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Diffstat (limited to 'target-arm')
-rw-r--r--target-arm/translate.c53
1 files changed, 40 insertions, 13 deletions
diff --git a/target-arm/translate.c b/target-arm/translate.c
index 59190f64ca..a8a3b2cd64 100644
--- a/target-arm/translate.c
+++ b/target-arm/translate.c
@@ -909,6 +909,26 @@ VFP_OP2(div)
#undef VFP_OP2
+static inline void gen_vfp_F1_mul(int dp)
+{
+ /* Like gen_vfp_mul() but put result in F1 */
+ if (dp) {
+ gen_helper_vfp_muld(cpu_F1d, cpu_F0d, cpu_F1d, cpu_env);
+ } else {
+ gen_helper_vfp_muls(cpu_F1s, cpu_F0s, cpu_F1s, cpu_env);
+ }
+}
+
+static inline void gen_vfp_F1_neg(int dp)
+{
+ /* Like gen_vfp_neg() but put result in F1 */
+ if (dp) {
+ gen_helper_vfp_negd(cpu_F1d, cpu_F0d);
+ } else {
+ gen_helper_vfp_negs(cpu_F1s, cpu_F0s);
+ }
+}
+
static inline void gen_vfp_abs(int dp)
{
if (dp)
@@ -3021,27 +3041,34 @@ static int disas_vfp_insn(CPUState * env, DisasContext *s, uint32_t insn)
for (;;) {
/* Perform the calculation. */
switch (op) {
- case 0: /* mac: fd + (fn * fm) */
- gen_vfp_mul(dp);
- gen_mov_F1_vreg(dp, rd);
+ case 0: /* VMLA: fd + (fn * fm) */
+ /* Note that order of inputs to the add matters for NaNs */
+ gen_vfp_F1_mul(dp);
+ gen_mov_F0_vreg(dp, rd);
gen_vfp_add(dp);
break;
- case 1: /* nmac: fd - (fn * fm) */
+ case 1: /* VMLS: fd + -(fn * fm) */
gen_vfp_mul(dp);
- gen_vfp_neg(dp);
- gen_mov_F1_vreg(dp, rd);
+ gen_vfp_F1_neg(dp);
+ gen_mov_F0_vreg(dp, rd);
gen_vfp_add(dp);
break;
- case 2: /* msc: -fd + (fn * fm) */
- gen_vfp_mul(dp);
- gen_mov_F1_vreg(dp, rd);
- gen_vfp_sub(dp);
+ case 2: /* VNMLS: -fd + (fn * fm) */
+ /* Note that it isn't valid to replace (-A + B) with (B - A)
+ * or similar plausible looking simplifications
+ * because this will give wrong results for NaNs.
+ */
+ gen_vfp_F1_mul(dp);
+ gen_mov_F0_vreg(dp, rd);
+ gen_vfp_neg(dp);
+ gen_vfp_add(dp);
break;
- case 3: /* nmsc: -fd - (fn * fm) */
+ case 3: /* VNMLA: -fd + -(fn * fm) */
gen_vfp_mul(dp);
+ gen_vfp_F1_neg(dp);
+ gen_mov_F0_vreg(dp, rd);
gen_vfp_neg(dp);
- gen_mov_F1_vreg(dp, rd);
- gen_vfp_sub(dp);
+ gen_vfp_add(dp);
break;
case 4: /* mul: fn * fm */
gen_vfp_mul(dp);