target/arm: Change gen_*set_pc_im to gen_*update_pc

In preparation for TARGET_TB_PCREL, reduce reliance on
absolute values by passing in pc difference.

Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20221020030641.2066807-4-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

5 files changed, 56 insertions, 54 deletions

diff --git a/target/arm/translate-a32.h b/target/arm/translate-a32.h
index 78a84c1..5339c22 100644
--- a/target/arm/translate-a32.h
+++ b/target/arm/translate-a32.h
@@ -40,7 +40,7 @@ void write_neon_element64(TCGv_i64 src, int reg, int ele, MemOp memop);
 TCGv_i32 add_reg_for_lit(DisasContext *s, int reg, int ofs);
 void gen_set_cpsr(TCGv_i32 var, uint32_t mask);
 void gen_set_condexec(DisasContext *s);
-void gen_set_pc_im(DisasContext *s, target_ulong val);
+void gen_update_pc(DisasContext *s, target_long diff);
 void gen_lookup_tb(DisasContext *s);
 long vfp_reg_offset(bool dp, unsigned reg);
 long neon_full_reg_offset(unsigned reg);
diff --git a/target/arm/translate-a64.c b/target/arm/translate-a64.c
index 928445a..b638d14 100644
--- a/target/arm/translate-a64.c
+++ b/target/arm/translate-a64.c
@@ -140,9 +140,9 @@ static void reset_btype(DisasContext *s)
     }
 }
 
-void gen_a64_set_pc_im(uint64_t val)
+void gen_a64_update_pc(DisasContext *s, target_long diff)
 {
-    tcg_gen_movi_i64(cpu_pc, val);
+    tcg_gen_movi_i64(cpu_pc, s->pc_curr + diff);
 }
 
 /*
@@ -334,14 +334,14 @@ static void gen_exception_internal(int excp)
 
 static void gen_exception_internal_insn(DisasContext *s, uint64_t pc, int excp)
 {
-    gen_a64_set_pc_im(pc);
+    gen_a64_update_pc(s, pc - s->pc_curr);
     gen_exception_internal(excp);
     s->base.is_jmp = DISAS_NORETURN;
 }
 
 static void gen_exception_bkpt_insn(DisasContext *s, uint32_t syndrome)
 {
-    gen_a64_set_pc_im(s->pc_curr);
+    gen_a64_update_pc(s, 0);
     gen_helper_exception_bkpt_insn(cpu_env, tcg_constant_i32(syndrome));
     s->base.is_jmp = DISAS_NORETURN;
 }
@@ -376,11 +376,11 @@ static void gen_goto_tb(DisasContext *s, int n, int64_t diff)
 
     if (use_goto_tb(s, dest)) {
         tcg_gen_goto_tb(n);
-        gen_a64_set_pc_im(dest);
+        gen_a64_update_pc(s, diff);
         tcg_gen_exit_tb(s->base.tb, n);
         s->base.is_jmp = DISAS_NORETURN;
     } else {
-        gen_a64_set_pc_im(dest);
+        gen_a64_update_pc(s, diff);
         if (s->ss_active) {
             gen_step_complete_exception(s);
         } else {
@@ -1952,7 +1952,7 @@ static void handle_sys(DisasContext *s, uint32_t insn, bool isread,
         uint32_t syndrome;
 
         syndrome = syn_aa64_sysregtrap(op0, op1, op2, crn, crm, rt, isread);
-        gen_a64_set_pc_im(s->pc_curr);
+        gen_a64_update_pc(s, 0);
         gen_helper_access_check_cp_reg(cpu_env,
                                        tcg_constant_ptr(ri),
                                        tcg_constant_i32(syndrome),
@@ -1962,7 +1962,7 @@ static void handle_sys(DisasContext *s, uint32_t insn, bool isread,
          * The readfn or writefn might raise an exception;
          * synchronize the CPU state in case it does.
          */
-        gen_a64_set_pc_im(s->pc_curr);
+        gen_a64_update_pc(s, 0);
     }
 
