tests/tcg/i386/test-i386-fprem.c - qemu - Git at Google

 /*
  *  x86 FPREM test - executes the FPREM and FPREM1 instructions with corner case
  *  operands and prints the operands, result and FPU status word.
  *
  *  Run this on real hardware, then under QEMU, and diff the outputs, to compare
  *  QEMU's implementation to your hardware. The 'run-test-i386-fprem' make
  *  target does this.
  *
  *  Copyright (c) 2003 Fabrice Bellard
  *  Copyright (c) 2012 Catalin Patulea
  *
  *  This program is free software; you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License as published by
  *  the Free Software Foundation; either version 2 of the License, or
  *  (at your option) any later version.
  *
  *  This program is distributed in the hope that it will be useful,
  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  *  GNU General Public License for more details.
  *
  *  You should have received a copy of the GNU General Public License
  *  along with this program; if not, see <http://www.gnu.org/licenses/>.
  */

 #include <stdio.h>
 #include <stdint.h>

 #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))

 /*
  * Inspired by <ieee754.h>'s union ieee854_long_double, but with single
  * long long mantissa fields and assuming little-endianness for simplicity.
  */
 union float80u {
     long double d;

     /* This is the IEEE 854 double-extended-precision format.  */
     struct {
         unsigned long long mantissa:63;
         unsigned int one:1;
         unsigned int exponent:15;
         unsigned int negative:1;
         unsigned int empty:16;
     } __attribute__((packed)) ieee;

     /* This is for NaNs in the IEEE 854 double-extended-precision format.  */
     struct {
         unsigned long long mantissa:62;
         unsigned int quiet_nan:1;
         unsigned int one:1;
         unsigned int exponent:15;
         unsigned int negative:1;
         unsigned int empty:16;
     } __attribute__((packed)) ieee_nan;
 };

 #define IEEE854_LONG_DOUBLE_BIAS 0x3fff

 static const union float80u q_nan = {
     .ieee_nan.negative = 0,  /* X */
     .ieee_nan.exponent = 0x7fff,
     .ieee_nan.one = 1,
     .ieee_nan.quiet_nan = 1,
     .ieee_nan.mantissa = 0,
 };

 static const union float80u s_nan = {
     .ieee_nan.negative = 0,  /* X */
     .ieee_nan.exponent = 0x7fff,
     .ieee_nan.one = 1,
     .ieee_nan.quiet_nan = 0,
     .ieee_nan.mantissa = 1,  /* nonzero */
 };

 static const union float80u pos_inf = {
     .ieee.negative = 0,
     .ieee.exponent = 0x7fff,
     .ieee.one = 1,
     .ieee.mantissa = 0,
 };

 static const union float80u pseudo_pos_inf = {  /* "unsupported" */
     .ieee.negative = 0,
     .ieee.exponent = 0x7fff,
     .ieee.one = 0,
     .ieee.mantissa = 0,
 };

 static const union float80u pos_denorm = {
     .ieee.negative = 0,
     .ieee.exponent = 0,
     .ieee.one = 0,
     .ieee.mantissa = 1,
 };

 static const union float80u smallest_positive_norm = {
     .ieee.negative = 0,
     .ieee.exponent = 1,
     .ieee.one = 1,
     .ieee.mantissa = 0,
 };

 static void fninit()
 {
     asm volatile ("fninit\n");
 }

 static long double fprem(long double a, long double b, uint16_t *sw)
 {
     long double result;
     asm volatile ("fprem\n"
                   "fnstsw %1\n"
                   : "=t" (result), "=m" (*sw)
                   : "0" (a), "u" (b)
                   : "st(1)");
     return result;
 }

 static long double fprem1(long double a, long double b, uint16_t *sw)
 {
     long double result;
     asm volatile ("fprem1\n"
                   "fnstsw %1\n"
                   : "=t" (result), "=m" (*sw)
                   : "0" (a), "u" (b)
                   : "st(1)");
     return result;
 }

