[PATCH 67/76] target/arm: Handle FPCR.AH in SVE FTMAD

[Peter Maydell]

The negation step in the SVE FTMAD insn mustn't negate a NaN when
FPCR.AH is set.  Pass FPCR.AH to the helper via the SIMD data field
and use that to determine whether to do the negation.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
---
 target/arm/tcg/sve_helper.c    | 21 +++++++++++++++------
 target/arm/tcg/translate-sve.c |  3 ++-
 2 files changed, 17 insertions(+), 7 deletions(-)

diff --git a/target/arm/tcg/sve_helper.c b/target/arm/tcg/sve_helper.c
index a39a3ed0cf9..3f38e078291 100644
--- a/target/arm/tcg/sve_helper.c
+++ b/target/arm/tcg/sve_helper.c
@@ -5143,13 +5143,16 @@ void HELPER(sve_ftmad_h)(void *vd, void *vn, void *vm,
         0x3c00, 0xb800, 0x293a, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000,
     };
     intptr_t i, opr_sz = simd_oprsz(desc) / sizeof(float16);
-    intptr_t x = simd_data(desc);
+    intptr_t x = extract32(desc, SIMD_DATA_SHIFT, 3);
+    bool fpcr_ah = extract32(desc, SIMD_DATA_SHIFT + 3, 1);
     float16 *d = vd, *n = vn, *m = vm;
     for (i = 0; i < opr_sz; i++) {
         float16 mm = m[i];
         intptr_t xx = x;
         if (float16_is_neg(mm)) {
-            mm = float16_abs(mm);
+            if (!(fpcr_ah && float16_is_any_nan(mm))) {
+                mm = float16_abs(mm);
+            }
             xx += 8;
         }
         d[i] = float16_muladd(n[i], mm, coeff[xx], 0, s);
@@ -5166,13 +5169,16 @@ void HELPER(sve_ftmad_s)(void *vd, void *vn, void *vm,
         0x37cd37cc, 0x00000000, 0x00000000, 0x00000000,
     };
     intptr_t i, opr_sz = simd_oprsz(desc) / sizeof(float32);
-    intptr_t x = simd_data(desc);
+    intptr_t x = extract32(desc, SIMD_DATA_SHIFT, 3);
+    bool fpcr_ah = extract32(desc, SIMD_DATA_SHIFT + 3, 1);
     float32 *d = vd, *n = vn, *m = vm;
     for (i = 0; i < opr_sz; i++) {
         float32 mm = m[i];
         intptr_t xx = x;
         if (float32_is_neg(mm)) {
-            mm = float32_abs(mm);
+            if (!(fpcr_ah && float32_is_any_nan(mm))) {
+                mm = float32_abs(mm);
+            }
             xx += 8;
         }
         d[i] = float32_muladd(n[i], mm, coeff[xx], 0, s);
@@ -5193,13 +5199,16 @@ void HELPER(sve_ftmad_d)(void *vd, void *vn, void *vm,
         0x3e21ee96d2641b13ull, 0xbda8f76380fbb401ull,
     };
     intptr_t i, opr_sz = simd_oprsz(desc) / sizeof(float64);
-    intptr_t x = simd_data(desc);
+    intptr_t x = extract32(desc, SIMD_DATA_SHIFT, 3);
+    bool fpcr_ah = extract32(desc, SIMD_DATA_SHIFT + 3, 1);
     float64 *d = vd, *n = vn, *m = vm;
     for (i = 0; i < opr_sz; i++) {
         float64 mm = m[i];
         intptr_t xx = x;
         if (float64_is_neg(mm)) {
-            mm = float64_abs(mm);
+            if (!(fpcr_ah && float64_is_any_nan(mm))) {
+                mm = float64_abs(mm);
+            }
             xx += 8;
         }
         d[i] = float64_muladd(n[i], mm, coeff[xx], 0, s);
diff --git a/target/arm/tcg/translate-sve.c b/target/arm/tcg/translate-sve.c
index 2d70b0faad2..26bdda8f96e 100644
--- a/target/arm/tcg/translate-sve.c
+++ b/target/arm/tcg/translate-sve.c
@@ -3682,7 +3682,8 @@ static gen_helper_gvec_3_ptr * const ftmad_fns[4] = {
     gen_helper_sve_ftmad_s, gen_helper_sve_ftmad_d,
 };
 TRANS_FEAT_NONSTREAMING(FTMAD, aa64_sve, gen_gvec_fpst_zzz,
-                        ftmad_fns[a->esz], a->rd, a->rn, a->rm, a->imm,
+                        ftmad_fns[a->esz], a->rd, a->rn, a->rm,
+                        a->imm | (s->fpcr_ah << 3),
                         a->esz == MO_16 ? FPST_FPCR_F16_A64 : FPST_FPCR_A64)
 
 /*
-- 
2.34.1