From a23305afc0a5d4f166fb54a5be202c651d214d70 Mon Sep 17 00:00:00 2001
From: Denis Drakhnya <numas13@gmail.com>
Date: Sun, 15 Nov 2020 18:39:30 +0200
Subject: [PATCH] target: e2k: Add pcs_{push,pop}.

---
 target/e2k/cpu.h    | 35 +++++++++++++++++++++-
 target/e2k/helper.c | 71 ++++++++++++++++++++++++++++++---------------
 2 files changed, 82 insertions(+), 24 deletions(-)

diff --git a/target/e2k/cpu.h b/target/e2k/cpu.h
index 17af5f7749..26b009d3dd 100644
--- a/target/e2k/cpu.h
+++ b/target/e2k/cpu.h
@@ -17,7 +17,7 @@ void e2k_tcg_initialize(void);
 #define SET_FIELD(v, f, s, l) \
     ( \
         ((v) & ~GEN_MASK_LEN((s), (l))) | \
-        ((((typeof(v)) (f)) << (s)) & GEN_MASK_LEN((s), (l))) \
+        ((((typeof((v))) (f)) << (s)) & GEN_MASK_LEN((s), (l))) \
     )
 
 #define MMU_USER_IDX 1
@@ -229,6 +229,39 @@ int e2k_cpu_signal_handler(int host_signum, void *pinfo, void *puc);
 
 #define cpu_signal_handler e2k_cpu_signal_handler
 
+static inline target_ulong e2k_state_pcs_base_get(CPUE2KState *env)
+{
+    return GET_FIELD(env->pcsp_lo, PCSP_LO_BASE_OFF, PCSP_LO_BASE_END);
+}
+
+static inline void e2k_state_pcs_base_set(CPUE2KState *env, target_ulong pcsp)
+{
+    env->pcsp_lo = SET_FIELD(env->pcsp_lo, pcsp, PCSP_LO_BASE_OFF,
+        PCSP_LO_BASE_LEN);
+}
+
+static inline size_t e2k_state_pcs_index_get(CPUE2KState *env)
+{
+    return GET_FIELD(env->pcsp_hi, PCSP_HI_IND_OFF, PCSP_HI_IND_END);
+}
+
+static inline void e2k_state_pcs_index_set(CPUE2KState *env, size_t ind)
+{
+    env->pcsp_hi = SET_FIELD(env->pcsp_hi, ind, PCSP_HI_IND_OFF,
+        PCSP_HI_IND_LEN);
+}
+
+static inline size_t e2k_state_pcs_size_get(CPUE2KState *env)
+{
+    return GET_FIELD(env->pcsp_hi, PCSP_HI_SIZE_OFF, PCSP_HI_SIZE_END);
+}
+
+static inline void e2k_state_pcs_size_set(CPUE2KState *env, size_t size)
+{
+    env->pcsp_hi = SET_FIELD(env->pcsp_hi, size, PCSP_HI_SIZE_OFF,
+        PCSP_HI_SIZE_LEN);
+}
+
 static inline int e2k_state_wbs_get(CPUE2KState *env)
 {
     return GET_FIELD(env->cr1_lo, CR1_LO_WBS_OFF, CR1_LO_WBS_END);
diff --git a/target/e2k/helper.c b/target/e2k/helper.c
index 1dd8266112..7b5635e39f 100644
--- a/target/e2k/helper.c
+++ b/target/e2k/helper.c
@@ -14,48 +14,73 @@ void helper_raise_exception(CPUE2KState *env, int tt)
     cpu_loop_exit(cs);
 }
 
+static void pcs_push(CPUE2KState *env)
+{
+    size_t size = e2k_state_pcs_size_get(env);
+    size_t offset = e2k_state_pcs_index_get(env);
+    uint64_t *pcsp = (uint64_t *) (e2k_state_pcs_base_get(env) + offset);
+
+    if (offset + 32 > size) {
+        /* TODO: allocate more memory */
+        abort();
+    }
+
+    memcpy(pcsp, &env->pf, 8);
+    memcpy(pcsp + 1, &env->nip, 8);
+    memcpy(pcsp + 2, &env->cr1_lo, 8);
+    memcpy(pcsp + 3, &env->cr1_hi, 8);
+
+    e2k_state_pcs_index_set(env, offset + 32);
+}
+
+static void pcs_pop(CPUE2KState *env)
+{
+    size_t offset = e2k_state_pcs_index_get(env);
+    uint64_t *pcsp = (uint64_t *) (e2k_state_pcs_base_get(env) + offset - 32);
+
+    if (offset < 32) {
+        /* TODO: SIGKILL */
+        abort();
+    }
+
+    memcpy(&env->pf, pcsp, 8);
+    memcpy(&env->ip, pcsp + 1, 8);
+    memcpy(&env->cr1_lo, pcsp + 2, 8);
+    memcpy(&env->cr1_hi, pcsp + 3, 8);
+
+    e2k_state_pcs_index_set(env, offset - 32);
+}
+
 static inline void do_call(CPUE2KState *env, target_ulong ctpr)
 {
-    unsigned int offset, wbs, wsz, new_wbs, new_wsz;
-    uint64_t *pcsp = (uint64_t *)
-        GET_FIELD(env->pcsp_lo, PCSP_LO_BASE_OFF, PCSP_LO_BASE_END);
+    int wbs, wsz, new_wbs, new_wsz;
 
     wbs = e2k_state_wbs_get(env);
     wsz = e2k_state_wsz_get(env);
     new_wbs = (wbs + env->call_wbs) % WREGS_SIZE;
     new_wsz = wsz - env->call_wbs;
 
-    /* save procedure chain */
-    offset = (env->pcsp_hi & GEN_MASK(0, 31)) / 8;
-    pcsp[offset + 0] = env->pf;
-    pcsp[offset + 1] = env->nip;
-    pcsp[offset + 2] = env->cr1_lo;
-    pcsp[offset + 3] = env->cr1_hi;
-    /* TODO: check stack overflow */
-    env->pcsp_hi = env->pcsp_hi + 32;
+    if (wsz < 0) {
+        /* TODO: SIGSEGV */
+        abort();
+    }
+
+    /* save procedure chain info */
+    pcs_push(env);
 
-    /* TODO: check if call_wbs is less or equal then wsz */
     e2k_state_wbs_set(env, new_wbs);
     e2k_state_wsz_set(env, new_wsz);
-    /* TODO: check rbs/rsz after call */
+
     env->ip = GET_FIELD(ctpr, CTPR_BASE_OFF, CTPR_BASE_END);
 }
 
 static void do_return(CPUE2KState *env)
 {
-    unsigned int offset = env->pcsp_hi & GEN_MASK(0, 31);
-    uint64_t *pcsp = (uint64_t *) (GET_FIELD(env->pcsp_lo, PCSP_LO_BASE_OFF,
-        PCSP_LO_BASE_END) + offset - 32);
 //    uint64_t *psp = (uint64_t *) GET_FIELD(env->psp_lo, PSP_LO_BASE_OFF,
 //        PSP_LO_BASE_END);
 
-    env->pf = pcsp[0];
-    env->ip = pcsp[1];
-    env->nip = env->ip + 8;
-    env->cr1_lo = pcsp[2];
-    env->cr1_hi = pcsp[3];
-    /* TODO: check stack overflow */
-    env->pcsp_hi = env->pcsp_hi - 32;
+    /* restore procedure chain info */
+    pcs_pop(env);
 
     // TODO: restore regs
 }