 #define FPUS_IE (1 << 0)
 #define FPUS_DE (1 << 1)
 #define FPUS_ZE (1 << 2)
 #define FPUS_OE (1 << 3)
 #define FPUS_UE (1 << 4)
 #define FPUS_PE (1 << 5)
 #define FPUS_SF (1 << 6)
 #define FPUS_SE (1 << 7)
 #define FPUS_C0 (1 << 8)
 #define FPUS_C1 (1 << 9)
 #define FPUS_C2 (1 << 10)
 #define FPUS_TOP 0x3800
 #define FPUS_C3 (1 << 14)
 #define FPUS_B  (1 << 15)

 #define FPUS_EMASK 0x007f

 #define FPUC_EM 0x3f

 static void psw(uint16_t sw)
 {
     printf("SW:  C3 TopC2C1C0\n");
     printf("SW: %c %d %3d %d %d %d %c %c %c %c %c %c %c %c\n",
            sw & FPUS_B ? 'B' : 'b',
            !!(sw & FPUS_C3),
            (sw & FPUS_TOP) >> 11,
            !!(sw & FPUS_C2),
            !!(sw & FPUS_C1),
            !!(sw & FPUS_C0),
            (sw & FPUS_SE) ? 'S' : 's',
            (sw & FPUS_SF) ? 'F' : 'f',
            (sw & FPUS_PE) ? 'P' : 'p',
            (sw & FPUS_UE) ? 'U' : 'u',
            (sw & FPUS_OE) ? 'O' : 'o',
            (sw & FPUS_ZE) ? 'Z' : 'z',
            (sw & FPUS_DE) ? 'D' : 'd',
            (sw & FPUS_IE) ? 'I' : 'i');
 }

 static void do_fprem(long double a, long double b)
 {
     const union float80u au = {.d = a};
     const union float80u bu = {.d = b};
     union float80u ru;
     uint16_t sw;

     printf("A: S=%d Exp=%04x Int=%d (QNaN=%d) Sig=%016llx (%.06Le)\n",
            au.ieee.negative, au.ieee.exponent, au.ieee.one,
            au.ieee_nan.quiet_nan, (unsigned long long)au.ieee.mantissa,
            a);
     printf("B: S=%d Exp=%04x Int=%d (QNaN=%d) Sig=%016llx (%.06Le)\n",
            bu.ieee.negative, bu.ieee.exponent, bu.ieee.one,
            bu.ieee_nan.quiet_nan, (unsigned long long)bu.ieee.mantissa,
            b);
     fflush(stdout);

     fninit();
     ru.d = fprem(a, b, &sw);
     psw(sw);

     printf("R : S=%d Exp=%04x Int=%d (QNaN=%d) Sig=%016llx (%.06Le)\n",
            ru.ieee.negative, ru.ieee.exponent, ru.ieee.one,
            ru.ieee_nan.quiet_nan, (unsigned long long)ru.ieee.mantissa,
            ru.d);

     fninit();
     ru.d = fprem1(a, b, &sw);
     psw(sw);

     printf("R1: S=%d Exp=%04x Int=%d (QNaN=%d) Sig=%016llx (%.06Le)\n",
            ru.ieee.negative, ru.ieee.exponent, ru.ieee.one,
            ru.ieee_nan.quiet_nan, (unsigned long long)ru.ieee.mantissa,
            ru.d);

     printf("\n");
 }

 static void do_fprem_stack_underflow(void)
 {
     const long double a = 1.0;
     union float80u ru;
     uint16_t sw;

     fninit();
     asm volatile ("fprem\n"
                   "fnstsw %1\n"
                   : "=t" (ru.d), "=m" (sw)
                   : "0" (a)
                   : "st(1)");
     psw(sw);

