diff options
Diffstat (limited to 'src/fenv/i386/fenv.s')
| -rw-r--r-- | src/fenv/i386/fenv.s | 39 |
1 files changed, 27 insertions, 12 deletions
diff --git a/src/fenv/i386/fenv.s b/src/fenv/i386/fenv.s index 9bba40a5..a8540add 100644 --- a/src/fenv/i386/fenv.s +++ b/src/fenv/i386/fenv.s @@ -4,26 +4,41 @@ .type feclearexcept,@function feclearexcept: mov 4(%esp),%ecx - not %ecx + fnstsw %ax # consider sse fenv as well if the cpu has XMM capability call 1f 1: addl $__hwcap-1b,(%esp) pop %edx testl $0x02000000,(%edx) + jz 2f + # maintain exceptions in the sse mxcsr, clear x87 exceptions + test %eax,%ecx jz 1f - stmxcsr 4(%esp) - and %ecx,4(%esp) - ldmxcsr 4(%esp) -1: test $0x3f,%ecx - jnz 2f -1: fnclex - xor %eax,%eax + fnclex +1: push %edx + stmxcsr (%esp) + pop %edx + and $0x3f,%eax + or %eax,%edx + test %edx,%ecx + jz 1f + not %ecx + and %ecx,%edx + push %edx + ldmxcsr (%esp) + pop %edx +1: xor %eax,%eax ret -2: fnstsw %ax - # TODO: only load/store fenv if exceptions arent clear yet - and %ecx,%eax + # only do the expensive x87 fenv load/store when needed +2: test %eax,%ecx jz 1b - sub $32,%esp + not %ecx + and %ecx,%eax + test $0x3f,%eax + jz 1f + fnclex + jmp 1b +1: sub $32,%esp fnstenv (%esp) mov %al,4(%esp) fldenv (%esp) |