[RFC PATCH 65/66] Hexagon HVX translation

[Taylor Simpson <tsimpson@quicinc.com>]

Changes to packet semantics to support HVX

Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
---
 target/hexagon/translate.c | 174 +++++++++++++++++++++++++++++++++++++++++++++
 target/hexagon/translate.h |  30 ++++++++
 2 files changed, 204 insertions(+)

diff --git a/target/hexagon/translate.c b/target/hexagon/translate.c
index 2fe4dcb..eebe9b4 100644
--- a/target/hexagon/translate.c
+++ b/target/hexagon/translate.c
@@ -51,6 +51,10 @@ TCGv llsc_val;
 TCGv_i64 llsc_val_i64;
 TCGv hex_is_gather_store_insn;
 TCGv hex_gather_issued;
+TCGv hex_VRegs_updated_tmp;
+TCGv hex_VRegs_updated;
+TCGv hex_VRegs_select;
+TCGv hex_QRegs_updated;
 
 static const char * const hexagon_prednames[] = {
   "p0", "p1", "p2", "p3"
@@ -136,6 +140,10 @@ static void gen_start_packet(DisasContext *ctx, packet_t *pkt)
     /* Clear out the disassembly context */
     ctx->ctx_reg_log_idx = 0;
     ctx->ctx_preg_log_idx = 0;
+    ctx->ctx_temp_vregs_idx = 0;
+    ctx->ctx_temp_qregs_idx = 0;
+    ctx->ctx_vreg_log_idx = 0;
+    ctx->ctx_qreg_log_idx = 0;
     for (i = 0; i < STORES_MAX; i++) {
         ctx->ctx_store_width[i] = 0;
     }
@@ -154,6 +162,15 @@ static void gen_start_packet(DisasContext *ctx, packet_t *pkt)
     for (i = 0; i < NUM_PREGS; i++) {
         tcg_gen_movi_tl(hex_pred_written[i], 0);
     }
+
+    if (pkt->pkt_has_hvx) {
+        tcg_gen_movi_tl(hex_VRegs_updated_tmp, 0);
+        tcg_gen_movi_tl(hex_VRegs_updated, 0);
+        tcg_gen_movi_tl(hex_VRegs_select, 0);
+        tcg_gen_movi_tl(hex_QRegs_updated, 0);
+        tcg_gen_movi_tl(hex_is_gather_store_insn, 0);
+        tcg_gen_movi_tl(hex_gather_issued, 0);
+    }
 }
 
 static int is_gather_store_insn(insn_t *insn)
@@ -445,10 +462,149 @@ static bool process_change_of_flow(DisasContext *ctx, packet_t *pkt)
     return false;
 }
 