     printf("R: S=%d Exp=%04x Int=%d (QNaN=%d) Sig=%016llx (%.06Le)\n",
            ru.ieee.negative, ru.ieee.exponent, ru.ieee.one,
            ru.ieee_nan.quiet_nan, (unsigned long long)ru.ieee.mantissa,
            ru.d);
     printf("\n");
 }

 static void test_fprem_cases(void)
 {
     printf("= stack underflow =\n");
     do_fprem_stack_underflow();

     printf("= invalid operation =\n");
     do_fprem(q_nan.d, 1.0);
     do_fprem(s_nan.d, 1.0);
     do_fprem(1.0, 0.0);
     do_fprem(pos_inf.d, 1.0);
     do_fprem(pseudo_pos_inf.d, 1.0);

     printf("= denormal =\n");
     do_fprem(pos_denorm.d, 1.0);
     do_fprem(1.0, pos_denorm.d);

     do_fprem(smallest_positive_norm.d, smallest_positive_norm.d);

     /* printf("= underflow =\n"); */
     /* TODO: Is there a case where FPREM raises underflow? */
 }

 static void test_fprem_pairs(void)
 {
     unsigned long long count;

     unsigned int negative_index_a = 0;
     unsigned int negative_index_b = 0;
     static const unsigned int negative_values[] = {
         0,
         1,
     };

     unsigned int exponent_index_a = 0;
     unsigned int exponent_index_b = 0;
     static const unsigned int exponent_values[] = {
         0,
         1,
         2,
         IEEE854_LONG_DOUBLE_BIAS - 1,
         IEEE854_LONG_DOUBLE_BIAS,
         IEEE854_LONG_DOUBLE_BIAS + 1,
         0x7ffd,
         0x7ffe,
         0x7fff,
     };

     unsigned int one_index_a = 0;
     unsigned int one_index_b = 0;
     static const unsigned int one_values[] = {
         0,
         1,
     };

     unsigned int quiet_nan_index_a = 0;
     unsigned int quiet_nan_index_b = 0;
     static const unsigned int quiet_nan_values[] = {
         0,
         1,
     };

     unsigned int mantissa_index_a = 0;
     unsigned int mantissa_index_b = 0;
     static const unsigned long long mantissa_values[] = {
         0,
         1,
         2,
         0x3ffffffffffffffdULL,
         0x3ffffffffffffffeULL,
         0x3fffffffffffffffULL,
     };

     for (count = 0; ; ++count) {
 #define INIT_FIELD(var, field) \
             .ieee_nan.field = field##_values[field##_index_##var]
         const union float80u a = {
             INIT_FIELD(a, negative),
             INIT_FIELD(a, exponent),
             INIT_FIELD(a, one),
             INIT_FIELD(a, quiet_nan),
             INIT_FIELD(a, mantissa),
         };
         const union float80u b = {
             INIT_FIELD(b, negative),
             INIT_FIELD(b, exponent),
             INIT_FIELD(b, one),
             INIT_FIELD(b, quiet_nan),
             INIT_FIELD(b, mantissa),
         };
 #undef INIT_FIELD

         do_fprem(a.d, b.d);

         int carry = 1;
 #define CARRY_INTO(var, field) do { \
             if (carry) { \
                 if (++field##_index_##var == ARRAY_SIZE(field##_values)) { \
                     field##_index_##var = 0; \
                 } else { \
                     carry = 0; \
                 } \
             } \
         } while (0)
         CARRY_INTO(b, mantissa);
         CARRY_INTO(b, quiet_nan);
         CARRY_INTO(b, one);
         CARRY_INTO(b, exponent);
         CARRY_INTO(b, negative);
         CARRY_INTO(a, mantissa);
         CARRY_INTO(a, quiet_nan);
         CARRY_INTO(a, one);
         CARRY_INTO(a, exponent);
         CARRY_INTO(a, negative);
 #undef CARRY_INTO

