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-rw-r--r--sysdeps/x86_64/fpu/e_expl.S19
1 files changed, 18 insertions, 1 deletions
diff --git a/sysdeps/x86_64/fpu/e_expl.S b/sysdeps/x86_64/fpu/e_expl.S
index c2d1d40ba5..d497b28973 100644
--- a/sysdeps/x86_64/fpu/e_expl.S
+++ b/sysdeps/x86_64/fpu/e_expl.S
@@ -35,6 +35,10 @@ c0: .byte 0, 0, 0, 0, 0, 0, 0xaa, 0xb8, 0xff, 0x3f
c1: .byte 0x20, 0xfa, 0xee, 0xc2, 0x5f, 0x70, 0xa5, 0xec, 0xed, 0x3f
.byte 0, 0, 0, 0, 0, 0
ASM_SIZE_DIRECTIVE(c1)
+ ASM_TYPE_DIRECTIVE(csat,@object)
+csat: .byte 0, 0, 0, 0, 0, 0, 0, 0x80, 0x0e, 0x40
+ .byte 0, 0, 0, 0, 0, 0
+ ASM_SIZE_DIRECTIVE(csat)
#ifdef PIC
# define MO(op) op##(%rip)
@@ -50,12 +54,25 @@ ENTRY(__ieee754_expl)
For the i686 the code can be written better.
-- drepper@cygnus.com. */
fxam /* Is NaN or +-Inf? */
+ movzwl 8+8(%rsp), %eax
+ andl $0x7fff, %eax
+ cmpl $0x400d, %eax
+ jle 3f
+ /* Overflow, underflow or infinity or NaN as argument. */
fstsw %ax
movb $0x45, %dh
andb %ah, %dh
cmpb $0x05, %dh
je 1f /* Is +-Inf, jump. */
- fldl2e /* 1 log2(e) */
+ cmpb $0x01, %dh
+ je 2f /* Is +-NaN, jump. */
+ /* Overflow or underflow; saturate. */
+ fstp %st
+ fldt MO(csat)
+ andb $2, %ah
+ jz 3f
+ fchs
+3: fldl2e /* 1 log2(e) */
fmul %st(1), %st /* 1 x log2(e) */
frndint /* 1 i */
fld %st(1) /* 2 x */