target-hppa: Implement loads and stores

Signed-off-by: Richard Henderson <rth@twiddle.net>

target/hppa/helper.h

@@ -2,4 +2,7 @@ DEF_HELPER_2(excp, noreturn, env, int)
 DEF_HELPER_FLAGS_2(tsv, TCG_CALL_NO_WG, void, env, tl)
 DEF_HELPER_FLAGS_2(tcond, TCG_CALL_NO_WG, void, env, tl)
 
+DEF_HELPER_FLAGS_3(stby_b, TCG_CALL_NO_WG, void, env, tl, tl)
+DEF_HELPER_FLAGS_3(stby_e, TCG_CALL_NO_WG, void, env, tl, tl)
+
 DEF_HELPER_FLAGS_1(loaded_fr0, TCG_CALL_NO_RWG, void, env)

target/hppa/op_helper.c

@@ -21,6 +21,7 @@
 #include "cpu.h"
 #include "exec/exec-all.h"
 #include "exec/helper-proto.h"
+#include "exec/cpu_ldst.h"
 
 void QEMU_NORETURN HELPER(excp)(CPUHPPAState *env, int excp)
 {
@@ -54,6 +55,83 @@ void HELPER(tcond)(CPUHPPAState *env, target_ulong cond)
     }
 }
 
+static void atomic_store_3(CPUHPPAState *env, target_ulong addr, uint32_t val,
+                           uint32_t mask, uintptr_t ra)
+{
+    uint32_t old, new, cmp;
+
+#ifdef CONFIG_USER_ONLY
+    uint32_t *haddr = g2h(addr - 1);
+    old = *haddr;
+    while (1) {
+        new = (old & ~mask) | (val & mask);
+        cmp = atomic_cmpxchg(haddr, old, new);
+        if (cmp == old) {
+            return;
+        }
+        old = cmp;
+    }
+#else
+#error "Not implemented."
+#endif
+}
+
+void HELPER(stby_b)(CPUHPPAState *env, target_ulong addr, target_ulong val)
+{
+    uintptr_t ra = GETPC();
+
+    switch (addr & 3) {
+    case 3:
+        cpu_stb_data_ra(env, addr, val, ra);
+        break;
+    case 2:
+        cpu_stw_data_ra(env, addr, val, ra);
+        break;
+    case 1:
+        /* The 3 byte store must appear atomic.  */
+        if (parallel_cpus) {
+            atomic_store_3(env, addr, val, 0x00ffffffu, ra);
+        } else {
+            cpu_stb_data_ra(env, addr, val >> 16, ra);
+            cpu_stw_data_ra(env, addr + 1, val, ra);
+        }
+        break;
+    default:
+        cpu_stl_data_ra(env, addr, val, ra);
+        break;
+    }
+}
+
+void HELPER(stby_e)(CPUHPPAState *env, target_ulong addr, target_ulong val)
+{
+    uintptr_t ra = GETPC();
+
+    switch (addr & 3) {
+    case 3:
+        /* The 3 byte store must appear atomic.  */
+        if (parallel_cpus) {
+            atomic_store_3(env, addr - 3, val, 0xffffff00u, ra);
+        } else {
+            cpu_stw_data_ra(env, addr - 3, val >> 16, ra);
+            cpu_stb_data_ra(env, addr - 1, val >> 8, ra);
+        }
+        break;
+    case 2:
+        cpu_stw_data_ra(env, addr - 2, val >> 16, ra);
+        break;
+    case 1:
+        cpu_stb_data_ra(env, addr - 1, val >> 24, ra);
+        break;
+    default:
+        /* Nothing is stored, but protection is checked and the
+           cacheline is marked dirty.  */
+#ifndef CONFIG_USER_ONLY
+        probe_write(env, addr, cpu_mmu_index(env, 0), ra);
+#endif
+        break;
+    }
+}
+
 void HELPER(loaded_fr0)(CPUHPPAState *env)
 {
     uint32_t shadow = env->fr[0] >> 32;