target-openrisc: Write back result before FPE exception

The architecture manual is unclear about this, but the or1ksim
does writeback before the exception.  This requires splitting
the helpers in half, with the exception raised by the second.

Acked-by: Stafford Horne <shorne@gmail.com>
Reviewed-by: Bastian Koppelmann <kbastian@mail.uni-paderborn.de>
Signed-off-by: Richard Henderson <rth@twiddle.net>

1 files changed, 49 insertions, 203 deletions

diff --git a/target/openrisc/fpu_helper.c b/target/openrisc/fpu_helper.c
index 977a1e8e55..265ce13337 100644
--- a/target/openrisc/fpu_helper.c
+++ b/target/openrisc/fpu_helper.c
@@ -24,121 +24,70 @@
 #include "exception.h"
 #include "fpu/softfloat.h"
 
-static inline uint32_t ieee_ex_to_openrisc(OpenRISCCPU *cpu, int fexcp)
+static int ieee_ex_to_openrisc(int fexcp)
 {
     int ret = 0;
-    if (fexcp) {
-        if (fexcp & float_flag_invalid) {
-            cpu->env.fpcsr |= FPCSR_IVF;
-            ret = 1;
-        }
-        if (fexcp & float_flag_overflow) {
-            cpu->env.fpcsr |= FPCSR_OVF;
-            ret = 1;
-        }
-        if (fexcp & float_flag_underflow) {
-            cpu->env.fpcsr |= FPCSR_UNF;
-            ret = 1;
-        }
-        if (fexcp & float_flag_divbyzero) {
-            cpu->env.fpcsr |= FPCSR_DZF;
-            ret = 1;
-        }
-        if (fexcp & float_flag_inexact) {
-            cpu->env.fpcsr |= FPCSR_IXF;
-            ret = 1;
-        }
+    if (fexcp & float_flag_invalid) {
+        ret |= FPCSR_IVF;
+    }
+    if (fexcp & float_flag_overflow) {
+        ret |= FPCSR_OVF;
+    }
+    if (fexcp & float_flag_underflow) {
+        ret |= FPCSR_UNF;
+    }
+    if (fexcp & float_flag_divbyzero) {
+        ret |= FPCSR_DZF;
+    }
+    if (fexcp & float_flag_inexact) {
+        ret |= FPCSR_IXF;
     }
-
     return ret;
 }
 
-static inline void update_fpcsr(OpenRISCCPU *cpu)
+void HELPER(update_fpcsr)(CPUOpenRISCState *env)
 {
-    int tmp = ieee_ex_to_openrisc(cpu,
-                              get_float_exception_flags(&cpu->env.fp_status));
-
-    SET_FP_CAUSE(cpu->env.fpcsr, tmp);
-    if ((GET_FP_ENABLE(cpu->env.fpcsr) & tmp) &&
-        (cpu->env.fpcsr & FPCSR_FPEE)) {
-        helper_exception(&cpu->env, EXCP_FPE);
-    } else {
-        UPDATE_FP_FLAGS(cpu->env.fpcsr, tmp);
+    int tmp = get_float_exception_flags(&env->fp_status);
+
+    if (tmp) {
+        set_float_exception_flags(0, &env->fp_status);
+        tmp = ieee_ex_to_openrisc(tmp);
+        if (tmp) {
+            env->fpcsr |= tmp;
+            if (env->fpcsr & FPCSR_FPEE) {
+                helper_exception(env, EXCP_FPE);
+            }
+        }
     }
 }
 
 uint64_t HELPER(itofd)(CPUOpenRISCState *env, uint64_t val)
 {
-    uint64_t itofd;
-    OpenRISCCPU *cpu = openrisc_env_get_cpu(env);
-
-    set_float_exception_flags(0, &cpu->env.fp_status);
-    itofd = int32_to_float64(val, &cpu->env.fp_status);
-    update_fpcsr(cpu);
-
-    return itofd;
+    return int32_to_float64(val, &env->fp_status);
 }
 
 uint32_t HELPER(itofs)(CPUOpenRISCState *env, uint32_t val)
 {
-    uint32_t itofs;
-    OpenRISCCPU *cpu = openrisc_env_get_cpu(env);
-
-    set_float_exception_flags(0, &cpu->env.fp_status);
-    itofs = int32_to_float32(val, &cpu->env.fp_status);
-    update_fpcsr(cpu);
-
-    return itofs;
+    return int32_to_float32(val, &env->fp_status);
 }
 
 uint64_t HELPER(ftoid)(CPUOpenRISCState *env, uint64_t val)
 {
-    uint64_t ftoid;
-    OpenRISCCPU *cpu = openrisc_env_get_cpu(env);
-
-    set_float_exception_flags(0, &cpu->env.fp_status);
-    ftoid = float32_to_int64(val, &cpu->env.fp_status);
-    update_fpcsr(cpu);
-
-    return ftoid;
+    return float32_to_int64(val, &env->fp_status);
 }
 
 uint32_t HELPER(ftois)(CPUOpenRISCState *env, uint32_t val)
 {
-    uint32_t ftois;
-    OpenRISCCPU *cpu = openrisc_env_get_cpu(env);
-
-    set_float_exception_flags(0, &cpu->env.fp_status);
-    ftois = float32_to_int32(val, &cpu->env.fp_status);
-    update_fpcsr(cpu);
-
-    return ftois;
+    return float32_to_int32(val, &env->fp_status);
 }
 