         if (carry) {
             break;
         }
     }

     fprintf(stderr, "test-i386-fprem: tested %llu cases\n", count);
 }

 int main(int argc, char **argv)
 {
     test_fprem_cases();
     test_fprem_pairs();
     return 0;
 }
	/*
	* x86 FPREM test - executes the FPREM and FPREM1 instructions with corner case
	* operands and prints the operands, result and FPU status word.
	*
	* Run this on real hardware, then under QEMU, and diff the outputs, to compare
	* QEMU's implementation to your hardware. The 'run-test-i386-fprem' make
	* target does this.
	*
	* Copyright (c) 2003 Fabrice Bellard
	* Copyright (c) 2012 Catalin Patulea
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License as published by
	* the Free Software Foundation; either version 2 of the License, or
	* (at your option) any later version.
	*
	* This program is distributed in the hope that it will be useful,
	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	* GNU General Public License for more details.
	*
	* You should have received a copy of the GNU General Public License
	* along with this program; if not, see <http://www.gnu.org/licenses/>.
	*/

	#include <stdio.h>
	#include <stdint.h>

	#define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))

	/*
	* Inspired by <ieee754.h>'s union ieee854_long_double, but with single
	* long long mantissa fields and assuming little-endianness for simplicity.
	*/
	union float80u {
	long double d;

	/* This is the IEEE 854 double-extended-precision format. */
	struct {
	unsigned long long mantissa:63;
	unsigned int one:1;
	unsigned int exponent:15;
	unsigned int negative:1;
	unsigned int empty:16;
	} __attribute__((packed)) ieee;

	/* This is for NaNs in the IEEE 854 double-extended-precision format. */
	struct {
	unsigned long long mantissa:62;
	unsigned int quiet_nan:1;
	unsigned int one:1;
	unsigned int exponent:15;
	unsigned int negative:1;
	unsigned int empty:16;
	} __attribute__((packed)) ieee_nan;
	};

	#define IEEE854_LONG_DOUBLE_BIAS 0x3fff

	static const union float80u q_nan = {
	.ieee_nan.negative = 0, /* X */
	.ieee_nan.exponent = 0x7fff,
	.ieee_nan.one = 1,
	.ieee_nan.quiet_nan = 1,
	.ieee_nan.mantissa = 0,
	};

	static const union float80u s_nan = {
	.ieee_nan.negative = 0, /* X */
	.ieee_nan.exponent = 0x7fff,
	.ieee_nan.one = 1,
	.ieee_nan.quiet_nan = 0,
	.ieee_nan.mantissa = 1, /* nonzero */
	};

	static const union float80u pos_inf = {
	.ieee.negative = 0,
	.ieee.exponent = 0x7fff,
	.ieee.one = 1,
	.ieee.mantissa = 0,
	};

	static const union float80u pseudo_pos_inf = { /* "unsupported" */
	.ieee.negative = 0,
	.ieee.exponent = 0x7fff,
	.ieee.one = 0,
	.ieee.mantissa = 0,
	};

	static const union float80u pos_denorm = {
	.ieee.negative = 0,
	.ieee.exponent = 0,
	.ieee.one = 0,
	.ieee.mantissa = 1,
	};

	static const union float80u smallest_positive_norm = {
	.ieee.negative = 0,
	.ieee.exponent = 1,
	.ieee.one = 1,
	.ieee.mantissa = 0,
	};

	static void fninit()
	{
	asm volatile ("fninit\n");
	}

	static long double fprem(long double a, long double b, uint16_t *sw)
	{
	long double result;
	asm volatile ("fprem\n"
	"fnstsw %1\n"
	: "=t" (result), "=m" (*sw)
	: "0" (a), "u" (b)
	: "st(1)");
	return result;
	}

	static long double fprem1(long double a, long double b, uint16_t *sw)
	{
	long double result;
	asm volatile ("fprem1\n"
	"fnstsw %1\n"
	: "=t" (result), "=m" (*sw)
	: "0" (a), "u" (b)
	: "st(1)");
	return result;
	}

