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-rw-r--r--target-alpha/vax_helper.c353
1 files changed, 353 insertions, 0 deletions
diff --git a/target-alpha/vax_helper.c b/target-alpha/vax_helper.c
new file mode 100644
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--- /dev/null
+++ b/target-alpha/vax_helper.c
@@ -0,0 +1,353 @@
+/*
+ * Helpers for vax floating point instructions.
+ *
+ * Copyright (c) 2007 Jocelyn Mayer
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "cpu.h"
+#include "exec/helper-proto.h"
+#include "fpu/softfloat.h"
+
+#define FP_STATUS (env->fp_status)
+
+
+/* F floating (VAX) */
+static uint64_t float32_to_f(float32 fa)
+{
+ uint64_t r, exp, mant, sig;
+ CPU_FloatU a;
+
+ a.f = fa;
+ sig = ((uint64_t)a.l & 0x80000000) << 32;
+ exp = (a.l >> 23) & 0xff;
+ mant = ((uint64_t)a.l & 0x007fffff) << 29;
+
+ if (exp == 255) {
+ /* NaN or infinity */
+ r = 1; /* VAX dirty zero */
+ } else if (exp == 0) {
+ if (mant == 0) {
+ /* Zero */
+ r = 0;
+ } else {
+ /* Denormalized */
+ r = sig | ((exp + 1) << 52) | mant;
+ }
+ } else {
+ if (exp >= 253) {
+ /* Overflow */
+ r = 1; /* VAX dirty zero */
+ } else {
+ r = sig | ((exp + 2) << 52);
+ }
+ }
+
+ return r;
+}
+
+static float32 f_to_float32(CPUAlphaState *env, uintptr_t retaddr, uint64_t a)
+{
+ uint32_t exp, mant_sig;
+ CPU_FloatU r;
+
+ exp = ((a >> 55) & 0x80) | ((a >> 52) & 0x7f);
+ mant_sig = ((a >> 32) & 0x80000000) | ((a >> 29) & 0x007fffff);
+
+ if (unlikely(!exp && mant_sig)) {
+ /* Reserved operands / Dirty zero */
+ dynamic_excp(env, retaddr, EXCP_OPCDEC, 0);
+ }
+
+ if (exp < 3) {
+ /* Underflow */
+ r.l = 0;
+ } else {
+ r.l = ((exp - 2) << 23) | mant_sig;
+ }
+
+ return r.f;
+}
+
+uint32_t helper_f_to_memory(uint64_t a)
+{
+ uint32_t r;
+ r = (a & 0x00001fffe0000000ull) >> 13;
+ r |= (a & 0x07ffe00000000000ull) >> 45;
+ r |= (a & 0xc000000000000000ull) >> 48;
+ return r;
+}
+
+uint64_t helper_memory_to_f(uint32_t a)
+{
+ uint64_t r;
+ r = ((uint64_t)(a & 0x0000c000)) << 48;
+ r |= ((uint64_t)(a & 0x003fffff)) << 45;
+ r |= ((uint64_t)(a & 0xffff0000)) << 13;
+ if (!(a & 0x00004000)) {
+ r |= 0x7ll << 59;
+ }
+ return r;
+}
+
+/* ??? Emulating VAX arithmetic with IEEE arithmetic is wrong. We should
+ either implement VAX arithmetic properly or just signal invalid opcode. */
+
+uint64_t helper_addf(CPUAlphaState *env, uint64_t a, uint64_t b)
+{
+ float32 fa, fb, fr;
+
+ fa = f_to_float32(env, GETPC(), a);
+ fb = f_to_float32(env, GETPC(), b);
+ fr = float32_add(fa, fb, &FP_STATUS);
+ return float32_to_f(fr);
+}
+