     /* Handle special cases first */
@@ -2172,7 +2172,7 @@ static void disas_exc(DisasContext *s, uint32_t insn)
             /* The pre HVC helper handles cases when HVC gets trapped
              * as an undefined insn by runtime configuration.
              */
-            gen_a64_set_pc_im(s->pc_curr);
+            gen_a64_update_pc(s, 0);
             gen_helper_pre_hvc(cpu_env);
             gen_ss_advance(s);
             gen_exception_insn_el(s, s->base.pc_next, EXCP_HVC,
@@ -2183,7 +2183,7 @@ static void disas_exc(DisasContext *s, uint32_t insn)
                 unallocated_encoding(s);
                 break;
             }
-            gen_a64_set_pc_im(s->pc_curr);
+            gen_a64_update_pc(s, 0);
             gen_helper_pre_smc(cpu_env, tcg_constant_i32(syn_aa64_smc(imm16)));
             gen_ss_advance(s);
             gen_exception_insn_el(s, s->base.pc_next, EXCP_SMC,
@@ -14935,7 +14935,7 @@ static void aarch64_tr_tb_stop(DisasContextBase *dcbase, CPUState *cpu)
          */
         switch (dc->base.is_jmp) {
         default:
-            gen_a64_set_pc_im(dc->base.pc_next);
+            gen_a64_update_pc(dc, 4);
             /* fall through */
         case DISAS_EXIT:
         case DISAS_JUMP:
@@ -14952,13 +14952,13 @@ static void aarch64_tr_tb_stop(DisasContextBase *dcbase, CPUState *cpu)
             break;
         default:
         case DISAS_UPDATE_EXIT:
-            gen_a64_set_pc_im(dc->base.pc_next);
+            gen_a64_update_pc(dc, 4);
             /* fall through */
         case DISAS_EXIT:
             tcg_gen_exit_tb(NULL, 0);
             break;
         case DISAS_UPDATE_NOCHAIN:
-            gen_a64_set_pc_im(dc->base.pc_next);
+            gen_a64_update_pc(dc, 4);
             /* fall through */
         case DISAS_JUMP:
             tcg_gen_lookup_and_goto_ptr();
@@ -14967,11 +14967,11 @@ static void aarch64_tr_tb_stop(DisasContextBase *dcbase, CPUState *cpu)
         case DISAS_SWI:
             break;
         case DISAS_WFE:
-            gen_a64_set_pc_im(dc->base.pc_next);
+            gen_a64_update_pc(dc, 4);
             gen_helper_wfe(cpu_env);
             break;
         case DISAS_YIELD:
-            gen_a64_set_pc_im(dc->base.pc_next);
+            gen_a64_update_pc(dc, 4);
             gen_helper_yield(cpu_env);
             break;
         case DISAS_WFI:
@@ -14979,7 +14979,7 @@ static void aarch64_tr_tb_stop(DisasContextBase *dcbase, CPUState *cpu)
              * This is a special case because we don't want to just halt
              * the CPU if trying to debug across a WFI.
              */
-            gen_a64_set_pc_im(dc->base.pc_next);
+            gen_a64_update_pc(dc, 4);
             gen_helper_wfi(cpu_env, tcg_constant_i32(4));
             /*
              * The helper doesn't necessarily throw an exception, but we
diff --git a/target/arm/translate-vfp.c b/target/arm/translate-vfp.c
index 94cc1e4..070f465 100644
--- a/target/arm/translate-vfp.c
+++ b/target/arm/translate-vfp.c
@@ -856,7 +856,7 @@ static bool trans_VMSR_VMRS(DisasContext *s, arg_VMSR_VMRS *a)
         case ARM_VFP_FPSID:
             if (s->current_el == 1) {
                 gen_set_condexec(s);
-                gen_set_pc_im(s, s->pc_curr);
+                gen_update_pc(s, 0);
                 gen_helper_check_hcr_el2_trap(cpu_env,
                                               tcg_constant_i32(a->rt),
                                               tcg_constant_i32(a->reg));
diff --git a/target/arm/translate.c b/target/arm/translate.c
index ae30c26..9863a08 100644
--- a/target/arm/translate.c
+++ b/target/arm/translate.c
@@ -768,9 +768,9 @@ void gen_set_condexec(DisasContext *s)
     }
 }
 