	#define FPUS_IE (1 << 0)
	#define FPUS_DE (1 << 1)
	#define FPUS_ZE (1 << 2)
	#define FPUS_OE (1 << 3)
	#define FPUS_UE (1 << 4)
	#define FPUS_PE (1 << 5)
	#define FPUS_SF (1 << 6)
	#define FPUS_SE (1 << 7)
	#define FPUS_C0 (1 << 8)
	#define FPUS_C1 (1 << 9)
	#define FPUS_C2 (1 << 10)
	#define FPUS_TOP 0x3800
	#define FPUS_C3 (1 << 14)
	#define FPUS_B (1 << 15)

	#define FPUS_EMASK 0x007f

	#define FPUC_EM 0x3f

	static void psw(uint16_t sw)
	{
	printf("SW: C3 TopC2C1C0\n");
	printf("SW: %c %d %3d %d %d %d %c %c %c %c %c %c %c %c\n",
	sw & FPUS_B ? 'B' : 'b',
	!!(sw & FPUS_C3),
	(sw & FPUS_TOP) >> 11,
	!!(sw & FPUS_C2),
	!!(sw & FPUS_C1),
	!!(sw & FPUS_C0),
	(sw & FPUS_SE) ? 'S' : 's',
	(sw & FPUS_SF) ? 'F' : 'f',
	(sw & FPUS_PE) ? 'P' : 'p',
	(sw & FPUS_UE) ? 'U' : 'u',
	(sw & FPUS_OE) ? 'O' : 'o',
	(sw & FPUS_ZE) ? 'Z' : 'z',
	(sw & FPUS_DE) ? 'D' : 'd',
	(sw & FPUS_IE) ? 'I' : 'i');
	}

	static void do_fprem(long double a, long double b)
	{
	const union float80u au = {.d = a};
	const union float80u bu = {.d = b};
	union float80u ru;
	uint16_t sw;

	printf("A: S=%d Exp=%04x Int=%d (QNaN=%d) Sig=%016llx (%.06Le)\n",
	au.ieee.negative, au.ieee.exponent, au.ieee.one,
	au.ieee_nan.quiet_nan, (unsigned long long)au.ieee.mantissa,
	a);
	printf("B: S=%d Exp=%04x Int=%d (QNaN=%d) Sig=%016llx (%.06Le)\n",
	bu.ieee.negative, bu.ieee.exponent, bu.ieee.one,
	bu.ieee_nan.quiet_nan, (unsigned long long)bu.ieee.mantissa,
	b);
	fflush(stdout);

	fninit();
	ru.d = fprem(a, b, &sw);
	psw(sw);

	printf("R : S=%d Exp=%04x Int=%d (QNaN=%d) Sig=%016llx (%.06Le)\n",
	ru.ieee.negative, ru.ieee.exponent, ru.ieee.one,
	ru.ieee_nan.quiet_nan, (unsigned long long)ru.ieee.mantissa,
	ru.d);

	fninit();
	ru.d = fprem1(a, b, &sw);
	psw(sw);

	printf("R1: S=%d Exp=%04x Int=%d (QNaN=%d) Sig=%016llx (%.06Le)\n",
	ru.ieee.negative, ru.ieee.exponent, ru.ieee.one,
	ru.ieee_nan.quiet_nan, (unsigned long long)ru.ieee.mantissa,
	ru.d);

	printf("\n");
	}

	static void do_fprem_stack_underflow(void)
	{
	const long double a = 1.0;
	union float80u ru;
	uint16_t sw;

	fninit();
	asm volatile ("fprem\n"
	"fnstsw %1\n"
	: "=t" (ru.d), "=m" (sw)
	: "0" (a)
	: "st(1)");
	psw(sw);

	printf("R: S=%d Exp=%04x Int=%d (QNaN=%d) Sig=%016llx (%.06Le)\n",
	ru.ieee.negative, ru.ieee.exponent, ru.ieee.one,
	ru.ieee_nan.quiet_nan, (unsigned long long)ru.ieee.mantissa,
	ru.d);
	printf("\n");
	}