+void gen_memcpy(TCGv_ptr dest, TCGv_ptr src, size_t n)
+{
+    TCGv_ptr d = tcg_temp_new_ptr();
+    TCGv_ptr s = tcg_temp_new_ptr();
+    int i;
+
+    tcg_gen_addi_ptr(d, dest, 0);
+    tcg_gen_addi_ptr(s, src, 0);
+    if (n % 8 == 0) {
+        TCGv_i64 temp = tcg_temp_new_i64();
+        for (i = 0; i < n / 8; i++) {
+            tcg_gen_ld_i64(temp, s, 0);
+            tcg_gen_st_i64(temp, d, 0);
+            tcg_gen_addi_ptr(s, s, 8);
+            tcg_gen_addi_ptr(d, d, 8);
+        }
+        tcg_temp_free_i64(temp);
+    } else if (n % 4 == 0) {
+        TCGv temp = tcg_temp_new();
+        for (i = 0; i < n / 4; i++) {
+            tcg_gen_ld32u_tl(temp, s, 0);
+            tcg_gen_st32_tl(temp, d, 0);
+            tcg_gen_addi_ptr(s, s, 4);
+            tcg_gen_addi_ptr(d, d, 4);
+        }
+        tcg_temp_free(temp);
+    } else if (n % 2 == 0) {
+        TCGv temp = tcg_temp_new();
+        for (i = 0; i < n / 2; i++) {
+            tcg_gen_ld16u_tl(temp, s, 0);
+            tcg_gen_st16_tl(temp, d, 0);
+            tcg_gen_addi_ptr(s, s, 2);
+            tcg_gen_addi_ptr(d, d, 2);
+        }
+        tcg_temp_free(temp);
+    } else {
+        TCGv temp = tcg_temp_new();
+        for (i = 0; i < n; i++) {
+            tcg_gen_ld8u_tl(temp, s, 0);
+            tcg_gen_st8_tl(temp, d, 0);
+            tcg_gen_addi_ptr(s, s, 1);
+            tcg_gen_addi_ptr(d, d, 1);
+        }
+        tcg_temp_free(temp);
+    }
+
+    tcg_temp_free_ptr(d);
+    tcg_temp_free_ptr(s);
+}
+
+static inline void gen_vec_copy(intptr_t dstoff, intptr_t srcoff, size_t size)
+{
+    TCGv_ptr src = tcg_temp_new_ptr();
+    TCGv_ptr dst = tcg_temp_new_ptr();
+    tcg_gen_addi_ptr(src, cpu_env, srcoff);
+    tcg_gen_addi_ptr(dst, cpu_env, dstoff);
+    gen_memcpy(dst, src, size);
+    tcg_temp_free_ptr(src);
+    tcg_temp_free_ptr(dst);
+}
+
+static void gen_commit_hvx(DisasContext *ctx)
+{
+    int i;
+
+    /*
+     *    for (i = 0; i < ctx->ctx_vreg_log_idx; i++) {
+     *        int rnum = ctx->ctx_vreg_log[i];
+     *        if (ctx->ctx_vreg_is_predicated[i]) {
+     *            if (env->VRegs_updated & (1 << rnum)) {
+     *                env->VRegs[rnum] = env->future_VRegs[rnum];
+     *            }
+     *        } else {
+     *            env->VRegs[rnum] = env->future_VRegs[rnum];
+     *        }
+     *    }
+     */
+    for (i = 0; i < ctx->ctx_vreg_log_idx; i++) {
+        int rnum = ctx->ctx_vreg_log[i];
+        int is_predicated = ctx->ctx_vreg_is_predicated[i];
+        intptr_t dstoff = offsetof(CPUHexagonState, VRegs[rnum]);
+        intptr_t srcoff = offsetof(CPUHexagonState, future_VRegs[rnum]);
+        size_t size = sizeof(mmvector_t);
+
+        if (is_predicated) {
+            TCGv cmp = tcg_temp_local_new();
+            TCGLabel *label_skip = gen_new_label();
+
+            tcg_gen_andi_tl(cmp, hex_VRegs_updated, 1 << rnum);
+            tcg_gen_brcondi_tl(TCG_COND_EQ, cmp, 0, label_skip);
+            {
+                gen_vec_copy(dstoff, srcoff, size);
+            }
+            gen_set_label(label_skip);
+            tcg_temp_free(cmp);
+        } else {
+            gen_vec_copy(dstoff, srcoff, size);
+        }
+    }
+
+    /*
+     *    for (i = 0; i < ctx-_ctx_qreg_log_idx; i++) {
+     *        int rnum = ctx->ctx_qreg_log[i];
+     *        if (ctx->ctx_qreg_is_predicated[i]) {
+     *            if (env->QRegs_updated) & (1 << rnum)) {
+     *                env->QRegs[rnum] = env->future_QRegs[rnum];
+     *            }
+     *        } else {
+     *            env->QRegs[rnum] = env->future_QRegs[rnum];
+     *        }
+     *    }
+     */
+    for (i = 0; i < ctx->ctx_qreg_log_idx; i++) {
+        int rnum = ctx->ctx_qreg_log[i];
+        int is_predicated = ctx->ctx_qreg_is_predicated[i];
+        intptr_t dstoff = offsetof(CPUHexagonState, QRegs[rnum]);
+        intptr_t srcoff = offsetof(CPUHexagonState, future_QRegs[rnum]);
+        size_t size = sizeof(mmqreg_t);
+
+        if (is_predicated) {
+            TCGv cmp = tcg_temp_local_new();
+            TCGLabel *label_skip = gen_new_label();
+
+            tcg_gen_andi_tl(cmp, hex_QRegs_updated, 1 << rnum);
+            tcg_gen_brcondi_tl(TCG_COND_EQ, cmp, 0, label_skip);
+            {
+                gen_vec_copy(dstoff, srcoff, size);
+            }
+            gen_set_label(label_skip);
+            tcg_temp_free(cmp);
+        } else {
+            gen_vec_copy(dstoff, srcoff, size);
+        }
+    }
+
+    gen_helper_commit_hvx_stores(cpu_env);
+}
+
 static void gen_exec_counters(packet_t *pkt)
 {
     int num_insns = pkt->num_insns;
     int num_real_insns = 0;
+    int num_hvx_insns = 0;
     int i;
 
     for (i = 0; i < num_insns; i++) {
@@ -457,6 +613,9 @@ static void gen_exec_counters(packet_t *pkt)
             !GET_ATTRIB(pkt->insn[i].opcode, A_IT_NOP)) {
             num_real_insns++;
         }
+        if (pkt->insn[i].hvx_resource) {
+            num_hvx_insns++;
+        }
     }
 
