Hexagon (target/hexagon) Move items to DisasContext

The following items in the CPUHexagonState are only used for bookkeeping
within the translation of a packet.  With recent changes that eliminate
the need to free TCGv variables, these make more sense to be transient
and kept in DisasContext.

The following items are moved
    dczero_addr
    branch_taken
    this_PC

Suggested-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230427230012.3800327-22-tsimpson@quicinc.com>

target/hexagon/README

@@ -304,4 +304,4 @@ Here are some handy places to set breakpoints
         At the start of execution of a packet for a given PC
             br helper_debug_start_packet if env->gpr[41] == 0xdeadbeef
         At the end of execution of a packet for a given PC
-            br helper_debug_commit_end if env->this_PC == 0xdeadbeef
+            br helper_debug_commit_end if this_PC == 0xdeadbeef

target/hexagon/cpu.h

@@ -82,7 +82,6 @@ typedef struct {
 typedef struct CPUArchState {
     target_ulong gpr[TOTAL_PER_THREAD_REGS];
     target_ulong pred[NUM_PREGS];
-    target_ulong branch_taken;
 
     /* For comparing with LLDB on target - see adjust_stack_ptrs function */
     target_ulong last_pc_dumped;
@@ -95,11 +94,9 @@ typedef struct CPUArchState {
      * Only used when HEX_DEBUG is on, but unconditionally included
      * to reduce recompile time when turning HEX_DEBUG on/off.
      */
-    target_ulong this_PC;
     target_ulong reg_written[TOTAL_PER_THREAD_REGS];
 
     MemLog mem_log_stores[STORES_MAX];
-    target_ulong dczero_addr;
 
     float_status fp_status;
 

target/hexagon/genptr.c

@@ -480,9 +480,9 @@ static void gen_write_new_pc_addr(DisasContext *ctx, TCGv addr,
     if (ctx->pkt->pkt_has_multi_cof) {
         /* If there are multiple branches in a packet, ignore the second one */
         tcg_gen_movcond_tl(TCG_COND_NE, hex_gpr[HEX_REG_PC],
-                           hex_branch_taken, tcg_constant_tl(0),
+                           ctx->branch_taken, tcg_constant_tl(0),
                            hex_gpr[HEX_REG_PC], addr);
-        tcg_gen_movi_tl(hex_branch_taken, 1);
+        tcg_gen_movi_tl(ctx->branch_taken, 1);
     } else {
         tcg_gen_mov_tl(hex_gpr[HEX_REG_PC], addr);
     }
@@ -503,7 +503,7 @@ static void gen_write_new_pc_pcrel(DisasContext *ctx, int pc_off,
         ctx->branch_cond = TCG_COND_ALWAYS;
         if (pred != NULL) {
             ctx->branch_cond = cond;
-            tcg_gen_mov_tl(hex_branch_taken, pred);
+            tcg_gen_mov_tl(ctx->branch_taken, pred);
         }
         ctx->branch_dest = dest;
     }

target/hexagon/helper.h

@@ -21,7 +21,7 @@
 DEF_HELPER_FLAGS_2(raise_exception, TCG_CALL_NO_RETURN, noreturn, env, i32)
 DEF_HELPER_1(debug_start_packet, void, env)
 DEF_HELPER_FLAGS_3(debug_check_store_width, TCG_CALL_NO_WG, void, env, int, int)
-DEF_HELPER_FLAGS_4(debug_commit_end, TCG_CALL_NO_WG, void, env, int, int, int)
+DEF_HELPER_FLAGS_5(debug_commit_end, TCG_CALL_NO_WG, void, env, i32, int, int, int)
 DEF_HELPER_2(commit_store, void, env, int)
 DEF_HELPER_3(gather_store, void, env, i32, int)
 DEF_HELPER_1(commit_hvx_stores, void, env)

target/hexagon/macros.h

@@ -648,7 +648,11 @@ static inline TCGv gen_read_ireg(TCGv result, TCGv val, int shift)
                    reg_field_info[FIELD].offset)
 
