[sim] added SoftFloat-3 source

[riscv-isa-sim.git] / softfloat / SoftFloat-3 / source / f64_rem.c

diff --git a/softfloat/SoftFloat-3/source/f64_rem.c b/softfloat/SoftFloat-3/source/f64_rem.c
new file mode 100755 (executable)
index 0000000..08fcd78
--- /dev/null
+++ b/softfloat/SoftFloat-3/source/f64_rem.c
@@ -0,0 +1,113 @@
+
+#include <stdbool.h>
+#include <stdint.h>
+#include "platform.h"
+#include "primitives.h"
+#include "internals.h"
+#include "specialize.h"
+#include "softfloat.h"
+
+float64_t f64_rem( float64_t a, float64_t b )
+{
+    union ui64_f64 uA;
+    uint_fast64_t uiA;
+    bool signA;
+    int_fast16_t expA;
+    uint_fast64_t sigA;
+    union ui64_f64 uB;
+    uint_fast64_t uiB;
+    bool signB;
+    int_fast16_t expB;
+    uint_fast64_t sigB;
+    struct exp16_sig64 normExpSig;
+    int_fast16_t expDiff;
+    uint_fast64_t q, alternateSigA;
+    uint64_t sigMean;
+    bool signZ;
+    uint_fast64_t uiZ;
+    union ui64_f64 uZ;
+
+    uA.f = a;
+    uiA = uA.ui;
+    signA = signF64UI( uiA );
+    expA = expF64UI( uiA );
+    sigA = fracF64UI( uiA );
+    uB.f = b;
+    uiB = uB.ui;
+    signB = signF64UI( uiB );
+    expB = expF64UI( uiB );
+    sigB = fracF64UI( uiB );
+    if ( expA == 0x7FF ) {
+        if ( sigA || ( ( expB == 0x7FF ) && sigB ) ) goto propagateNaN;
+        goto invalid;
+    }
+    if ( expB == 0x7FF ) {
+        if ( sigB ) goto propagateNaN;
+        return a;
+    }
+    if ( ! expB ) {
+        if ( ! sigB ) goto invalid;
+        normExpSig = softfloat_normSubnormalF64Sig( sigB );
+        expB = normExpSig.exp;
+        sigB = normExpSig.sig;
+    }
+    if ( ! expA ) {
+        if ( ! sigA ) return a;
+        normExpSig = softfloat_normSubnormalF64Sig( sigA );
+        expA = normExpSig.exp;
+        sigA = normExpSig.sig;
+    }
+    expDiff = expA - expB;
+    sigA = ( sigA | UINT64_C( 0x0010000000000000 ) )<<11;
+    sigB = ( sigB | UINT64_C( 0x0010000000000000 ) )<<11;
+    if ( expDiff < 0 ) {
+        if ( expDiff < -1 ) return a;
+        sigA >>= 1;
+    }
+    q = ( sigB <= sigA );
+    if ( q ) sigA -= sigB;
+    expDiff -= 64;
+    while ( 0 < expDiff ) {
+        q = softfloat_estimateDiv128To64( sigA, 0, sigB );
+        q = ( 2 < q ) ? q - 2 : 0;
+        sigA = - ( ( sigB>>2 ) * q );
+        expDiff -= 62;
+    }
+    expDiff += 64;
+    if ( 0 < expDiff ) {
+        q = softfloat_estimateDiv128To64( sigA, 0, sigB );
+        q = ( 2 < q ) ? q - 2 : 0;
+        q >>= 64 - expDiff;
+        sigB >>= 2;
+        sigA = ( ( sigA>>1 )<<( expDiff - 1 ) ) - sigB * q;
+    } else {
+        sigA >>= 2;
+        sigB >>= 2;
+    }
+    do {
+        alternateSigA = sigA;
+        ++q;
+        sigA -= sigB;
+    } while ( sigA < UINT64_C( 0x8000000000000000 ) );
+    sigMean = sigA + alternateSigA;
+    if (
+        ( UINT64_C( 0x8000000000000000 ) <= sigMean )
+            || ( ! sigMean && ( q & 1 ) )
+    ) {
+        sigA = alternateSigA;
+    }
+    signZ = ( UINT64_C( 0x8000000000000000 ) <= sigA );
+    if ( signZ ) sigA = - sigA;
+    return softfloat_normRoundPackToF64( signA ^ signZ, expB, sigA );
+ propagateNaN:
+    uiZ = softfloat_propagateNaNF64UI( uiA, uiB );
+    goto uiZ;
+ invalid:
+    softfloat_raiseFlags( softfloat_flag_invalid );
+    uiZ = defaultNaNF64UI;
+ uiZ:
+    uZ.ui = uiZ;
+    return uZ.f;
+
+}
+