target-alpha: Move VAX helpers to a new file

Keep the IEEE and VAX floating point emulation separate.

Signed-off-by: Richard Henderson <rth@twiddle.net>

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
index 0000000000..2e2f49971b
--- /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);
+}