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-rw-r--r--ChangeLog6
-rw-r--r--sysdeps/s390/s390-64/dl-trampoline.S70
2 files changed, 44 insertions, 32 deletions
diff --git a/ChangeLog b/ChangeLog
index c18b327de2..477ec3b07e 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+2013-02-18 Andreas Krebbel <Andreas.Krebbel@de.ibm.com>
+
+ * sysdeps/s390/s390-64/dl-trampoline.S (_dl_runtime_resolve):
+ Syntactic changes only.
+ (_dl_runtime_profile): Do a tail-call to the resolved function.
+
2013-02-17 Joseph Myers <joseph@codesourcery.com>
[BZ #13550]
diff --git a/sysdeps/s390/s390-64/dl-trampoline.S b/sysdeps/s390/s390-64/dl-trampoline.S
index 81144a0cae..29d374f868 100644
--- a/sysdeps/s390/s390-64/dl-trampoline.S
+++ b/sysdeps/s390/s390-64/dl-trampoline.S
@@ -1,4 +1,4 @@
-/* PLT trampolines. s390 version.
+/* PLT trampolines. s390x version.
Copyright (C) 2005-2013 Free Software Foundation, Inc.
This file is part of the GNU C Library.
@@ -20,8 +20,8 @@
* with the following linkage:
* r2 - r6 : parameter registers
* f0, f2, f4, f6 : floating point parameter registers
- * 24(r15), 28(r15) : PLT arguments PLT1, PLT2
- * 96(r15) : additional stack parameters
+ * 48(r15), 56(r15) : PLT arguments PLT1, PLT2
+ * 160(r15) : additional stack parameters
* The normal clobber rules for function calls apply:
* r0 - r5 : call clobbered
* r6 - r13 : call saved
@@ -39,21 +39,21 @@
cfi_startproc
.align 16
_dl_runtime_resolve:
- stmg 2,5,64(15) # save registers
- stg 14,96(15)
+ stmg %r2,%r5,64(15) # save call-clobbered argument registers
+ stg %r14,96(15)
cfi_offset (r14, -64)
- lgr 0,15 # create stack frame
- aghi 15,-160
+ lgr %r0,%r15
+ aghi %r15,-160 # create stack frame
cfi_adjust_cfa_offset (160)
- stg 0,0(15)
- lmg 2,3,208(15) # load args saved by PLT
- brasl 14,_dl_fixup # call fixup
- lgr 1,2 # function addr returned in r2
- aghi 15,160 # remove stack frame
+ stg %r0,0(%r15) # write backchain
+ lmg %r2,%r3,208(%r15)# load args saved by PLT
+ brasl %r14,_dl_fixup # call fixup
+ lgr %r1,%r2 # function addr returned in r2
+ aghi %r15,160 # remove stack frame
cfi_adjust_cfa_offset (-160)
- lg 14,96(15) # restore registers
- lmg 2,5,64(15)
- br 1
+ lg %r14,96(15) # restore registers
+ lmg %r2,%r5,64(15)
+ br %r1
cfi_endproc
.size _dl_runtime_resolve, .-_dl_runtime_resolve
@@ -64,13 +64,12 @@ _dl_runtime_resolve:
cfi_startproc
.align 16
_dl_runtime_profile:
- stmg %r2,%r6,64(%r15) # save registers
- std %f0,104(%r15)
- std %f2,112(%r15)
+ stmg %r2,%r6,64(%r15) # save call-clobbered arg regs
+ std %f0,104(%r15) # + r6 needed as arg for
+ std %f2,112(%r15) # _dl_profile_fixup
std %f4,120(%r15)
std %f6,128(%r15)
- stg %r6,16(%r15)
- stg %r12,24(%r15)
+ stg %r12,24(%r15) # r12 is used as backup of r15
stg %r14,32(%r15)
cfi_offset (r6, -96)
cfi_offset (f0, -56)
@@ -79,10 +78,10 @@ _dl_runtime_profile:
cfi_offset (f6, -32)
cfi_offset (r12, -136)
cfi_offset (r14, -128)
- lgr %r12,%r15 # create stack frame
+ lgr %r12,%r15 # backup stack pointer
cfi_def_cfa_register (12)
- aghi %r15,-160
- stg %r12,0(%r15)
+ aghi %r15,-160 # create stack frame
+ stg %r12,0(%r15) # save backchain
lmg %r2,%r3,48(%r12) # load arguments saved by PLT
lgr %r4,%r14 # return address as third parameter
la %r5,64(%r12) # pointer to struct La_s390_32_regs
@@ -92,18 +91,19 @@ _dl_runtime_profile:
lg %r0,40(%r12) # load framesize
ltgr %r0,%r0
jnm 1f
- lmg %r2,%r6,64(%r12)
- ld %f0,104(%r12)
- ld %f2,112(%r12)
+
+ lmg %r2,%r6,64(%r12) # framesize < 0 means no pltexit call
+ ld %f0,104(%r12) # so we can do a tail call without
+ ld %f2,112(%r12) # copying the arg overflow area
ld %f4,120(%r12)
ld %f6,128(%r12)
- basr %r14,%r1 # call resolved function
-0: lgr %r15,%r12 # remove stack frame
+
+ lgr %r15,%r12 # remove stack frame
cfi_def_cfa_register (15)
lg %r14,32(%r15) # restore registers
lg %r12,24(%r15)
- lg %r6,16(%r15)
- br %r14
+ br %r1 # tail-call to resolved function
+
cfi_def_cfa_register (12)
1: jz 4f # framesize == 0 ?
aghi %r0,7 # align framesize to 8
@@ -118,7 +118,7 @@ _dl_runtime_profile:
la %r3,8(%r3)
brctg %r0,3b
4: lmg %r2,%r6,64(%r12) # load register parameters
- ld %f0,104(%r12)
+ ld %f0,104(%r12) # restore call-clobbered arg regs
ld %f2,112(%r12)
ld %f4,120(%r12)
ld %f6,128(%r12)
@@ -129,7 +129,13 @@ _dl_runtime_profile:
la %r4,32(%r12) # pointer to struct La_s390_32_regs
la %r5,72(%r12) # pointer to struct La_s390_32_retval
brasl %r14,_dl_call_pltexit
- j 0b
+
+ lgr %r15,%r12 # remove stack frame
+ cfi_def_cfa_register (15)
+ lg %r14,32(%r15) # restore registers
+ lg %r12,24(%r15)
+ br %r14
+
cfi_endproc
.size _dl_runtime_profile, .-_dl_runtime_profile
#endif