/* PLT trampolines. s390 version. Copyright (C) 2016 Free Software Foundation, Inc. This file is part of the GNU C Library. The GNU C Library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. The GNU C Library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with the GNU C Library; if not, see . */ /* This code is used in dl-runtime.c to call the `fixup' function and then redirect to the address it returns. */ /* The PLT stubs will call _dl_runtime_resolve/_dl_runtime_profile * with the following linkage: * r2 - r6 : parameter registers * f0, f2 : floating point parameter registers * v24, v26, v28, v30, v25, v27, v29, v31 : vector parameter registers * 24(r15), 28(r15) : PLT arguments PLT1, PLT2 * 96(r15) : additional stack parameters * The normal clobber rules for function calls apply: * r0 - r5 : call clobbered * r6 - r13 : call saved * r14 : return address (call clobbered) * r15 : stack pointer (call saved) * f4, f6 : call saved * f0 - f3, f5, f7 - f15 : call clobbered * v0 - v3, v5, v7 - v15 : bytes 0-7 overlap with fprs: call clobbered bytes 8-15: call clobbered * v4, v6 : bytes 0-7 overlap with f4, f6: call saved bytes 8-15: call clobbered * v16 - v31 : call clobbered */ .globl _dl_runtime_resolve .type _dl_runtime_resolve, @function cfi_startproc .align 16 _dl_runtime_resolve: stm %r2,%r5,32(%r15) # save registers cfi_offset (r2, -64) cfi_offset (r3, -60) cfi_offset (r4, -56) cfi_offset (r5, -52) std %f0,56(%r15) cfi_offset (f0, -40) std %f2,64(%r15) cfi_offset (f2, -32) st %r14,8(%r15) cfi_offset (r14, -88) lr %r0,%r15 lm %r2,%r3,24(%r15) # load args saved by PLT #ifdef RESTORE_VRS ahi %r15,-224 # create stack frame cfi_adjust_cfa_offset (224) .machine push .machine "z13" .machinemode "zarch_nohighgprs" vstm %v24,%v31,96(%r15) # store call-clobbered vr arguments cfi_offset (v24, -224) cfi_offset (v25, -208) cfi_offset (v26, -192) cfi_offset (v27, -176) cfi_offset (v28, -160) cfi_offset (v29, -144) cfi_offset (v30, -128) cfi_offset (v31, -112) .machine pop #else ahi %r15,-96 # create stack frame cfi_adjust_cfa_offset (96) #endif st %r0,0(%r15) # write backchain basr %r1,0 0: l %r14,1f-0b(%r1) bas %r14,0(%r14,%r1) # call _dl_fixup lr %r1,%r2 # function addr returned in r2 #ifdef RESTORE_VRS .machine push .machine "z13" .machinemode "zarch_nohighgprs" vlm %v24,%v31,96(%r15) # restore vector registers .machine pop aghi %r15,224 # remove stack frame cfi_adjust_cfa_offset (-224) #else ahi %r15,96 # remove stack frame cfi_adjust_cfa_offset (-96) #endif l %r14,8(15) # restore registers ld %f0,56(%r15) ld %f2,64(%r15) lm %r2,%r5,32(%r15) br %r1 1: .long _dl_fixup - 0b cfi_endproc .size _dl_runtime_resolve, .-_dl_runtime_resolve #ifndef PROF .globl _dl_runtime_profile .type _dl_runtime_profile, @function cfi_startproc .align 16 _dl_runtime_profile: st %r12,12(%r15) # r12 is used as backup of r15 cfi_offset (r12, -84) st %r14,16(%r15) cfi_offset (r14, -80) lr %r12,%r15 # backup stack pointer cfi_def_cfa_register (12) ahi %r15,-264 # create stack frame: # 96 + sizeof(La_s390_32_regs) st %r12,0(%r15) # save backchain stm %r2,%r6,96(%r15) # save registers cfi_offset (r2, -264) # + r6 needed as arg for cfi_offset (r3, -260) # _dl_profile_fixup cfi_offset (r4, -256) cfi_offset (r5, -252) cfi_offset (r6, -248) std %f0,120(%r15) cfi_offset (f0, -240) std %f2,128(%r15) cfi_offset (f2, -232) #ifdef RESTORE_VRS .machine push .machine "z13" .machinemode "zarch_nohighgprs" vstm %v24,%v31,136(%r15) # store call-clobbered vr arguments cfi_offset (v24, -224) cfi_offset (v25, -208) cfi_offset (v26, -192) cfi_offset (v27, -176) cfi_offset (v28, -160) cfi_offset (v29, -144) cfi_offset (v30, -128) cfi_offset (v31, -112) .machine pop #endif lm %r2,%r3,24(%r12) # load arguments saved by PLT lr %r4,%r14 # return address as third parameter basr %r1,0 0: l %r14,6f-0b(%r1) la %r5,96(%r15) # pointer to struct La_s390_32_regs la %r6,20(%r12) # long int * framesize bas %r14,0(%r14,%r1) # call resolver lr %r1,%r2 # function addr returned in r2 ld %f0,120(%r15) # restore call-clobbered arg fprs ld %f2,128(%r15) #ifdef RESTORE_VRS .machine push .machine "z13" .machinemode "zarch_nohighgprs" vlm %v24,%v31,136(%r15) # restore call-clobbered arg vrs .machine pop #endif icm %r0,15,20(%r12) # load & test framesize jnm 2f lm %r2,%r6,96(%r15) # framesize < 0 means no pltexit call # so we can do a tail call without # copying the arg overflow area lr %r15,%r12 # remove stack frame cfi_def_cfa_register (15) l %r14,16(%r15) # restore registers l %r12,12(%r15) br %r1 # tail-call to the resolved function cfi_def_cfa_register (12) 2: la %r4,96(%r15) # pointer to struct La_s390_32_regs st %r4,32(%r12) jz 4f # framesize == 0 ? ahi %r0,7 # align framesize to 8 lhi %r2,-8 nr %r0,%r2 slr %r15,%r0 # make room for framesize bytes st %r12,0(%r15) # save backchain la %r2,96(%r15) la %r3,96(%r12) srl %r0,3 3: mvc 0(8,%r2),0(%r3) # copy additional parameters la %r2,8(%r2) la %r3,8(%r3) brct %r0,3b 4: lm %r2,%r6,0(%r4) # load register parameters basr %r14,%r1 # call resolved function stm %r2,%r3,40(%r12) # store return values r2, r3, f0 std %f0,48(%r12) # to struct La_s390_32_retval #ifdef RESTORE_VRS .machine push .machine "z13" vst %v24,56(%r12) # store return value v24 .machine pop #endif lm %r2,%r4,24(%r12) # r2, r3: load arguments saved by PLT # r4: pointer to struct La_s390_32_regs basr %r1,0 5: l %r14,7f-5b(%r1) la %r5,40(%r12) # pointer to struct La_s390_32_retval bas %r14,0(%r14,%r1) # call _dl_call_pltexit lr %r15,%r12 # remove stack frame cfi_def_cfa_register (15) l %r14,16(%r15) # restore registers l %r12,12(%r15) lm %r2,%r3,40(%r15) # restore return values ld %f0,48(%r15) #ifdef RESTORE_VRS .machine push .machine "z13" vl %v24,56(%r15) # restore return value v24 .machine pop #endif br %r14 6: .long _dl_profile_fixup - 0b 7: .long _dl_call_pltexit - 5b cfi_endproc .size _dl_runtime_profile, .-_dl_runtime_profile #endif