-#define FLOAT_OP(name, p) void helper_float_##_##p(void)
-
 #define FLOAT_CALC(name)                                                  \
 uint64_t helper_float_ ## name ## _d(CPUOpenRISCState *env,               \
                                      uint64_t fdt0, uint64_t fdt1)        \
-{                                                                         \
-    uint64_t result;                                                      \
-    OpenRISCCPU *cpu = openrisc_env_get_cpu(env);                         \
-    set_float_exception_flags(0, &cpu->env.fp_status);                    \
-    result = float64_ ## name(fdt0, fdt1, &cpu->env.fp_status);           \
-    update_fpcsr(cpu);                                                    \
-    return result;                                                        \
-}                                                                         \
-                                                                          \
+{ return float64_ ## name(fdt0, fdt1, &env->fp_status); }                 \
 uint32_t helper_float_ ## name ## _s(CPUOpenRISCState *env,               \
                                      uint32_t fdt0, uint32_t fdt1)        \
-{                                                                         \
-    uint32_t result;                                                      \
-    OpenRISCCPU *cpu = openrisc_env_get_cpu(env);                         \
-    set_float_exception_flags(0, &cpu->env.fp_status);                    \
-    result = float32_ ## name(fdt0, fdt1, &cpu->env.fp_status);           \
-    update_fpcsr(cpu);                                                    \
-    return result;                                                        \
-}                                                                         \
+{ return float32_ ## name(fdt0, fdt1, &env->fp_status); }
 
 FLOAT_CALC(add)
 FLOAT_CALC(sub)
@@ -151,132 +100,29 @@ FLOAT_CALC(rem)
 uint64_t helper_float_madd_d(CPUOpenRISCState *env, uint64_t a,
                              uint64_t b, uint64_t c)
 {
-    OpenRISCCPU *cpu = openrisc_env_get_cpu(env);
-    uint64_t result;
-    set_float_exception_flags(0, &cpu->env.fp_status);
-    /* Note that or1ksim doesn't use merged operation.  */
-    result = float64_mul(b, c, &cpu->env.fp_status);
-    result = float64_add(result, a, &cpu->env.fp_status);
-    update_fpcsr(cpu);
-    return result;
+    /* Note that or1ksim doesn't use fused operation.  */
+    b = float64_mul(b, c, &env->fp_status);
+    return float64_add(a, b, &env->fp_status);
 }
 
 uint32_t helper_float_madd_s(CPUOpenRISCState *env, uint32_t a,
                              uint32_t b, uint32_t c)
 {
-    OpenRISCCPU *cpu = openrisc_env_get_cpu(env);
-    uint32_t result;
-    set_float_exception_flags(0, &cpu->env.fp_status);
-    /* Note that or1ksim doesn't use merged operation.  */
-    result = float32_mul(b, c, &cpu->env.fp_status);
-    result = float32_add(result, a, &cpu->env.fp_status);
-    update_fpcsr(cpu);
-    return result;
+    /* Note that or1ksim doesn't use fused operation.  */
+    b = float32_mul(b, c, &env->fp_status);
+    return float32_add(a, b, &env->fp_status);
 }
 
 
-#define FLOAT_CMP(name)                                                   \
-uint64_t helper_float_ ## name ## _d(CPUOpenRISCState *env,               \
-                                     uint64_t fdt0, uint64_t fdt1)        \
-{                                                                         \
-    int res;                                                              \
-    OpenRISCCPU *cpu = openrisc_env_get_cpu(env);                         \
-    set_float_exception_flags(0, &cpu->env.fp_status);                    \
-    res = float64_ ## name(fdt0, fdt1, &cpu->env.fp_status);              \
-    update_fpcsr(cpu);                                                    \
-    return res;                                                           \
-}                                                                         \
-                                                                          \
-uint32_t helper_float_ ## name ## _s(CPUOpenRISCState *env,               \
-                                             uint32_t fdt0, uint32_t fdt1)\
-{                                                                         \
-    int res;                                                              \
-    OpenRISCCPU *cpu = openrisc_env_get_cpu(env);                         \
-    set_float_exception_flags(0, &cpu->env.fp_status);                    \
-    res = float32_ ## name(fdt0, fdt1, &cpu->env.fp_status);              \
-    update_fpcsr(cpu);                                                    \
-    return res;                                                           \
-}
+#define FLOAT_CMP(name, impl)                                             \
+target_ulong helper_float_ ## name ## _d(CPUOpenRISCState *env,           \
+                                         uint64_t fdt0, uint64_t fdt1)    \
+{ return float64_ ## impl(fdt0, fdt1, &env->fp_status); }                 \
+target_ulong helper_float_ ## name ## _s(CPUOpenRISCState *env,           \
+                                         uint32_t fdt0, uint32_t fdt1)    \
+{ return float32_ ## impl(fdt0, fdt1, &env->fp_status); }
 
