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authorAurelien Jarno <aurelien@aurel32.net>2016-08-02 09:18:59 +0200
committerAurelien Jarno <aurelien@aurel32.net>2016-08-02 09:18:59 +0200
commitb74d259fe793499134eb743222cd8dd7c74a31ce (patch)
treeec337eba9ce2431f6d9853b502d10423455c0378 /sysdeps/alpha
parentcb7f9d63b921ea1a1cbb4ab377a8484fd5da9a2b (diff)
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alpha: fix trunc for big input values
The alpha specific version of trunc and truncf always add and subtract 0x1.0p23 or 0x1.0p52 even for big values. This causes this kind of errors in the testsuite: Failure: Test: trunc_towardzero (0x1p107) Result: is: 1.6225927682921334e+32 0x1.fffffffffffffp+106 should be: 1.6225927682921336e+32 0x1.0000000000000p+107 difference: 1.8014398509481984e+16 0x1.0000000000000p+54 ulp : 0.5000 max.ulp : 0.0000 Change this by returning the input value when its absolute value is greater than 0x1.0p23 or 0x1.0p52. NaN have to go through the add and subtract operations to get possibly silenced. Finally remove the code to handle inexact exception, trunc should never generate such an exception. Changelog: * sysdeps/alpha/fpu/s_trunc.c (__trunc): Return the input value when its absolute value is greater than 0x1.0p52. [_IEEE_FP_INEXACT] Remove. * sysdeps/alpha/fpu/s_truncf.c (__truncf): Return the input value when its absolute value is greater than 0x1.0p23. [_IEEE_FP_INEXACT] Remove.
Diffstat (limited to 'sysdeps/alpha')
-rw-r--r--sysdeps/alpha/fpu/s_trunc.c7
-rw-r--r--sysdeps/alpha/fpu/s_truncf.c7
2 files changed, 6 insertions, 8 deletions
diff --git a/sysdeps/alpha/fpu/s_trunc.c b/sysdeps/alpha/fpu/s_trunc.c
index 16cb114..4b986a6 100644
--- a/sysdeps/alpha/fpu/s_trunc.c
+++ b/sysdeps/alpha/fpu/s_trunc.c
@@ -28,12 +28,11 @@ __trunc (double x)
double two52 = copysign (0x1.0p52, x);
double r, tmp;
+ if (isgreaterequal (fabs (x), 0x1.0p52))
+ return x;
+
__asm (
-#ifdef _IEEE_FP_INEXACT
- "addt/suic %2, %3, %1\n\tsubt/suic %1, %3, %0"
-#else
"addt/suc %2, %3, %1\n\tsubt/suc %1, %3, %0"
-#endif
: "=&f"(r), "=&f"(tmp)
: "f"(x), "f"(two52));
diff --git a/sysdeps/alpha/fpu/s_truncf.c b/sysdeps/alpha/fpu/s_truncf.c
index 2290f28..3e93356 100644
--- a/sysdeps/alpha/fpu/s_truncf.c
+++ b/sysdeps/alpha/fpu/s_truncf.c
@@ -27,12 +27,11 @@ __truncf (float x)
float two23 = copysignf (0x1.0p23, x);
float r, tmp;
+ if (isgreaterequal (fabsf (x), 0x1.0p23))
+ return x;
+
__asm (
-#ifdef _IEEE_FP_INEXACT
- "adds/suic %2, %3, %1\n\tsubs/suic %1, %3, %0"
-#else
"adds/suc %2, %3, %1\n\tsubs/suc %1, %3, %0"
-#endif
: "=&f"(r), "=&f"(tmp)
: "f"(x), "f"(two23));