-void gen_set_pc_im(DisasContext *s, target_ulong val)
+void gen_update_pc(DisasContext *s, target_long diff)
 {
-    tcg_gen_movi_i32(cpu_R[15], val);
+    tcg_gen_movi_i32(cpu_R[15], s->pc_curr + diff);
 }
 
 /* Set PC and Thumb state from var.  var is marked as dead.  */
@@ -862,7 +862,7 @@ static inline void gen_bxns(DisasContext *s, int rm)
 
     /* The bxns helper may raise an EXCEPTION_EXIT exception, so in theory
      * we need to sync state before calling it, but:
-     *  - we don't need to do gen_set_pc_im() because the bxns helper will
+     *  - we don't need to do gen_update_pc() because the bxns helper will
      *    always set the PC itself
      *  - we don't need to do gen_set_condexec() because BXNS is UNPREDICTABLE
      *    unless it's outside an IT block or the last insn in an IT block,
@@ -883,7 +883,7 @@ static inline void gen_blxns(DisasContext *s, int rm)
      * We do however need to set the PC, because the blxns helper reads it.
      * The blxns helper may throw an exception.
      */
-    gen_set_pc_im(s, s->base.pc_next);
+    gen_update_pc(s, curr_insn_len(s));
     gen_helper_v7m_blxns(cpu_env, var);
     tcg_temp_free_i32(var);
     s->base.is_jmp = DISAS_EXIT;
@@ -1051,7 +1051,7 @@ static inline void gen_hvc(DisasContext *s, int imm16)
      * as an undefined insn by runtime configuration (ie before
      * the insn really executes).
      */
-    gen_set_pc_im(s, s->pc_curr);
+    gen_update_pc(s, 0);
     gen_helper_pre_hvc(cpu_env);
     /* Otherwise we will treat this as a real exception which
      * happens after execution of the insn. (The distinction matters
@@ -1059,7 +1059,7 @@ static inline void gen_hvc(DisasContext *s, int imm16)
      * for single stepping.)
      */
     s->svc_imm = imm16;
-    gen_set_pc_im(s, s->base.pc_next);
+    gen_update_pc(s, curr_insn_len(s));
     s->base.is_jmp = DISAS_HVC;
 }
 
@@ -1068,16 +1068,16 @@ static inline void gen_smc(DisasContext *s)
     /* As with HVC, we may take an exception either before or after
      * the insn executes.
      */
-    gen_set_pc_im(s, s->pc_curr);
+    gen_update_pc(s, 0);
     gen_helper_pre_smc(cpu_env, tcg_constant_i32(syn_aa32_smc()));
-    gen_set_pc_im(s, s->base.pc_next);
+    gen_update_pc(s, curr_insn_len(s));
     s->base.is_jmp = DISAS_SMC;
 }
 
 static void gen_exception_internal_insn(DisasContext *s, uint32_t pc, int excp)
 {
     gen_set_condexec(s);
-    gen_set_pc_im(s, pc);
+    gen_update_pc(s, pc - s->pc_curr);
     gen_exception_internal(excp);
     s->base.is_jmp = DISAS_NORETURN;
 }
@@ -1103,10 +1103,10 @@ static void gen_exception_insn_el_v(DisasContext *s, uint64_t pc, int excp,
                                     uint32_t syn, TCGv_i32 tcg_el)
 {
     if (s->aarch64) {
-        gen_a64_set_pc_im(pc);
+        gen_a64_update_pc(s, pc - s->pc_curr);
     } else {
         gen_set_condexec(s);
-        gen_set_pc_im(s, pc);
+        gen_update_pc(s, pc - s->pc_curr);
     }
     gen_exception_el_v(excp, syn, tcg_el);
     s->base.is_jmp = DISAS_NORETURN;
@@ -1121,10 +1121,10 @@ void gen_exception_insn_el(DisasContext *s, uint64_t pc, int excp,
 void gen_exception_insn(DisasContext *s, uint64_t pc, int excp, uint32_t syn)
 {
     if (s->aarch64) {
-        gen_a64_set_pc_im(pc);
+        gen_a64_update_pc(s, pc - s->pc_curr);
     } else {
         gen_set_condexec(s);
-        gen_set_pc_im(s, pc);
+        gen_update_pc(s, pc - s->pc_curr);
     }
     gen_exception(excp, syn);
     s->base.is_jmp = DISAS_NORETURN;
@@ -1133,7 +1133,7 @@ void gen_exception_insn(DisasContext *s, uint64_t pc, int excp, uint32_t syn)
 static void gen_exception_bkpt_insn(DisasContext *s, uint32_t syn)
 {
     gen_set_condexec(s);
-    gen_set_pc_im(s, s->pc_curr);
+    gen_update_pc(s, 0);
     gen_helper_exception_bkpt_insn(cpu_env, tcg_constant_i32(syn));
     s->base.is_jmp = DISAS_NORETURN;
 }
@@ -2596,10 +2596,10 @@ static void gen_goto_tb(DisasContext *s, int n, int diff)
 