-FLOAT_CMP(le)
-FLOAT_CMP(eq)
-FLOAT_CMP(lt)
+FLOAT_CMP(le, le)
+FLOAT_CMP(lt, lt)
+FLOAT_CMP(eq, eq_quiet)
 #undef FLOAT_CMP
-
-
-#define FLOAT_CMPNE(name)                                                 \
-uint64_t helper_float_ ## name ## _d(CPUOpenRISCState *env,               \
-                                     uint64_t fdt0, uint64_t fdt1)        \
-{                                                                         \
-    int res;                                                              \
-    OpenRISCCPU *cpu = openrisc_env_get_cpu(env);                         \
-    set_float_exception_flags(0, &cpu->env.fp_status);                    \
-    res = !float64_eq_quiet(fdt0, fdt1, &cpu->env.fp_status);             \
-    update_fpcsr(cpu);                                                    \
-    return res;                                                           \
-}                                                                         \
-                                                                          \
-uint32_t helper_float_ ## name ## _s(CPUOpenRISCState *env,               \
-                                     uint32_t fdt0, uint32_t fdt1)        \
-{                                                                         \
-    int res;                                                              \
-    OpenRISCCPU *cpu = openrisc_env_get_cpu(env);                         \
-    set_float_exception_flags(0, &cpu->env.fp_status);                    \
-    res = !float32_eq_quiet(fdt0, fdt1, &cpu->env.fp_status);             \
-    update_fpcsr(cpu);                                                    \
-    return res;                                                           \
-}
-
-FLOAT_CMPNE(ne)
-#undef FLOAT_CMPNE
-
-#define FLOAT_CMPGT(name)                                                 \
-uint64_t helper_float_ ## name ## _d(CPUOpenRISCState *env,               \
-                                     uint64_t fdt0, uint64_t fdt1)        \
-{                                                                         \
-    int res;                                                              \
-    OpenRISCCPU *cpu = openrisc_env_get_cpu(env);                         \
-    set_float_exception_flags(0, &cpu->env.fp_status);                    \
-    res = !float64_le(fdt0, fdt1, &cpu->env.fp_status);                   \
-    update_fpcsr(cpu);                                                    \
-    return res;                                                           \
-}                                                                         \
-                                                                          \
-uint32_t helper_float_ ## name ## _s(CPUOpenRISCState *env,               \
-                                     uint32_t fdt0, uint32_t fdt1)        \
-{                                                                         \
-    int res;                                                              \
-    OpenRISCCPU *cpu = openrisc_env_get_cpu(env);                         \
-    set_float_exception_flags(0, &cpu->env.fp_status);                    \
-    res = !float32_le(fdt0, fdt1, &cpu->env.fp_status);                   \
-    update_fpcsr(cpu);                                                    \
-    return res;                                                           \
-}
-FLOAT_CMPGT(gt)
-#undef FLOAT_CMPGT
-
-#define FLOAT_CMPGE(name)                                                 \
-uint64_t helper_float_ ## name ## _d(CPUOpenRISCState *env,               \
-                                     uint64_t fdt0, uint64_t fdt1)        \
-{                                                                         \
-    int res;                                                              \
-    OpenRISCCPU *cpu = openrisc_env_get_cpu(env);                         \
-    set_float_exception_flags(0, &cpu->env.fp_status);                    \
-    res = !float64_lt(fdt0, fdt1, &cpu->env.fp_status);                   \
-    update_fpcsr(cpu);                                                    \
-    return res;                                                           \
-}                                                                         \
-                                                                          \
-uint32_t helper_float_ ## name ## _s(CPUOpenRISCState *env,               \
-                                     uint32_t fdt0, uint32_t fdt1)        \
-{                                                                         \
-    int res;                                                              \
-    OpenRISCCPU *cpu = openrisc_env_get_cpu(env);                         \
-    set_float_exception_flags(0, &cpu->env.fp_status);                    \
-    res = !float32_lt(fdt0, fdt1, &cpu->env.fp_status);                   \
-    update_fpcsr(cpu);                                                    \
-    return res;                                                           \
-}
-
-FLOAT_CMPGE(ge)
-#undef FLOAT_CMPGE