     tcg_gen_addi_tl(hex_gpr[HEX_REG_QEMU_PKT_CNT],
@@ -465,6 +624,10 @@ static void gen_exec_counters(packet_t *pkt)
         tcg_gen_addi_tl(hex_gpr[HEX_REG_QEMU_INSN_CNT],
                         hex_gpr[HEX_REG_QEMU_INSN_CNT], num_real_insns);
     }
+    if (num_hvx_insns) {
+        tcg_gen_addi_tl(hex_gpr[HEX_REG_QEMU_HVX_CNT],
+                        hex_gpr[HEX_REG_QEMU_HVX_CNT], num_hvx_insns);
+    }
 }
 
 static void gen_commit_packet(DisasContext *ctx, packet_t *pkt)
@@ -476,6 +639,9 @@ static void gen_commit_packet(DisasContext *ctx, packet_t *pkt)
     process_store_log(ctx, pkt);
     process_dczeroa(ctx, pkt);
     end_tb |= process_change_of_flow(ctx, pkt);
+    if (pkt->pkt_has_hvx) {
+        gen_commit_hvx(ctx);
+    }
     gen_exec_counters(pkt);
 #if HEX_DEBUG
     {
@@ -706,6 +872,14 @@ void hexagon_translate_init(void)
         "is_gather_store_insn");
     hex_gather_issued = tcg_global_mem_new(cpu_env,
         offsetof(CPUHexagonState, gather_issued), "gather_issued");
+    hex_VRegs_updated_tmp = tcg_global_mem_new(cpu_env,
+        offsetof(CPUHexagonState, VRegs_updated_tmp), "VRegs_updated_tmp");
+    hex_VRegs_updated = tcg_global_mem_new(cpu_env,
+        offsetof(CPUHexagonState, VRegs_updated), "VRegs_updated");
+    hex_VRegs_select = tcg_global_mem_new(cpu_env,
+        offsetof(CPUHexagonState, VRegs_select), "VRegs_select");
+    hex_QRegs_updated = tcg_global_mem_new(cpu_env,
+        offsetof(CPUHexagonState, QRegs_updated), "QRegs_updated");
     for (i = 0; i < STORES_MAX; i++) {
         sprintf(store_addr_names[i], "store_addr_%d", i);
         hex_store_addr[i] = tcg_global_mem_new(cpu_env,
diff --git a/target/hexagon/translate.h b/target/hexagon/translate.h
index 260ff3c..6bfc376 100644
--- a/target/hexagon/translate.h
+++ b/target/hexagon/translate.h
@@ -32,6 +32,14 @@ typedef struct DisasContext {
     int ctx_preg_log[PRED_WRITES_MAX];
     int ctx_preg_log_idx;
     uint8_t ctx_store_width[STORES_MAX];
+    int ctx_temp_vregs_idx;
+    int ctx_temp_qregs_idx;
+    int ctx_vreg_log[NUM_VREGS];
+    int ctx_vreg_is_predicated[NUM_VREGS];
+    int ctx_vreg_log_idx;
+    int ctx_qreg_log[NUM_QREGS];
+    int ctx_qreg_is_predicated[NUM_QREGS];
+    int ctx_qreg_log_idx;
 } DisasContext;
 
 static inline void ctx_log_reg_write(DisasContext *ctx, int rnum)
@@ -54,6 +62,22 @@ static inline void ctx_log_pred_write(DisasContext *ctx, int pnum)
     ctx->ctx_preg_log_idx++;
 }
 
+static inline void ctx_log_vreg_write(DisasContext *ctx,
+                                      int rnum, int is_predicated)
+{
+    ctx->ctx_vreg_log[ctx->ctx_vreg_log_idx] = rnum;
+    ctx->ctx_vreg_is_predicated[ctx->ctx_vreg_log_idx] = is_predicated;
+    ctx->ctx_vreg_log_idx++;
+}
+
+static inline void ctx_log_qreg_write(DisasContext *ctx,
+                                      int rnum, int is_predicated)
+{
+    ctx->ctx_qreg_log[ctx->ctx_qreg_log_idx] = rnum;
+    ctx->ctx_qreg_is_predicated[ctx->ctx_qreg_log_idx] = is_predicated;
+    ctx->ctx_qreg_log_idx++;
+}
+
 extern TCGv hex_gpr[TOTAL_PER_THREAD_REGS];
 extern TCGv hex_pred[NUM_PREGS];
 extern TCGv hex_next_PC;
@@ -74,9 +98,15 @@ extern TCGv llsc_val;
 extern TCGv_i64 llsc_val_i64;
 extern TCGv hex_is_gather_store_insn;
 extern TCGv hex_gather_issued;
+extern TCGv hex_VRegs_updated_tmp;
+extern TCGv hex_VRegs_updated;
+extern TCGv hex_VRegs_select;
+extern TCGv hex_QRegs_updated;
 
 void hexagon_translate_init(void);
 extern void gen_exception(int excp);
 extern void gen_exception_debug(void);
 
+extern void gen_memcpy(TCGv_ptr dest, TCGv_ptr src, size_t n);
+
 #endif
-- 
2.7.4