diff options
Diffstat (limited to 'libc/sysdeps/s390/s390-64/dl-trampoline.S')
| -rw-r--r-- | libc/sysdeps/s390/s390-64/dl-trampoline.S | 70 |
1 files changed, 38 insertions, 32 deletions
diff --git a/libc/sysdeps/s390/s390-64/dl-trampoline.S b/libc/sysdeps/s390/s390-64/dl-trampoline.S index 81144a0ca..29d374f86 100644 --- a/libc/sysdeps/s390/s390-64/dl-trampoline.S +++ b/libc/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 |