target/arm: Implement CAS and CASP

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20180508151437.4232-10-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

1 files changed, 43 insertions, 0 deletions

diff --git a/target/arm/helper-a64.c b/target/arm/helper-a64.c
index afb25ad20c..549ed3513e 100644
--- a/target/arm/helper-a64.c
+++ b/target/arm/helper-a64.c
@@ -636,6 +636,49 @@ uint64_t HELPER(paired_cmpxchg64_be_parallel)(CPUARMState *env, uint64_t addr,
     return do_paired_cmpxchg64_be(env, addr, new_lo, new_hi, true, GETPC());
 }
 
+/* Writes back the old data into Rs.  */
+void HELPER(casp_le_parallel)(CPUARMState *env, uint32_t rs, uint64_t addr,
+                              uint64_t new_lo, uint64_t new_hi)
+{
+    uintptr_t ra = GETPC();
+#ifndef CONFIG_ATOMIC128
+    cpu_loop_exit_atomic(ENV_GET_CPU(env), ra);
+#else
+    Int128 oldv, cmpv, newv;
+
+    cmpv = int128_make128(env->xregs[rs], env->xregs[rs + 1]);
+    newv = int128_make128(new_lo, new_hi);
+
+    int mem_idx = cpu_mmu_index(env, false);
+    TCGMemOpIdx oi = make_memop_idx(MO_LEQ | MO_ALIGN_16, mem_idx);
+    oldv = helper_atomic_cmpxchgo_le_mmu(env, addr, cmpv, newv, oi, ra);
+
+    env->xregs[rs] = int128_getlo(oldv);
+    env->xregs[rs + 1] = int128_gethi(oldv);
+#endif
+}
+
+void HELPER(casp_be_parallel)(CPUARMState *env, uint32_t rs, uint64_t addr,
+                              uint64_t new_hi, uint64_t new_lo)
+{
+    uintptr_t ra = GETPC();
+#ifndef CONFIG_ATOMIC128
+    cpu_loop_exit_atomic(ENV_GET_CPU(env), ra);
+#else
+    Int128 oldv, cmpv, newv;
+
+    cmpv = int128_make128(env->xregs[rs + 1], env->xregs[rs]);
+    newv = int128_make128(new_lo, new_hi);
+
+    int mem_idx = cpu_mmu_index(env, false);
+    TCGMemOpIdx oi = make_memop_idx(MO_LEQ | MO_ALIGN_16, mem_idx);
+    oldv = helper_atomic_cmpxchgo_be_mmu(env, addr, cmpv, newv, oi, ra);
+
+    env->xregs[rs + 1] = int128_getlo(oldv);
+    env->xregs[rs] = int128_gethi(oldv);
+#endif
+}
+
 /*
  * AdvSIMD half-precision
  */