target/riscv: Split pm_enabled into mask and base

Use cached cur_pmmask and cur_pmbase to infer the
current PM mode.

This may decrease the TCG IR by one when pm_enabled
is true and pm_base_enabled is false.

Signed-off-by: LIU Zhiwei <zhiwei_liu@c-sky.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-id: 20220120122050.41546-15-zhiwei_liu@c-sky.com
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>

target/riscv/cpu.h

@@ -448,7 +448,8 @@ FIELD(TB_FLAGS, MSTATUS_HS_VS, 18, 2)
 /* The combination of MXL/SXL/UXL that applies to the current cpu mode. */
 FIELD(TB_FLAGS, XL, 20, 2)
 /* If PointerMasking should be applied */
-FIELD(TB_FLAGS, PM_ENABLED, 22, 1)
+FIELD(TB_FLAGS, PM_MASK_ENABLED, 22, 1)
+FIELD(TB_FLAGS, PM_BASE_ENABLED, 23, 1)
 
 #ifdef TARGET_RISCV32
 #define riscv_cpu_mxl(env)  ((void)(env), MXL_RV32)

target/riscv/cpu_helper.c

@@ -97,27 +97,15 @@ void cpu_get_tb_cpu_state(CPURISCVState *env, target_ulong *pc,
         flags = FIELD_DP32(flags, TB_FLAGS, MSTATUS_HS_VS,
                            get_field(env->mstatus_hs, MSTATUS_VS));
     }
-    if (riscv_has_ext(env, RVJ)) {
-        int priv = flags & TB_FLAGS_PRIV_MMU_MASK;
-        bool pm_enabled = false;
-        switch (priv) {
-        case PRV_U:
-            pm_enabled = env->mmte & U_PM_ENABLE;
-            break;
-        case PRV_S:
-            pm_enabled = env->mmte & S_PM_ENABLE;
-            break;
-        case PRV_M:
-            pm_enabled = env->mmte & M_PM_ENABLE;
-            break;
-        default:
-            g_assert_not_reached();
-        }
-        flags = FIELD_DP32(flags, TB_FLAGS, PM_ENABLED, pm_enabled);
-    }
 #endif
 
     flags = FIELD_DP32(flags, TB_FLAGS, XL, env->xl);
+    if (env->cur_pmmask < (env->xl == MXL_RV32 ? UINT32_MAX : UINT64_MAX)) {
+        flags = FIELD_DP32(flags, TB_FLAGS, PM_MASK_ENABLED, 1);
+    }
+    if (env->cur_pmbase != 0) {
+        flags = FIELD_DP32(flags, TB_FLAGS, PM_BASE_ENABLED, 1);
+    }
 
     *pflags = flags;
 }

target/riscv/translate.c

@@ -108,7 +108,8 @@ typedef struct DisasContext {
     /* Space for 3 operands plus 1 extra for address computation. */
     TCGv temp[4];
     /* PointerMasking extension */
-    bool pm_enabled;
+    bool pm_mask_enabled;
+    bool pm_base_enabled;
 } DisasContext;
 
 static inline bool has_ext(DisasContext *ctx, uint32_t ext)
@@ -397,12 +398,14 @@ static TCGv get_address(DisasContext *ctx, int rs1, int imm)
     TCGv src1 = get_gpr(ctx, rs1, EXT_NONE);
 
     tcg_gen_addi_tl(addr, src1, imm);
-    if (ctx->pm_enabled) {
+    if (ctx->pm_mask_enabled) {
         tcg_gen_and_tl(addr, addr, pm_mask);
-        tcg_gen_or_tl(addr, addr, pm_base);
     } else if (get_xl(ctx) == MXL_RV32) {
         tcg_gen_ext32u_tl(addr, addr);
     }
+    if (ctx->pm_base_enabled) {
+        tcg_gen_or_tl(addr, addr, pm_base);
+    }
     return addr;
 }
 
@@ -925,7 +928,8 @@ static void riscv_tr_init_disas_context(DisasContextBase *dcbase, CPUState *cs)
     ctx->cs = cs;
     ctx->ntemp = 0;
     memset(ctx->temp, 0, sizeof(ctx->temp));
-    ctx->pm_enabled = FIELD_EX32(tb_flags, TB_FLAGS, PM_ENABLED);
+    ctx->pm_mask_enabled = FIELD_EX32(tb_flags, TB_FLAGS, PM_MASK_ENABLED);
+    ctx->pm_base_enabled = FIELD_EX32(tb_flags, TB_FLAGS, PM_BASE_ENABLED);
     ctx->zero = tcg_constant_tl(0);
 }