From c9ad19c57b4e35dda507ec636443069048a4ad72 Mon Sep 17 00:00:00 2001 From: Aurelien Jarno Date: Wed, 20 Apr 2011 13:04:23 +0200 Subject: [PATCH] target-i386: fix helper_fxtract() wrt softfloat With softfloat it's not possible to play with the overflow of an unsigned value to get the 0 case partially correct. Use a special case for that. Using a division to generate an infinity is the easiest way that works for both softfloat and softfloat-native. Reviewed-by: Peter Maydell Signed-off-by: Aurelien Jarno --- target-i386/op_helper.c | 23 ++++++++++++++++------- 1 file changed, 16 insertions(+), 7 deletions(-) diff --git a/target-i386/op_helper.c b/target-i386/op_helper.c index 943d217e6e..4850c63699 100644 --- a/target-i386/op_helper.c +++ b/target-i386/op_helper.c @@ -4005,15 +4005,24 @@ void helper_fpatan(void) void helper_fxtract(void) { CPU86_LDoubleU temp; - unsigned int expdif; temp.d = ST0; - expdif = EXPD(temp) - EXPBIAS; - /*DP exponent bias*/ - ST0 = expdif; - fpush(); - BIASEXPONENT(temp); - ST0 = temp.d; + + if (floatx_is_zero(ST0)) { + /* Easy way to generate -inf and raising division by 0 exception */ + ST0 = floatx_div(floatx_chs(floatx_one), floatx_zero, &env->fp_status); + fpush(); + ST0 = temp.d; + } else { + int expdif; + + expdif = EXPD(temp) - EXPBIAS; + /*DP exponent bias*/ + ST0 = int32_to_floatx(expdif, &env->fp_status); + fpush(); + BIASEXPONENT(temp); + ST0 = temp.d; + } } void helper_fprem1(void) -- 2.11.4.GIT