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-rw-r--r--src/pkg/runtime/float.c171
1 files changed, 4 insertions, 167 deletions
diff --git a/src/pkg/runtime/float.c b/src/pkg/runtime/float.c
index f481519f6..42082e434 100644
--- a/src/pkg/runtime/float.c
+++ b/src/pkg/runtime/float.c
@@ -4,170 +4,7 @@
#include "runtime.h"
-static uint64 uvnan = 0x7FF0000000000001ULL;
-static uint64 uvinf = 0x7FF0000000000000ULL;
-static uint64 uvneginf = 0xFFF0000000000000ULL;
-
-uint32
-runtime·float32tobits(float32 f)
-{
- // The obvious cast-and-pointer code is technically
- // not valid, and gcc miscompiles it. Use a union instead.
- union {
- float32 f;
- uint32 i;
- } u;
- u.f = f;
- return u.i;
-}
-
-uint64
-runtime·float64tobits(float64 f)
-{
- // The obvious cast-and-pointer code is technically
- // not valid, and gcc miscompiles it. Use a union instead.
- union {
- float64 f;
- uint64 i;
- } u;
- u.f = f;
- return u.i;
-}
-
-float64
-runtime·float64frombits(uint64 i)
-{
- // The obvious cast-and-pointer code is technically
- // not valid, and gcc miscompiles it. Use a union instead.
- union {
- float64 f;
- uint64 i;
- } u;
- u.i = i;
- return u.f;
-}
-
-float32
-runtime·float32frombits(uint32 i)
-{
- // The obvious cast-and-pointer code is technically
- // not valid, and gcc miscompiles it. Use a union instead.
- union {
- float32 f;
- uint32 i;
- } u;
- u.i = i;
- return u.f;
-}
-
-bool
-runtime·isInf(float64 f, int32 sign)
-{
- uint64 x;
-
- x = runtime·float64tobits(f);
- if(sign == 0)
- return x == uvinf || x == uvneginf;
- if(sign > 0)
- return x == uvinf;
- return x == uvneginf;
-}
-
-float64
-runtime·NaN(void)
-{
- return runtime·float64frombits(uvnan);
-}
-
-bool
-runtime·isNaN(float64 f)
-{
- uint64 x;
-
- x = runtime·float64tobits(f);
- return ((uint32)(x>>52) & 0x7FF) == 0x7FF && !runtime·isInf(f, 0);
-}
-
-float64
-runtime·Inf(int32 sign)
-{
- if(sign >= 0)
- return runtime·float64frombits(uvinf);
- else
- return runtime·float64frombits(uvneginf);
-}
-
-enum
-{
- MASK = 0x7ffL,
- SHIFT = 64-11-1,
- BIAS = 1022L,
-};
-
-float64
-runtime·frexp(float64 d, int32 *ep)
-{
- uint64 x;
-
- if(d == 0) {
- *ep = 0;
- return 0;
- }
- x = runtime·float64tobits(d);
- *ep = (int32)((x >> SHIFT) & MASK) - BIAS;
- x &= ~((uint64)MASK << SHIFT);
- x |= (uint64)BIAS << SHIFT;
- return runtime·float64frombits(x);
-}
-
-float64
-runtime·ldexp(float64 d, int32 e)
-{
- uint64 x;
-
- if(d == 0)
- return 0;
- x = runtime·float64tobits(d);
- e += (int32)(x >> SHIFT) & MASK;
- if(e <= 0)
- return 0; /* underflow */
- if(e >= MASK){ /* overflow */
- if(d < 0)
- return runtime·Inf(-1);
- return runtime·Inf(1);
- }
- x &= ~((uint64)MASK << SHIFT);
- x |= (uint64)e << SHIFT;
- return runtime·float64frombits(x);
-}
-
-float64
-runtime·modf(float64 d, float64 *ip)
-{
- float64 dd;
- uint64 x;
- int32 e;
-
- if(d < 1) {
- if(d < 0) {
- d = runtime·modf(-d, ip);
- *ip = -*ip;
- return -d;
- }
- *ip = 0;
- return d;
- }
-
- x = runtime·float64tobits(d);
- e = (int32)((x >> SHIFT) & MASK) - BIAS;
-
- /*
- * Keep the top 11+e bits; clear the rest.
- */
- if(e <= 64-11)
- x &= ~(((uint64)1 << (64LL-11LL-e))-1);
- dd = runtime·float64frombits(x);
- *ip = dd;
- return d - dd;
-}
-
+// used as float64 via runtime· names
+uint64 ·nan = 0x7FF8000000000001ULL;
+uint64 ·posinf = 0x7FF0000000000000ULL;
+uint64 ·neginf = 0xFFF0000000000000ULL;