ceph/src/boost/libs/context/src/asm/make_ppc64_sysv_macho_gas.S

   1 /*
   2             Copyright Oliver Kowalke 2009.
   3    Distributed under the Boost Software License, Version 1.0.
   4       (See accompanying file LICENSE_1_0.txt or copy at
   5           http://www.boost.org/LICENSE_1_0.txt)
   6 */
   7
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  67
  68 .text
  69 .globl _make_fcontext
  70 _make_fcontext:
  71     ; save return address into R6
  72     mflr  r6
  73
  74     ; first arg of make_fcontext() == top address of context-function
  75     ; shift address in R3 to lower 16 byte boundary
  76     clrrwi  r3, r3, 4
  77
  78     ; reserve space for context-data on context-stack
  79     ; including 64 byte of linkage + parameter area (R1  16 == 0)
  80     subi  r3, r3, 248
  81
  82     ; third arg of make_fcontext() == address of context-function
  83     stw  r5, 176(r3)
  84
  85     ; set back-chain to zero
  86     li   %r0, 0
  87     std  %r0, 184(%r3)
  88
  89     ; compute address of returned transfer_t
  90     addi %r0, %r3, 232
  91     mr   %r4, %r0
  92     std  %r4, 152(%r3)
  93
  94     ; load LR
  95     mflr  r0
  96     ; jump to label 1
  97     bl  l1
  98 l1:
  99     ; load LR into R4
 100     mflr  r4
 101     ; compute abs address of label finish
 102     addi  r4, r4, lo16((finish - .) + 4)
 103     ; restore LR
 104     mtlr  r0
 105     ; save address of finish as return-address for context-function
 106     ; will be entered after context-function returns
 107     std  r4, 168(r3)
 108
 109     ; restore return address from R6
 110     mtlr  r6
 111
 112     blr  ; return pointer to context-data
 113
 114 finish:
 115     ; save return address into R0
 116     mflr  r0
 117     ; save return address on stack, set up stack frame
 118     stw  r0, 8(r1)
 119     ; allocate stack space, R1  16 == 0
 120     stwu  r1, -32(r1)
 121
 122     ; set return value to zero
 123     li  r3, 0
 124     ; exit application
 125     bl  __exit
 126     nop