target-i386: fix helper_fxtract() wrt softfloat

[qemu.git] / target-i386 / op_helper.c

diff --git a/target-i386/op_helper.c b/target-i386/op_helper.c
index 943d217e6e27a5caf5f374faa55400b70c4b3534..4850c63699ecbd9b2b4973a23b619061e38bb90d 100644 (file)
--- 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)