From fa080de7afc95aa1c19a6e6fc0e0708ced2eadc4 Mon Sep 17 00:00:00 2001 From: Joseph Hunkeler Date: Wed, 8 Jul 2015 20:46:52 -0400 Subject: Initial commit --- unix/as.i386/zsvjmp.s | 45 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 45 insertions(+) create mode 100644 unix/as.i386/zsvjmp.s (limited to 'unix/as.i386/zsvjmp.s') diff --git a/unix/as.i386/zsvjmp.s b/unix/as.i386/zsvjmp.s new file mode 100644 index 00000000..cdec4cf5 --- /dev/null +++ b/unix/as.i386/zsvjmp.s @@ -0,0 +1,45 @@ + .file "zsvjmp.s" + +/# ZSVJMP, ZDOJMP -- Set up a jump (non-local goto) by saving the processor +/# registers in the buffer jmpbuf. A subsequent call to ZDOJMP restores +/# the registers, effecting a call in the context of the procedure which +/# originally called ZSVJMP, but with the new status code. These are Fortran +/# callable procedures. +/# +/# zsvjmp (jmp_buf, status) # (returns status) +/# zdojmp (jmp_buf, status) # (passes status to zsvjmp) +/# +/# These routines are directly comparable to the UNIX setjmp/longjmp, except +/# that they are Fortran callable kernel routines, i.e., trailing underscore, +/# call by reference, and no function returns. ZSVJMP requires an assembler +/# jacket routine to avoid modifying the call stack, but relies upon setjmp +/# to do the real work. ZDOJMP is implemented as a portable C routine in OS, +/# calling longjmp to do the restore. In these routines, JMP_BUF consists +/# of one longword containing the address of the STATUS variable, followed +/# by the "jmp_buf" used by setjmp/longjmp. +/# +/# This file contains the SUN/UNIX 386i (80386) version of ZSVJMP. + + .globl zsvjmp_ + + /# The following has nothing to do with ZSVJMP, and is included here + /# only because this assembler module is loaded with every process. + /# This code sets the value of the symbol MEM (the VOS or Fortran Mem + /# common) to zero, setting the origin for IRAF pointers to zero + /# rather than some arbitrary value, and ensuring that the MEM common + /# is aligned for all datatypes as well as page aligned. A further + /# advantage is that references to NULL pointers are likely to cause a + /# memory violation. + + .globl mem_ + mem_ = 0 + + .text +zsvjmp_: + movl 4(%esp), %ecx /# &jmpbuf to ECX + movl 8(%esp), %eax /# &status to EAX + movl %eax, (%ecx) /# store &status in jmpbuf[0] + clrl (%eax) /# zero the value of status + addl $4, %ecx /# change stack to point to &jmpbuf[1] + movl %ecx, 4(%esp) /# ... + jmp setjmp /# let setjmp do the rest -- cgit