do not preserve caller-saved registers

This commit is contained in:
Niko Matsakis 2011-10-12 16:43:40 -07:00 committed by Brian Anderson
parent 6a0d86c754
commit d3e865438f

View File

@ -20,19 +20,19 @@ The registers_t variable is in (%esp)
swap_registers:
// save the old context
movl 4(%esp), %eax
//movl %eax, 0(%eax)
movl %ebx, 4(%eax)
movl %ecx, 8(%eax)
movl %edx, 12(%eax)
movl %ebp, 16(%eax)
movl %esi, 20(%eax)
movl %edi, 24(%eax)
//movl %cs, 32(%eax)
//movl %ds, 34(%eax)
//movl %ss, 36(%eax)
//movl %es, 38(%eax)
//movl %fs, 40(%eax)
//movl %gs, 42(%eax)
//movl %eax, 0(%eax)
movl %ebx, 4(%eax)
//movl %ecx, 8(%eax)
//movl %edx, 12(%eax)
movl %ebp, 16(%eax)
movl %esi, 20(%eax)
movl %edi, 24(%eax)
//movl %cs, 32(%eax)
//movl %ds, 34(%eax)
//movl %ss, 36(%eax)
//movl %es, 38(%eax)
//movl %fs, 40(%eax)
//movl %gs, 42(%eax)
// save the flags
pushf
@ -48,20 +48,20 @@ swap_registers:
// restore the new context
movl 4(%esp), %eax
movl 4(%eax), %ebx
// save ecx for later...
movl 12(%eax), %edx
movl 16(%eax), %ebp
movl 20(%eax), %esi
movl 24(%eax), %edi
movl 28(%eax), %esp
// We can't actually change this...
//movl 32(%eax), %cs
//movl 34(%eax), %ds
//movl 36(%eax), %ss
//movl 38(%eax), %es
//movl 40(%eax), %fs
//movl 42(%eax), %gs
movl 4(%eax), %ebx
// save ecx for later...
//movl 12(%eax), %edx
movl 16(%eax), %ebp
movl 20(%eax), %esi
movl 24(%eax), %edi
movl 28(%eax), %esp
// We can't actually change this...
//movl 32(%eax), %cs
//movl 34(%eax), %ds
//movl 36(%eax), %ss
//movl 38(%eax), %es
//movl 40(%eax), %fs
//movl 42(%eax), %gs
// restore the flags
movl 44(%eax), %ecx
@ -69,8 +69,8 @@ swap_registers:
popf
// ok, now we can restore ecx
movl 8(%eax), %ecx
//movl 8(%eax), %ecx
// Return!
jmp *48(%eax)