 #ifdef QEMU_GENERATE
-#define fDCZEROA(REG) tcg_gen_mov_tl(hex_dczero_addr, (REG))
+#define fDCZEROA(REG) \
+    do { \
+        ctx->dczero_addr = tcg_temp_new(); \
+        tcg_gen_mov_tl(ctx->dczero_addr, (REG)); \
+    } while (0)
 #endif
 
 #define fBRANCH_SPECULATE_STALL(DOTNEWVAL, JUMP_COND, SPEC_DIR, HINTBITNUM, \

target/hexagon/op_helper.c

@@ -203,15 +203,14 @@ static void print_store(CPUHexagonState *env, int slot)
 }
 
 /* This function is a handy place to set a breakpoint */
-void HELPER(debug_commit_end)(CPUHexagonState *env,
+void HELPER(debug_commit_end)(CPUHexagonState *env, uint32_t this_PC,
                               int pred_written, int has_st0, int has_st1)
 {
     bool reg_printed = false;
     bool pred_printed = false;
     int i;
 
-    HEX_DEBUG_LOG("Packet committed: pc = 0x" TARGET_FMT_lx "\n",
-                  env->this_PC);
+    HEX_DEBUG_LOG("Packet committed: pc = 0x" TARGET_FMT_lx "\n", this_PC);
     HEX_DEBUG_LOG("slot_cancelled = %d\n", env->slot_cancelled);
 
     for (i = 0; i < TOTAL_PER_THREAD_REGS; i++) {

target/hexagon/translate.c

@@ -41,17 +41,13 @@ static const AnalyzeInsn opcode_analyze[XX_LAST_OPCODE] = {
 
 TCGv hex_gpr[TOTAL_PER_THREAD_REGS];
 TCGv hex_pred[NUM_PREGS];
-TCGv hex_this_PC;
 TCGv hex_slot_cancelled;
-TCGv hex_branch_taken;
 TCGv hex_new_value_usr;
 TCGv hex_reg_written[TOTAL_PER_THREAD_REGS];
 TCGv hex_store_addr[STORES_MAX];
 TCGv hex_store_width[STORES_MAX];
 TCGv hex_store_val32[STORES_MAX];
 TCGv_i64 hex_store_val64[STORES_MAX];
-TCGv hex_pkt_has_store_s1;
-TCGv hex_dczero_addr;
 TCGv hex_llsc_addr;
 TCGv hex_llsc_val;
 TCGv_i64 hex_llsc_val_i64;
@@ -157,7 +153,7 @@ static void gen_end_tb(DisasContext *ctx)
     if (ctx->branch_cond != TCG_COND_NEVER) {
         if (ctx->branch_cond != TCG_COND_ALWAYS) {
             TCGLabel *skip = gen_new_label();
-            tcg_gen_brcondi_tl(ctx->branch_cond, hex_branch_taken, 0, skip);
+            tcg_gen_brcondi_tl(ctx->branch_cond, ctx->branch_taken, 0, skip);
             gen_goto_tb(ctx, 0, ctx->branch_dest, true);
             gen_set_label(skip);
             gen_goto_tb(ctx, 1, ctx->next_PC, false);
@@ -527,16 +523,17 @@ static void gen_start_packet(DisasContext *ctx)
     if (HEX_DEBUG) {
         /* Handy place to set a breakpoint before the packet executes */
         gen_helper_debug_start_packet(cpu_env);
-        tcg_gen_movi_tl(hex_this_PC, ctx->base.pc_next);
     }
 