+uint64_t helper_subf(CPUAlphaState *env, uint64_t a, uint64_t b)
+{
+ float32 fa, fb, fr;
+
+ fa = f_to_float32(env, GETPC(), a);
+ fb = f_to_float32(env, GETPC(), b);
+ fr = float32_sub(fa, fb, &FP_STATUS);
+ return float32_to_f(fr);
+}
+
+uint64_t helper_mulf(CPUAlphaState *env, uint64_t a, uint64_t b)
+{
+ float32 fa, fb, fr;
+
+ fa = f_to_float32(env, GETPC(), a);
+ fb = f_to_float32(env, GETPC(), b);
+ fr = float32_mul(fa, fb, &FP_STATUS);
+ return float32_to_f(fr);
+}
+
+uint64_t helper_divf(CPUAlphaState *env, uint64_t a, uint64_t b)
+{
+ float32 fa, fb, fr;
+
+ fa = f_to_float32(env, GETPC(), a);
+ fb = f_to_float32(env, GETPC(), b);
+ fr = float32_div(fa, fb, &FP_STATUS);
+ return float32_to_f(fr);
+}
+
+uint64_t helper_sqrtf(CPUAlphaState *env, uint64_t t)
+{
+ float32 ft, fr;
+
+ ft = f_to_float32(env, GETPC(), t);
+ fr = float32_sqrt(ft, &FP_STATUS);
+ return float32_to_f(fr);
+}
+
+
+/* G floating (VAX) */
+static uint64_t float64_to_g(float64 fa)
+{
+ uint64_t r, exp, mant, sig;
+ CPU_DoubleU a;
+
+ a.d = fa;
+ sig = a.ll & 0x8000000000000000ull;
+ exp = (a.ll >> 52) & 0x7ff;
+ mant = a.ll & 0x000fffffffffffffull;
+
+ if (exp == 2047) {
+ /* NaN or infinity */
+ r = 1; /* VAX dirty zero */
+ } else if (exp == 0) {
+ if (mant == 0) {
+ /* Zero */
+ r = 0;
+ } else {
+ /* Denormalized */
+ r = sig | ((exp + 1) << 52) | mant;
+ }
+ } else {
+ if (exp >= 2045) {
+ /* Overflow */
+ r = 1; /* VAX dirty zero */
+ } else {
+ r = sig | ((exp + 2) << 52);
+ }
+ }
+
+ return r;
+}
+
+static float64 g_to_float64(CPUAlphaState *env, uintptr_t retaddr, uint64_t a)
+{
+ uint64_t exp, mant_sig;
+ CPU_DoubleU r;
+
+ exp = (a >> 52) & 0x7ff;
+ mant_sig = a & 0x800fffffffffffffull;
+
+ if (!exp && mant_sig) {
+ /* Reserved operands / Dirty zero */
+ dynamic_excp(env, retaddr, EXCP_OPCDEC, 0);
+ }
+
+ if (exp < 3) {
+ /* Underflow */
+ r.ll = 0;
+ } else {
+ r.ll = ((exp - 2) << 52) | mant_sig;
+ }
+
+ return r.d;
+}
+
+uint64_t helper_g_to_memory(uint64_t a)
+{
+ uint64_t r;
+ r = (a & 0x000000000000ffffull) << 48;
+ r |= (a & 0x00000000ffff0000ull) << 16;
+ r |= (a & 0x0000ffff00000000ull) >> 16;
+ r |= (a & 0xffff000000000000ull) >> 48;
+ return r;
+}
+
+uint64_t helper_memory_to_g(uint64_t a)
+{
+ uint64_t r;
+ r = (a & 0x000000000000ffffull) << 48;
+ r |= (a & 0x00000000ffff0000ull) << 16;
+ r |= (a & 0x0000ffff00000000ull) >> 16;
+ r |= (a & 0xffff000000000000ull) >> 48;
+ return r;
+}
+
+uint64_t helper_addg(CPUAlphaState *env, uint64_t a, uint64_t b)
+{
+ float64 fa, fb, fr;
+
+ fa = g_to_float64(env, GETPC(), a);
