posix/tests] Error 2 make[3]: *** [/CAD/parisc-linux/Dpkg/dpkg-work/glibc-2.3.6/build-tree/hppa-libc/linuxthreads/tst-attr1.out] Error 1 make[2]: *** [linuxthreads/tests] Error 2 make[3]: *** [/CAD/parisc-linux/Dpkg/dpkg-work/glibc-2.3.6/build-tree/hppa-libc/rt/tst-clock.out] Error 1 make[3]: *** [/CAD/parisc-linux/Dpkg/dpkg-work/glibc-2.3.6/build-tree/hppa-libc/rt/tst-timer.out] Error 139 make[3]: *** [/CAD/parisc-linux/Dpkg/dpkg-work/glibc-2.3.6/build-tree/hppa-libc/rt/tst-aio4.out] Error 1 make[3]: *** [/CAD/parisc-linux/Dpkg/dpkg-work/glibc-2.3.6/build-tree/hppa-libc/rt/tst-aio5.out] Error 1 make[3]: *** [/CAD/parisc-linux/Dpkg/dpkg-work/glibc-2.3.6/build-tree/hppa-libc/rt/tst-aio6.out] Error 1 make[3]: *** [/CAD/parisc-linux/Dpkg/dpkg-work/glibc-2.3.6/build-tree/hppa-libc/rt/tst-timer3.out] Error 1 make[3]: *** [/CAD/parisc-linux/Dpkg/dpkg-work/glibc-2.3.6/build-tree/hppa-libc/rt/tst-timer4.out] Error 1 make[2]: *** [rt/tests] Error 2 make[3]: *** [/CAD/parisc-linux/Dpkg/dpkg-work/glibc-2.3.6/build-tree/hppa-libc/elf/tst-tls13.out] Error 1 make[3]: *** [/CAD/parisc-linux/Dpkg/dpkg-work/glibc-2.3.6/build-tree/hppa-libc/elf/tst-execstack-prog.out] Error 1 make[2]: *** [elf/tests] Error 2 make[1]: *** [check] Error 2
Thanks in advance for advise,
Joel
_______________________________________________
parisc-linux mailing list
[email protected]
http://lists.parisc-linux.org/mailman/listinfo/parisc-linux
Quoted 1 line
This question about latest test related to some glibc
clone().
why don't you try to step through the code with gdb (using stepi) and see the sequence of insns that get executed in the different cases?
randolph
_______________________________________________
parisc-linux mailing list
[email protected]
http://lists.parisc-linux.org/mailman/listinfo/parisc-linux