     /* Initialize the runtime state for packet semantics */
     if (need_slot_cancelled(pkt)) {
         tcg_gen_movi_tl(hex_slot_cancelled, 0);
     }
+    ctx->branch_taken = NULL;
     if (pkt->pkt_has_cof) {
+        ctx->branch_taken = tcg_temp_new();
         if (pkt->pkt_has_multi_cof) {
-            tcg_gen_movi_tl(hex_branch_taken, 0);
+            tcg_gen_movi_tl(ctx->branch_taken, 0);
         }
         if (need_next_PC(ctx)) {
             tcg_gen_movi_tl(hex_gpr[HEX_REG_PC], next_PC);
@@ -815,7 +812,7 @@ static void process_dczeroa(DisasContext *ctx)
         TCGv addr = tcg_temp_new();
         TCGv_i64 zero = tcg_constant_i64(0);
 
-        tcg_gen_andi_tl(addr, hex_dczero_addr, ~0x1f);
+        tcg_gen_andi_tl(addr, ctx->dczero_addr, ~0x1f);
         tcg_gen_qemu_st_i64(zero, addr, ctx->mem_idx, MO_UQ);
         tcg_gen_addi_tl(addr, addr, 8);
         tcg_gen_qemu_st_i64(zero, addr, ctx->mem_idx, MO_UQ);
@@ -1002,8 +999,8 @@ static void gen_commit_packet(DisasContext *ctx)
             tcg_constant_tl(pkt->pkt_has_store_s1 && !pkt->pkt_has_dczeroa);
 
         /* Handy place to set a breakpoint at the end of execution */
-        gen_helper_debug_commit_end(cpu_env, ctx->pred_written,
-                                    has_st0, has_st1);
+        gen_helper_debug_commit_end(cpu_env, tcg_constant_tl(ctx->pkt->pc),
+                                    ctx->pred_written, has_st0, has_st1);
     }
 
     if (pkt->vhist_insn != NULL) {
@@ -1196,14 +1193,8 @@ void hexagon_translate_init(void)
             offsetof(CPUHexagonState, pred[i]),
             hexagon_prednames[i]);
     }
-    hex_this_PC = tcg_global_mem_new(cpu_env,
-        offsetof(CPUHexagonState, this_PC), "this_PC");
     hex_slot_cancelled = tcg_global_mem_new(cpu_env,
         offsetof(CPUHexagonState, slot_cancelled), "slot_cancelled");
-    hex_branch_taken = tcg_global_mem_new(cpu_env,
-        offsetof(CPUHexagonState, branch_taken), "branch_taken");
-    hex_dczero_addr = tcg_global_mem_new(cpu_env,
-        offsetof(CPUHexagonState, dczero_addr), "dczero_addr");
     hex_llsc_addr = tcg_global_mem_new(cpu_env,
         offsetof(CPUHexagonState, llsc_addr), "llsc_addr");
     hex_llsc_val = tcg_global_mem_new(cpu_env,

target/hexagon/translate.h

@@ -71,6 +71,8 @@ typedef struct DisasContext {
     TCGv new_value[TOTAL_PER_THREAD_REGS];
     TCGv new_pred_value[NUM_PREGS];
     TCGv pred_written;
+    TCGv branch_taken;
+    TCGv dczero_addr;
 } DisasContext;
 
 static inline void ctx_log_pred_write(DisasContext *ctx, int pnum)
@@ -189,16 +191,13 @@ static inline void ctx_log_qreg_read(DisasContext *ctx, int qnum)
 
 extern TCGv hex_gpr[TOTAL_PER_THREAD_REGS];
 extern TCGv hex_pred[NUM_PREGS];
-extern TCGv hex_this_PC;
 extern TCGv hex_slot_cancelled;
-extern TCGv hex_branch_taken;
 extern TCGv hex_new_value_usr;
 extern TCGv hex_reg_written[TOTAL_PER_THREAD_REGS];
 extern TCGv hex_store_addr[STORES_MAX];
 extern TCGv hex_store_width[STORES_MAX];
 extern TCGv hex_store_val32[STORES_MAX];
 extern TCGv_i64 hex_store_val64[STORES_MAX];
-extern TCGv hex_dczero_addr;
 extern TCGv hex_llsc_addr;
 extern TCGv hex_llsc_val;
 extern TCGv_i64 hex_llsc_val_i64;