+ fb = g_to_float64(env, GETPC(), b);
+ fr = float64_add(fa, fb, &FP_STATUS);
+ return float64_to_g(fr);
+}
+
+uint64_t helper_subg(CPUAlphaState *env, uint64_t a, uint64_t b)
+{
+ float64 fa, fb, fr;
+
+ fa = g_to_float64(env, GETPC(), a);
+ fb = g_to_float64(env, GETPC(), b);
+ fr = float64_sub(fa, fb, &FP_STATUS);
+ return float64_to_g(fr);
+}
+
+uint64_t helper_mulg(CPUAlphaState *env, uint64_t a, uint64_t b)
+{
+ float64 fa, fb, fr;
+
+ fa = g_to_float64(env, GETPC(), a);
+ fb = g_to_float64(env, GETPC(), b);
+ fr = float64_mul(fa, fb, &FP_STATUS);
+ return float64_to_g(fr);
+}
+
+uint64_t helper_divg(CPUAlphaState *env, uint64_t a, uint64_t b)
+{
+ float64 fa, fb, fr;
+
+ fa = g_to_float64(env, GETPC(), a);
+ fb = g_to_float64(env, GETPC(), b);
+ fr = float64_div(fa, fb, &FP_STATUS);
+ return float64_to_g(fr);
+}
+
+uint64_t helper_sqrtg(CPUAlphaState *env, uint64_t a)
+{
+ float64 fa, fr;
+
+ fa = g_to_float64(env, GETPC(), a);
+ fr = float64_sqrt(fa, &FP_STATUS);
+ return float64_to_g(fr);
+}
+
+uint64_t helper_cmpgeq(CPUAlphaState *env, uint64_t a, uint64_t b)
+{
+ float64 fa, fb;
+
+ fa = g_to_float64(env, GETPC(), a);
+ fb = g_to_float64(env, GETPC(), b);
+
+ if (float64_eq_quiet(fa, fb, &FP_STATUS)) {
+ return 0x4000000000000000ULL;
+ } else {
+ return 0;
+ }
+}
+
+uint64_t helper_cmpgle(CPUAlphaState *env, uint64_t a, uint64_t b)
+{
+ float64 fa, fb;
+
+ fa = g_to_float64(env, GETPC(), a);
+ fb = g_to_float64(env, GETPC(), b);
+
+ if (float64_le(fa, fb, &FP_STATUS)) {
+ return 0x4000000000000000ULL;
+ } else {
+ return 0;
+ }
+}
+
+uint64_t helper_cmpglt(CPUAlphaState *env, uint64_t a, uint64_t b)
+{
+ float64 fa, fb;
+
+ fa = g_to_float64(env, GETPC(), a);
+ fb = g_to_float64(env, GETPC(), b);
+
+ if (float64_lt(fa, fb, &FP_STATUS)) {
+ return 0x4000000000000000ULL;
+ } else {
+ return 0;
+ }
+}
+
+uint64_t helper_cvtqf(CPUAlphaState *env, uint64_t a)
+{
+ float32 fr = int64_to_float32(a, &FP_STATUS);
+ return float32_to_f(fr);
+}
+
+uint64_t helper_cvtgf(CPUAlphaState *env, uint64_t a)
+{
+ float64 fa;
+ float32 fr;
+
+ fa = g_to_float64(env, GETPC(), a);
+ fr = float64_to_float32(fa, &FP_STATUS);
+ return float32_to_f(fr);
+}
+
+uint64_t helper_cvtgq(CPUAlphaState *env, uint64_t a)
+{
+ float64 fa = g_to_float64(env, GETPC(), a);
+ return float64_to_int64_round_to_zero(fa, &FP_STATUS);
+}
+
+uint64_t helper_cvtqg(CPUAlphaState *env, uint64_t a)
+{
+ float64 fr;
+ fr = int64_to_float64(a, &FP_STATUS);
+ return float64_to_g(fr);
+}
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