	static void test_fprem_cases(void)
	{
	printf("= stack underflow =\n");
	do_fprem_stack_underflow();

	printf("= invalid operation =\n");
	do_fprem(q_nan.d, 1.0);
	do_fprem(s_nan.d, 1.0);
	do_fprem(1.0, 0.0);
	do_fprem(pos_inf.d, 1.0);
	do_fprem(pseudo_pos_inf.d, 1.0);

	printf("= denormal =\n");
	do_fprem(pos_denorm.d, 1.0);
	do_fprem(1.0, pos_denorm.d);

	do_fprem(smallest_positive_norm.d, smallest_positive_norm.d);

	/* printf("= underflow =\n"); */
	/* TODO: Is there a case where FPREM raises underflow? */
	}

	static void test_fprem_pairs(void)
	{
	unsigned long long count;

	unsigned int negative_index_a = 0;
	unsigned int negative_index_b = 0;
	static const unsigned int negative_values[] = {
	0,
	1,
	};

	unsigned int exponent_index_a = 0;
	unsigned int exponent_index_b = 0;
	static const unsigned int exponent_values[] = {
	0,
	1,
	2,
	IEEE854_LONG_DOUBLE_BIAS - 1,
	IEEE854_LONG_DOUBLE_BIAS,
	IEEE854_LONG_DOUBLE_BIAS + 1,
	0x7ffd,
	0x7ffe,
	0x7fff,
	};

	unsigned int one_index_a = 0;
	unsigned int one_index_b = 0;
	static const unsigned int one_values[] = {
	0,
	1,
	};

	unsigned int quiet_nan_index_a = 0;
	unsigned int quiet_nan_index_b = 0;
	static const unsigned int quiet_nan_values[] = {
	0,
	1,
	};

	unsigned int mantissa_index_a = 0;
	unsigned int mantissa_index_b = 0;
	static const unsigned long long mantissa_values[] = {
	0,
	1,
	2,
	0x3ffffffffffffffdULL,
	0x3ffffffffffffffeULL,
	0x3fffffffffffffffULL,
	};

	for (count = 0; ; ++count) {
	#define INIT_FIELD(var, field) \
	.ieee_nan.field = field##_values[field##_index_##var]
	const union float80u a = {
	INIT_FIELD(a, negative),
	INIT_FIELD(a, exponent),
	INIT_FIELD(a, one),
	INIT_FIELD(a, quiet_nan),
	INIT_FIELD(a, mantissa),
	};
	const union float80u b = {
	INIT_FIELD(b, negative),
	INIT_FIELD(b, exponent),
	INIT_FIELD(b, one),
	INIT_FIELD(b, quiet_nan),
	INIT_FIELD(b, mantissa),
	};
	#undef INIT_FIELD

	do_fprem(a.d, b.d);

	int carry = 1;
	#define CARRY_INTO(var, field) do { \
	if (carry) { \
	if (++field##_index_##var == ARRAY_SIZE(field##_values)) { \
	field##_index_##var = 0; \
	} else { \
	carry = 0; \
	} \
	} \
	} while (0)
	CARRY_INTO(b, mantissa);
	CARRY_INTO(b, quiet_nan);
	CARRY_INTO(b, one);
	CARRY_INTO(b, exponent);
	CARRY_INTO(b, negative);
	CARRY_INTO(a, mantissa);
	CARRY_INTO(a, quiet_nan);
	CARRY_INTO(a, one);
	CARRY_INTO(a, exponent);
	CARRY_INTO(a, negative);
	#undef CARRY_INTO

	if (carry) {
	break;
	}
	}

	fprintf(stderr, "test-i386-fprem: tested %llu cases\n", count);
	}

	int main(int argc, char **argv)
	{
	test_fprem_cases();
	test_fprem_pairs();
	return 0;
	}