diff mbox series

[66/76] target/arm: Handle FPCR.AH in SVE FTSSEL

Message ID 20250124162836.2332150-67-peter.maydell@linaro.org
State New
Headers show
Series target/arm: Implement FEAT_AFP and FEAT_RPRES | expand

Commit Message

Peter Maydell Jan. 24, 2025, 4:28 p.m. UTC
The negation step in the SVE FTSSEL 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    | 18 +++++++++++++++---
 target/arm/tcg/translate-sve.c |  4 ++--
 2 files changed, 17 insertions(+), 5 deletions(-)
diff mbox series

Patch

diff --git a/target/arm/tcg/sve_helper.c b/target/arm/tcg/sve_helper.c
index 90bcf680fa4..a39a3ed0cf9 100644
--- a/target/arm/tcg/sve_helper.c
+++ b/target/arm/tcg/sve_helper.c
@@ -2555,6 +2555,7 @@  void HELPER(sve_fexpa_d)(void *vd, void *vn, uint32_t desc)
 void HELPER(sve_ftssel_h)(void *vd, void *vn, void *vm, uint32_t desc)
 {
     intptr_t i, opr_sz = simd_oprsz(desc) / 2;
+    bool fpcr_ah = extract32(desc, SIMD_DATA_SHIFT, 1);
     uint16_t *d = vd, *n = vn, *m = vm;
     for (i = 0; i < opr_sz; i += 1) {
         uint16_t nn = n[i];
@@ -2562,13 +2563,17 @@  void HELPER(sve_ftssel_h)(void *vd, void *vn, void *vm, uint32_t desc)
         if (mm & 1) {
             nn = float16_one;
         }
-        d[i] = nn ^ (mm & 2) << 14;
+        if ((mm & 2) && !(fpcr_ah && float16_is_any_nan(nn))) {
+            nn ^= (1 << 15);
+        }
+        d[i] = nn;
     }
 }
 
 void HELPER(sve_ftssel_s)(void *vd, void *vn, void *vm, uint32_t desc)
 {
     intptr_t i, opr_sz = simd_oprsz(desc) / 4;
+    bool fpcr_ah = extract32(desc, SIMD_DATA_SHIFT, 1);
     uint32_t *d = vd, *n = vn, *m = vm;
     for (i = 0; i < opr_sz; i += 1) {
         uint32_t nn = n[i];
@@ -2576,13 +2581,17 @@  void HELPER(sve_ftssel_s)(void *vd, void *vn, void *vm, uint32_t desc)
         if (mm & 1) {
             nn = float32_one;
         }
-        d[i] = nn ^ (mm & 2) << 30;
+        if ((mm & 2) && !(fpcr_ah && float32_is_any_nan(nn))) {
+            nn ^= (1U << 31);
+        }
+        d[i] = nn;
     }
 }
 
 void HELPER(sve_ftssel_d)(void *vd, void *vn, void *vm, uint32_t desc)
 {
     intptr_t i, opr_sz = simd_oprsz(desc) / 8;
+    bool fpcr_ah = extract32(desc, SIMD_DATA_SHIFT, 1);
     uint64_t *d = vd, *n = vn, *m = vm;
     for (i = 0; i < opr_sz; i += 1) {
         uint64_t nn = n[i];
@@ -2590,7 +2599,10 @@  void HELPER(sve_ftssel_d)(void *vd, void *vn, void *vm, uint32_t desc)
         if (mm & 1) {
             nn = float64_one;
         }
-        d[i] = nn ^ (mm & 2) << 62;
+        if ((mm & 2) && !(fpcr_ah && float64_is_any_nan(nn))) {
+            nn ^= (1ULL << 63);
+        }
+        d[i] = nn;
     }
 }
 
diff --git a/target/arm/tcg/translate-sve.c b/target/arm/tcg/translate-sve.c
index 663634e3a39..2d70b0faad2 100644
--- a/target/arm/tcg/translate-sve.c
+++ b/target/arm/tcg/translate-sve.c
@@ -1238,14 +1238,14 @@  static gen_helper_gvec_2 * const fexpa_fns[4] = {
     gen_helper_sve_fexpa_s, gen_helper_sve_fexpa_d,
 };
 TRANS_FEAT_NONSTREAMING(FEXPA, aa64_sve, gen_gvec_ool_zz,
-                        fexpa_fns[a->esz], a->rd, a->rn, 0)
+                        fexpa_fns[a->esz], a->rd, a->rn, s->fpcr_ah)
 
 static gen_helper_gvec_3 * const ftssel_fns[4] = {
     NULL,                    gen_helper_sve_ftssel_h,
     gen_helper_sve_ftssel_s, gen_helper_sve_ftssel_d,
 };
 TRANS_FEAT_NONSTREAMING(FTSSEL, aa64_sve, gen_gvec_ool_arg_zzz,
-                        ftssel_fns[a->esz], a, 0)
+                        ftssel_fns[a->esz], a, s->fpcr_ah)
 
 /*
  *** SVE Predicate Logical Operations Group