target/arm: Implement FMMLA (FP8 to FP16) for AdvSIMD

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20260609192110.752384-44-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

diff --git a/target/arm/cpu-features.h b/target/arm/cpu-features.h
index 67e9c3bd33816d46af1b951d5bf95193cb3146c1..753799008ce0e7d86b625cea45e908f2a892a608 100644 (file)
--- a/target/arm/cpu-features.h
+++ b/target/arm/cpu-features.h
@@ -1650,6 +1650,11 @@ static inline bool isar_feature_aa64_f8mm8(const ARMISARegisters *id)
     return FIELD_EX64_IDREG(id, ID_AA64FPFR0, F8MM8);
 }
 
+static inline bool isar_feature_aa64_f8mm4(const ARMISARegisters *id)
+{
+    return FIELD_EX64_IDREG(id, ID_AA64FPFR0, F8MM4);
+}
+
 /*
  * Combinations of feature tests, for ease of use with TRANS_FEAT.
  */

diff --git a/target/arm/tcg/a64.decode b/target/arm/tcg/a64.decode
index 6922e910103722e165ff3a0eb8eede7ad9d67b45..28cd1faf61acb6eba0e8f6c4f37fa360fbcdd53a 100644 (file)
--- a/target/arm/tcg/a64.decode
+++ b/target/arm/tcg/a64.decode
@@ -1228,6 +1228,7 @@ FDOT_sb_v       0.00 1110 000 ..... 11111 1 ..... ..... @qrrr_s
 FDOT_hb_v       0.00 1110 010 ..... 11111 1 ..... ..... @qrrr_h
 
 FMMLA_sb        0110 1110 100 ..... 11101 1 ..... ..... @rrr_q1e0
+FMMLA_hb        0110 1110 000 ..... 11101 1 ..... ..... @rrr_q1e0
 
 ### Advanced SIMD scalar x indexed element
 

diff --git a/target/arm/tcg/fp8_helper.c b/target/arm/tcg/fp8_helper.c
index b9d4ba3b6afd835bae169d6e7f5fdaf1867fe9f2..bd0877071b81e30890d288d10939ac5c2986d957 100644 (file)
--- a/target/arm/tcg/fp8_helper.c
+++ b/target/arm/tcg/fp8_helper.c
@@ -832,3 +832,28 @@ void HELPER(gvec_fmmla_sb)(void *vd, void *vn, void *vm,
 
     clear_tail(vd, oprsz, simd_maxsz(desc));
 }
+
+void HELPER(gvec_fmmla_hb)(void *vd, void *vn, void *vm,
+                           CPUARMState *env, uint32_t desc)
+{
+    FP8MulContext ctx = fp8_mul_start(env, 0xf);
+    size_t oprsz = simd_oprsz(desc);
+    size_t nseg = oprsz / 8;
+    uint32_t *n = vn;
+    uint32_t *m = vm;
+    float16 *d = vd;
+
+    for (size_t seg = 0; seg < nseg; seg++, d += 4, n += 2, m += 2) {
+        float16 d0 = f8dotadd_h(n[H4(0)], m[H4(0)], 4, d[H2(0)], &ctx);
+        float16 d1 = f8dotadd_h(n[H4(0)], m[H4(1)], 4, d[H2(1)], &ctx);
+        float16 d2 = f8dotadd_h(n[H4(1)], m[H4(0)], 4, d[H2(2)], &ctx);
+        float16 d3 = f8dotadd_h(n[H4(1)], m[H4(1)], 4, d[H2(3)], &ctx);
+
+        d[H2(0)] = d0;
+        d[H2(1)] = d1;
+        d[H2(2)] = d2;
+        d[H2(3)] = d3;
+    }
+
+    clear_tail(vd, oprsz, simd_maxsz(desc));
+}

diff --git a/target/arm/tcg/helper-fp8-defs.h b/target/arm/tcg/helper-fp8-defs.h
index 3c74f02022e26df2c3a459075b6575ce3088bca4..e942308af4568d526769253dca817525ef9a9419 100644 (file)
--- a/target/arm/tcg/helper-fp8-defs.h
+++ b/target/arm/tcg/helper-fp8-defs.h
@@ -37,3 +37,4 @@ DEF_HELPER_FLAGS_5(gvec_fdot_hb, TCG_CALL_NO_RWG, void, ptr, ptr, ptr, env, i32)
 DEF_HELPER_FLAGS_5(gvec_fdot_idx_hb, TCG_CALL_NO_RWG, void, ptr, ptr, ptr, env, i32)
 
 DEF_HELPER_FLAGS_5(gvec_fmmla_sb, TCG_CALL_NO_RWG, void, ptr, ptr, ptr, env, i32)
+DEF_HELPER_FLAGS_5(gvec_fmmla_hb, TCG_CALL_NO_RWG, void, ptr, ptr, ptr, env, i32)

diff --git a/target/arm/tcg/translate-a64.c b/target/arm/tcg/translate-a64.c
index ffe59b94718ced1cb1ab50d7e8953ed7822d4dc9..227719ef25b1031212b61cb46bf66af385c633e4 100644 (file)
--- a/target/arm/tcg/translate-a64.c
+++ b/target/arm/tcg/translate-a64.c
@@ -7516,6 +7516,7 @@ static bool do_f8dot(DisasContext *s, arg_qrrr_e *a,
 TRANS_FEAT(FDOT_sb_v, aa64_f8dp4, do_f8dot, a, gen_helper_gvec_fdot_sb)
 TRANS_FEAT(FDOT_hb_v, aa64_f8dp2, do_f8dot, a, gen_helper_gvec_fdot_hb)
 TRANS_FEAT(FMMLA_sb, aa64_f8mm8, do_f8dot, a, gen_helper_gvec_fmmla_sb)
+TRANS_FEAT(FMMLA_hb, aa64_f8mm4, do_f8dot, a, gen_helper_gvec_fmmla_hb)
 
 static bool do_f8dot_idx(DisasContext *s, arg_qrrx_e *a,
                          gen_helper_gvec_3_ptr *fn)