Changeset e799e3a in mainline

Timestamp:

2005-12-06T12:44:50Z (19 years ago)

Author:

Josef Cejka <malyzelenyhnus@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

ebff5e8

Parents:

211bd8a5

Message:

Some softfloat functions added - not compilable yet.

Location:

softfloat

Files:

• Makefile (added)
• generic/softfloat.c (modified) (1 diff)
• include/softfloat.h (modified) (2 diffs)

softfloat/generic/softfloat.c

@@ -30 +30 @@
 #include<softfloat.h>
 
+
+float __addsf3(float a, float b)
+{
+        float32 fa, fb;
+        a.f=a;
+        b.f=b;
+        if (a.parts.sign!=b.parts.sign) return subFloat32(a,b).f;
+        return addFloat32(a,b).f;
+};
+
+float __subsf3(float a, float b)
+{
+        float32 fa, fb;
+        a.f=a;
+        b.f=b;
+        if (a.parts.sign!=b.parts.sign) return addFloat32(a,b).f;
+        return subFloat32(a,b).f;
+};
+
+float __negsf2(float a)
+{
+        float32 fa;
+        fa.f=a;
+        fa.parts.sign=!fa.parts.sign;
+        return fa.f;
+};
+
+double __negdf2(double a)
+{
+        float64 fa;
+        fa.f=a;
+        fa.parts.sign=!fa.parts.sign;
+        return fa.f;
+};
+
+float32 addFloat32(float32 a, float32 b)
+{
+        __u32 expdiff;
+        __u32 exp1,exp2,mant1,mant2;
+        
+        expdiff=a.parts.exp - b.parts.exp;
+        if (expdiff<0) {
+                if (isFloat32NaN(a)) {
+                        //TODO: fix it
+                        return a;
+                };
+
+                mant1=b.parts.mantisa;
+                exp1=b.parts.exp;
+                mant2=a.parts.mantisa;
+                exp2=a.parts.exp;
+                expdiff*=-1;
+        } else {
+                if (isFloat32NaN(b)) {
+                        //TODO: fix it
+                        return b;
+                };
+                mant1=a.parts.mantisa;
+                exp1=a.parts.exp;
+                mant2=b.parts.mantisa;
+                exp2=b.parts.exp;
+        };
+
+        // create some space for rounding
+        mant1<<=6;
+        mant2<<=6;
+        
+        if (exp1!=0) {
+                mant1|=0x20000000; //add hidden bit
+        };
+        
+        if (exp2==0) {
+                --expdiff;      
+        } else {
+                mant2|=0x20000000; //hidden bit
+        };
+        
+        
+        if (expdiff>24) {
+                goto done; 
+        };
+        
+        mant2>>=expdiff;
+        mant1+=mant2;
+done:
+        //TODO: round mant1
+        a.parts.exp=exp1;
+        a.parts.mantisa=mant1>>6;
+        return a;
+};
+
+float32 subFloat32(float32 a, float32 b)
+{
+        
+        
+};
+
+inline int isFloat32NaN(float32 f)
+{       /* NaN : exp = 0xff and nonzero mantisa */
+        float32 fa;
+        fa.f=f;
+        return ((fa.parts.exp==0xFF)&&(fa.parts.mantisa));
+};
+
+inline int isFloat32SigNaN(float32 f)
+{       /* SigNaN : exp = 0xff mantisa = 1xxxxx..x (binary), where at least one x is nonzero */
+        float32 fa;
+        fa.f=f;
+        return ((fa.parts.exp==0xFF)&&(fa.parts.mantisa>0x400000));
+};
+

softfloat/include/softfloat.h

@@ -42 +42 @@
                 __u32 mantisa:23;
                 __u8 exp:8;
-                __u8    sign:1;
+                __u8 sign:1;
                 #else 
                 #endif
@@ -59 +59 @@
                 __u32 mantisa:52;
                 __u8 exp:11;
-                __u8    sign:1;
+                __u8 sign:1;
                 #else 
                 #endif
                 } parts __attribute__ ((packed));
         } float64_t;
+
+#define FLOAT32_MAX 0x7f800000
+#define FLOAT32_MIN 0xff800000
+#define FLOAT64_MAX
+#define FLOAT64_MIN
+
+#define FLOAT32_BIAS 0xF7
+#define FLOAT64_BIAS 0x3FF
+#define FLOAT80_BIAS 0x3FFF
+