mirror of
https://github.com/openhwgroup/cvw
synced 2025-02-11 06:05:49 +00:00
101 lines
2.8 KiB
C
101 lines
2.8 KiB
C
// softfloat_demo3.c
|
|
// james.stine@okstate.edu 15 August 2023
|
|
//
|
|
// Demonstrate using SoftFloat do compute a floating-point for quad, then print results
|
|
|
|
#include <stdio.h>
|
|
#include <stdint.h>
|
|
#include <inttypes.h>
|
|
#include <quadmath.h> // GCC Quad-Math Library
|
|
#include "softfloat.h"
|
|
#include "softfloat_types.h"
|
|
typedef union sp {
|
|
uint32_t v;
|
|
float f;
|
|
} sp;
|
|
|
|
typedef union dp {
|
|
uint64_t v;
|
|
double d;
|
|
} dp;
|
|
|
|
typedef union qp {
|
|
uint64_t v[2];
|
|
__float128 q;
|
|
} qp;
|
|
|
|
|
|
void printF32 (char *msg, float32_t f) {
|
|
sp conv;
|
|
int i, j;
|
|
conv.v = f.v; // use union to convert between hexadecimal and floating-point views
|
|
printf("%s: ", msg); // print out nicely
|
|
printf("0x%04x_%04x = %g\n", (conv.v >> 16),(conv.v & 0xFFFF), conv.f);
|
|
}
|
|
|
|
void printF64 (char *msg, float64_t d) {
|
|
dp conv;
|
|
int i, j;
|
|
conv.v = d.v; // use union to convert between hexadecimal and floating-point views
|
|
printf("%s: ", msg); // print out nicely
|
|
printf("0x%08lx_%08lx = %g\n", (conv.v >> 32),(conv.v & 0xFFFFFFFF), conv.d);
|
|
}
|
|
|
|
void printF128 (char *msg, float128_t q) {
|
|
qp conv;
|
|
int i, j;
|
|
char buf[64];
|
|
conv.v[0] = q.v[0]; // use union to convert between hexadecimal and floating-point views
|
|
conv.v[1] = q.v[1]; // use union to convert between hexadecimal and floating-point views
|
|
printf("%s: ", msg); // print out nicely
|
|
|
|
// Some compilers can understand %Q for printf on quad precision instead of the
|
|
// API call of quadmath_snprintf
|
|
// printf("0x%016" PRIx64 "_%016" PRIx64 " = %1.15Qe\n", q.v[1], q.v[0], conv.q);
|
|
quadmath_snprintf (buf, sizeof buf, "%1.15Qe", conv.q);
|
|
printf("0x%016" PRIx64 "_%016" PRIx64 " = %s\n", q.v[1], q.v[0], buf);
|
|
|
|
}
|
|
|
|
void printFlags(void) {
|
|
int NX = softfloat_exceptionFlags % 2;
|
|
int UF = (softfloat_exceptionFlags >> 1) % 2;
|
|
int OF = (softfloat_exceptionFlags >> 2) % 2;
|
|
int DZ = (softfloat_exceptionFlags >> 3) % 2;
|
|
int NV = (softfloat_exceptionFlags >> 4) % 2;
|
|
printf ("Flags: Inexact %d Underflow %d Overflow %d DivideZero %d Invalid %d\n",
|
|
NX, UF, OF, DZ, NV);
|
|
}
|
|
|
|
void softfloatInit(void) {
|
|
// rounding modes: RNE: softfloat_round_near_even
|
|
// RZ: softfloat_round_minMag
|
|
// RP: softfloat_round_max
|
|
// RM: softfloat_round_min
|
|
softfloat_roundingMode = softfloat_round_near_even;
|
|
softfloat_exceptionFlags = 0; // clear exceptions
|
|
softfloat_detectTininess = softfloat_tininess_afterRounding; // RISC-V behavior for tininess
|
|
}
|
|
|
|
int main() {
|
|
|
|
float128_t x, y, z;
|
|
float128_t r;
|
|
uint32_t u, v, w;
|
|
int32_t a, b, c;
|
|
|
|
x.v[1] = 0xBFFF988ECE97DFEB;
|
|
x.v[0] = 0xC3BBA082445B4836;
|
|
y.v[1] = 0x3F8EFFFFFFFFFFFF;
|
|
y.v[0] = 0xFFFFFFFFFFFFFFFF;
|
|
z.v[1] = 0x4001000000000000;
|
|
z.v[0] = 0x0000000000000000;
|
|
|
|
softfloatInit();
|
|
printF128("X", x); printF128("Y", y); printF128("Z", z);
|
|
r = f128_mulAdd(x, y, z);
|
|
printf("\n");
|
|
printF128("r", r);
|
|
|
|
}
|