libc-top-half/musl/src/fenv/i386/fenv.s

   1 .hidden __hwcap
   2
   3 .global feclearexcept
   4 .type feclearexcept,@function
   5 feclearexcept:
   6         mov 4(%esp),%ecx
   7         and $0x3f,%ecx
   8         fnstsw %ax
   9                 # consider sse fenv as well if the cpu has XMM capability
  10         call 1f
  11 1:      addl $__hwcap-1b,(%esp)
  12         pop %edx
  13         testl $0x02000000,(%edx)
  14         jz 2f
  15                 # maintain exceptions in the sse mxcsr, clear x87 exceptions
  16         test %eax,%ecx
  17         jz 1f
  18         fnclex
  19 1:      push %edx
  20         stmxcsr (%esp)
  21         pop %edx
  22         and $0x3f,%eax
  23         or %eax,%edx
  24         test %edx,%ecx
  25         jz 1f
  26         not %ecx
  27         and %ecx,%edx
  28         push %edx
  29         ldmxcsr (%esp)
  30         pop %edx
  31 1:      xor %eax,%eax
  32         ret
  33                 # only do the expensive x87 fenv load/store when needed
  34 2:      test %eax,%ecx
  35         jz 1b
  36         not %ecx
  37         and %ecx,%eax
  38         test $0x3f,%eax
  39         jz 1f
  40         fnclex
  41         jmp 1b
  42 1:      sub $32,%esp
  43         fnstenv (%esp)
  44         mov %al,4(%esp)
  45         fldenv (%esp)
  46         add $32,%esp
  47         xor %eax,%eax
  48         ret
  49
  50 .global feraiseexcept
  51 .type feraiseexcept,@function
  52 feraiseexcept:
  53         mov 4(%esp),%eax
  54         and $0x3f,%eax
  55         sub $32,%esp
  56         fnstenv (%esp)
  57         or %al,4(%esp)
  58         fldenv (%esp)
  59         add $32,%esp
  60         xor %eax,%eax
  61         ret
  62
  63 .global __fesetround
  64 .hidden __fesetround
  65 .type __fesetround,@function
  66 __fesetround:
  67         mov 4(%esp),%ecx
  68         push %eax
  69         xor %eax,%eax
  70         fnstcw (%esp)
  71         andb $0xf3,1(%esp)
  72         or %ch,1(%esp)
  73         fldcw (%esp)
  74                 # consider sse fenv as well if the cpu has XMM capability
  75         call 1f
  76 1:      addl $__hwcap-1b,(%esp)
  77         pop %edx
  78         testl $0x02000000,(%edx)
  79         jz 1f
  80         stmxcsr (%esp)
  81         shl $3,%ch
  82         andb $0x9f,1(%esp)
  83         or %ch,1(%esp)
  84         ldmxcsr (%esp)
  85 1:      pop %ecx
  86         ret
  87
  88 .global fegetround
  89 .type fegetround,@function
  90 fegetround:
  91         push %eax
  92         fnstcw (%esp)
  93         pop %eax
  94         and $0xc00,%eax
  95         ret
  96
  97 .global fegetenv
  98 .type fegetenv,@function
  99 fegetenv:
 100         mov 4(%esp),%ecx
 101         xor %eax,%eax
 102         fnstenv (%ecx)
 103                 # consider sse fenv as well if the cpu has XMM capability
 104         call 1f
 105 1:      addl $__hwcap-1b,(%esp)
 106         pop %edx
 107         testl $0x02000000,(%edx)
 108         jz 1f
 109         push %eax
 110         stmxcsr (%esp)
 111         pop %edx
 112         and $0x3f,%edx
 113         or %edx,4(%ecx)
 114 1:      ret
 115
 116 .global fesetenv
 117 .type fesetenv,@function
 118 fesetenv:
 119         mov 4(%esp),%ecx
 120         xor %eax,%eax
 121         inc %ecx
 122         jz 1f
 123         fldenv -1(%ecx)
 124         movl -1(%ecx),%ecx
 125         jmp 2f
 126 1:      push %eax
 127         push %eax
 128         push %eax
 129         push %eax
 130         pushl $0xffff
 131         push %eax
 132         pushl $0x37f
 133         fldenv (%esp)
 134         add $28,%esp
 135                 # consider sse fenv as well if the cpu has XMM capability
 136 2:      call 1f
 137 1:      addl $__hwcap-1b,(%esp)
 138         pop %edx
 139         testl $0x02000000,(%edx)
 140         jz 1f
 141                 # mxcsr := same rounding mode, cleared exceptions, default mask
 142         and $0xc00,%ecx
 143         shl $3,%ecx
 144         or $0x1f80,%ecx
 145         mov %ecx,4(%esp)
 146         ldmxcsr 4(%esp)
 147 1:      ret
 148
 149 .global fetestexcept
 150 .type fetestexcept,@function
 151 fetestexcept:
 152         mov 4(%esp),%ecx
 153         and $0x3f,%ecx
 154         fnstsw %ax
 155                 # consider sse fenv as well if the cpu has XMM capability
 156         call 1f
 157 1:      addl $__hwcap-1b,(%esp)
 158         pop %edx
 159         testl $0x02000000,(%edx)
 160         jz 1f
 161         stmxcsr 4(%esp)
 162         or 4(%esp),%eax
 163 1:      and %ecx,%eax
 164         ret