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Diffstat (limited to 'target/riscv/translate.c')
-rw-r--r--target/riscv/translate.c99
1 files changed, 65 insertions, 34 deletions
diff --git a/target/riscv/translate.c b/target/riscv/translate.c
index 933b11c50d..8a33da811e 100644
--- a/target/riscv/translate.c
+++ b/target/riscv/translate.c
@@ -59,8 +59,8 @@ typedef enum {
 
 typedef struct DisasContext {
     DisasContextBase base;
-    /* pc_succ_insn points to the instruction following base.pc_next */
-    target_ulong pc_succ_insn;
+    target_ulong cur_insn_len;
+    target_ulong pc_save;
     target_ulong priv_ver;
     RISCVMXL misa_mxl_max;
     RISCVMXL xl;
@@ -224,26 +224,34 @@ static void decode_save_opc(DisasContext *ctx)
     ctx->insn_start = NULL;
 }
 
-static void gen_set_pc_imm(DisasContext *ctx, target_ulong dest)
+static void gen_pc_plus_diff(TCGv target, DisasContext *ctx,
+                             target_long diff)
 {
-    if (get_xl(ctx) == MXL_RV32) {
-        dest = (int32_t)dest;
+    target_ulong dest = ctx->base.pc_next + diff;
+
+    assert(ctx->pc_save != -1);
+    if (tb_cflags(ctx->base.tb) & CF_PCREL) {
+        tcg_gen_addi_tl(target, cpu_pc, dest - ctx->pc_save);
+        if (get_xl(ctx) == MXL_RV32) {
+            tcg_gen_ext32s_tl(target, target);
+        }
+    } else {
+        if (get_xl(ctx) == MXL_RV32) {
+            dest = (int32_t)dest;
+        }
+        tcg_gen_movi_tl(target, dest);
     }
-    tcg_gen_movi_tl(cpu_pc, dest);
 }
 
-static void gen_set_pc(DisasContext *ctx, TCGv dest)
+static void gen_update_pc(DisasContext *ctx, target_long diff)
 {
-    if (get_xl(ctx) == MXL_RV32) {
-        tcg_gen_ext32s_tl(cpu_pc, dest);
-    } else {
-        tcg_gen_mov_tl(cpu_pc, dest);
-    }
+    gen_pc_plus_diff(cpu_pc, ctx, diff);
+    ctx->pc_save = ctx->base.pc_next + diff;
 }
 
 static void generate_exception(DisasContext *ctx, int excp)
 {
-    gen_set_pc_imm(ctx, ctx->base.pc_next);
+    gen_update_pc(ctx, 0);
     gen_helper_raise_exception(cpu_env, tcg_constant_i32(excp));
     ctx->base.is_jmp = DISAS_NORETURN;
 }
@@ -259,9 +267,9 @@ static void gen_exception_illegal(DisasContext *ctx)
     }
 }
 
-static void gen_exception_inst_addr_mis(DisasContext *ctx)
+static void gen_exception_inst_addr_mis(DisasContext *ctx, TCGv target)
 {
-    tcg_gen_st_tl(cpu_pc, cpu_env, offsetof(CPURISCVState, badaddr));
+    tcg_gen_st_tl(target, cpu_env, offsetof(CPURISCVState, badaddr));
     generate_exception(ctx, RISCV_EXCP_INST_ADDR_MIS);
 }
 
@@ -285,18 +293,33 @@ static void exit_tb(DisasContext *ctx)
     tcg_gen_exit_tb(NULL, 0);
 }
 
-static void gen_goto_tb(DisasContext *ctx, int n, target_ulong dest)
+static void gen_goto_tb(DisasContext *ctx, int n, target_long diff)
 {
+    target_ulong dest = ctx->base.pc_next + diff;
+
      /*
       * Under itrigger, instruction executes one by one like singlestep,
       * direct block chain benefits will be small.
       */
     if (translator_use_goto_tb(&ctx->base, dest) && !ctx->itrigger) {
-        tcg_gen_goto_tb(n);
-        gen_set_pc_imm(ctx, dest);
+        /*
+         * For pcrel, the pc must always be up-to-date on entry to
+         * the linked TB, so that it can use simple additions for all
+         * further adjustments.  For !pcrel, the linked TB is compiled
+         * to know its full virtual address, so we can delay the
+         * update to pc to the unlinked path.  A long chain of links
+         * can thus avoid many updates to the PC.
+         */
+        if (tb_cflags(ctx->base.tb) & CF_PCREL) {
+            gen_update_pc(ctx, diff);
+            tcg_gen_goto_tb(n);
+        } else {
+            tcg_gen_goto_tb(n);
+            gen_update_pc(ctx, diff);
+        }
         tcg_gen_exit_tb(ctx->base.tb, n);
     } else {
-        gen_set_pc_imm(ctx, dest);
+        gen_update_pc(ctx, diff);
         lookup_and_goto_ptr(ctx);
     }
 }
@@ -547,19 +570,22 @@ static void gen_set_fpr_d(DisasContext *ctx, int reg_num, TCGv_i64 t)
 
 static void gen_jal(DisasContext *ctx, int rd, target_ulong imm)
 {
-    target_ulong next_pc;
+    TCGv succ_pc = dest_gpr(ctx, rd);
 
