target/ppc: Add helpers for fadds, fsubs, fdivs

Use float64r32_{add,sub,div}.  Fixes a double-rounding issue with
performing the compuation in float64 and then rounding afterward.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20211119160502.17432-31-richard.henderson@linaro.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>

1 files changed, 40 insertions, 0 deletions

diff --git a/target/ppc/fpu_helper.c b/target/ppc/fpu_helper.c
index 07e1695b07..c36cf05d80 100644
--- a/target/ppc/fpu_helper.c
+++ b/target/ppc/fpu_helper.c
@@ -521,6 +521,18 @@ float64 helper_fadd(CPUPPCState *env, float64 arg1, float64 arg2)
     return ret;
 }
 
+/* fadds - fadds. */
+float64 helper_fadds(CPUPPCState *env, float64 arg1, float64 arg2)
+{
+    float64 ret = float64r32_add(arg1, arg2, &env->fp_status);
+    int flags = get_float_exception_flags(&env->fp_status);
+
+    if (unlikely(flags & float_flag_invalid)) {
+        float_invalid_op_addsub(env, flags, 1, GETPC());
+    }
+    return ret;
+}
+
 /* fsub - fsub. */
 float64 helper_fsub(CPUPPCState *env, float64 arg1, float64 arg2)
 {
@@ -534,6 +546,18 @@ float64 helper_fsub(CPUPPCState *env, float64 arg1, float64 arg2)
     return ret;
 }
 
+/* fsubs - fsubs. */
+float64 helper_fsubs(CPUPPCState *env, float64 arg1, float64 arg2)
+{
+    float64 ret = float64r32_sub(arg1, arg2, &env->fp_status);
+    int flags = get_float_exception_flags(&env->fp_status);
+
+    if (unlikely(flags & float_flag_invalid)) {
+        float_invalid_op_addsub(env, flags, 1, GETPC());
+    }
+    return ret;
+}
+
 static void float_invalid_op_mul(CPUPPCState *env, int flags,
                                  bool set_fprc, uintptr_t retaddr)
 {
@@ -585,6 +609,22 @@ float64 helper_fdiv(CPUPPCState *env, float64 arg1, float64 arg2)
     return ret;
 }
 
+/* fdivs - fdivs. */
+float64 helper_fdivs(CPUPPCState *env, float64 arg1, float64 arg2)
+{
+    float64 ret = float64r32_div(arg1, arg2, &env->fp_status);
+    int flags = get_float_exception_flags(&env->fp_status);
+
+    if (unlikely(flags & float_flag_invalid)) {
+        float_invalid_op_div(env, flags, 1, GETPC());
+    }
+    if (unlikely(flags & float_flag_divbyzero)) {
+        float_zero_divide_excp(env, GETPC());
+    }
+
+    return ret;
+}
+
 static uint64_t float_invalid_cvt(CPUPPCState *env, int flags,
                                   uint64_t ret, uint64_t ret_nan,
                                   bool set_fprc, uintptr_t retaddr)