     /* check misaligned: */
-    next_pc = ctx->base.pc_next + imm;
-    if (!ctx->cfg_ptr->ext_zca) {
-        if ((next_pc & 0x3) != 0) {
-            gen_exception_inst_addr_mis(ctx);
+    if (!has_ext(ctx, RVC) && !ctx->cfg_ptr->ext_zca) {
+        if ((imm & 0x3) != 0) {
+            TCGv target_pc = tcg_temp_new();
+            gen_pc_plus_diff(target_pc, ctx, imm);
+            gen_exception_inst_addr_mis(ctx, target_pc);
             return;
         }
     }
 
-    gen_set_gpri(ctx, rd, ctx->pc_succ_insn);
-    gen_goto_tb(ctx, 0, ctx->base.pc_next + imm); /* must use this for safety */
+    gen_pc_plus_diff(succ_pc, ctx, ctx->cur_insn_len);
+    gen_set_gpr(ctx, rd, succ_pc);
+
+    gen_goto_tb(ctx, 0, imm); /* must use this for safety */
     ctx->base.is_jmp = DISAS_NORETURN;
 }
 
@@ -1117,15 +1143,16 @@ static void decode_opc(CPURISCVState *env, DisasContext *ctx, uint16_t opcode)
     };
 
     ctx->virt_inst_excp = false;
+    ctx->cur_insn_len = insn_len(opcode);
     /* Check for compressed insn */
-    if (insn_len(opcode) == 2) {
+    if (ctx->cur_insn_len == 2) {
         ctx->opcode = opcode;
-        ctx->pc_succ_insn = ctx->base.pc_next + 2;
         /*
          * The Zca extension is added as way to refer to instructions in the C
          * extension that do not include the floating-point loads and stores
          */
-        if (ctx->cfg_ptr->ext_zca && decode_insn16(ctx, opcode)) {
+        if ((has_ext(ctx, RVC) || ctx->cfg_ptr->ext_zca) &&
+            decode_insn16(ctx, opcode)) {
             return;
         }
     } else {
@@ -1134,7 +1161,6 @@ static void decode_opc(CPURISCVState *env, DisasContext *ctx, uint16_t opcode)
                              translator_lduw(env, &ctx->base,
                                              ctx->base.pc_next + 2));
         ctx->opcode = opcode32;
-        ctx->pc_succ_insn = ctx->base.pc_next + 4;
 
         for (size_t i = 0; i < ARRAY_SIZE(decoders); ++i) {
             if (decoders[i].guard_func(ctx) &&
@@ -1154,7 +1180,7 @@ static void riscv_tr_init_disas_context(DisasContextBase *dcbase, CPUState *cs)
     RISCVCPU *cpu = RISCV_CPU(cs);
     uint32_t tb_flags = ctx->base.tb->flags;
 
-    ctx->pc_succ_insn = ctx->base.pc_first;
+    ctx->pc_save = ctx->base.pc_first;
     ctx->priv = FIELD_EX32(tb_flags, TB_FLAGS, PRIV);
     ctx->mem_idx = FIELD_EX32(tb_flags, TB_FLAGS, MEM_IDX);
     ctx->mstatus_fs = FIELD_EX32(tb_flags, TB_FLAGS, FS);
@@ -1189,8 +1215,13 @@ static void riscv_tr_tb_start(DisasContextBase *db, CPUState *cpu)
 static void riscv_tr_insn_start(DisasContextBase *dcbase, CPUState *cpu)
 {
     DisasContext *ctx = container_of(dcbase, DisasContext, base);
+    target_ulong pc_next = ctx->base.pc_next;
+
+    if (tb_cflags(dcbase->tb) & CF_PCREL) {
+        pc_next &= ~TARGET_PAGE_MASK;
+    }
 
-    tcg_gen_insn_start(ctx->base.pc_next, 0);
+    tcg_gen_insn_start(pc_next, 0);
     ctx->insn_start = tcg_last_op();
 }
 
@@ -1202,7 +1233,7 @@ static void riscv_tr_translate_insn(DisasContextBase *dcbase, CPUState *cpu)
 
     ctx->ol = ctx->xl;
     decode_opc(env, ctx, opcode16);
-    ctx->base.pc_next = ctx->pc_succ_insn;
+    ctx->base.pc_next += ctx->cur_insn_len;
 
     /* Only the first insn within a TB is allowed to cross a page boundary. */
     if (ctx->base.is_jmp == DISAS_NEXT) {
@@ -1229,7 +1260,7 @@ static void riscv_tr_tb_stop(DisasContextBase *dcbase, CPUState *cpu)
 
     switch (ctx->base.is_jmp) {
     case DISAS_TOO_MANY:
-        gen_goto_tb(ctx, 0, ctx->base.pc_next);
+        gen_goto_tb(ctx, 0, 0);
         break;
     case DISAS_NORETURN:
         break;