     if (translator_use_goto_tb(&s->base, dest)) {
         tcg_gen_goto_tb(n);
-        gen_set_pc_im(s, dest);
+        gen_update_pc(s, diff);
         tcg_gen_exit_tb(s->base.tb, n);
     } else {
-        gen_set_pc_im(s, dest);
+        gen_update_pc(s, diff);
         gen_goto_ptr();
     }
     s->base.is_jmp = DISAS_NORETURN;
@@ -2608,9 +2608,11 @@ static void gen_goto_tb(DisasContext *s, int n, int diff)
 /* Jump, specifying which TB number to use if we gen_goto_tb() */
 static inline void gen_jmp_tb(DisasContext *s, uint32_t dest, int tbno)
 {
+    int diff = dest - s->pc_curr;
+
     if (unlikely(s->ss_active)) {
         /* An indirect jump so that we still trigger the debug exception.  */
-        gen_set_pc_im(s, dest);
+        gen_update_pc(s, diff);
         s->base.is_jmp = DISAS_JUMP;
         return;
     }
@@ -2627,7 +2629,7 @@ static inline void gen_jmp_tb(DisasContext *s, uint32_t dest, int tbno)
          *    gen_jmp();
          * on the second call to gen_jmp().
          */
-        gen_goto_tb(s, tbno, dest - s->pc_curr);
+        gen_goto_tb(s, tbno, diff);
         break;
     case DISAS_UPDATE_NOCHAIN:
     case DISAS_UPDATE_EXIT:
@@ -2636,7 +2638,7 @@ static inline void gen_jmp_tb(DisasContext *s, uint32_t dest, int tbno)
          * Avoid using goto_tb so we really do exit back to the main loop
          * and don't chain to another TB.
          */
-        gen_set_pc_im(s, dest);
+        gen_update_pc(s, diff);
         gen_goto_ptr();
         s->base.is_jmp = DISAS_NORETURN;
         break;
@@ -2904,7 +2906,7 @@ static void gen_msr_banked(DisasContext *s, int r, int sysm, int rn)
 
     /* Sync state because msr_banked() can raise exceptions */
     gen_set_condexec(s);
-    gen_set_pc_im(s, s->pc_curr);
+    gen_update_pc(s, 0);
     tcg_reg = load_reg(s, rn);
     gen_helper_msr_banked(cpu_env, tcg_reg,
                           tcg_constant_i32(tgtmode),
@@ -2924,7 +2926,7 @@ static void gen_mrs_banked(DisasContext *s, int r, int sysm, int rn)
 
     /* Sync state because mrs_banked() can raise exceptions */
     gen_set_condexec(s);
-    gen_set_pc_im(s, s->pc_curr);
+    gen_update_pc(s, 0);
     tcg_reg = tcg_temp_new_i32();
     gen_helper_mrs_banked(tcg_reg, cpu_env,
                           tcg_constant_i32(tgtmode),
@@ -4745,7 +4747,7 @@ static void do_coproc_insn(DisasContext *s, int cpnum, int is64,
             }
 
             gen_set_condexec(s);
-            gen_set_pc_im(s, s->pc_curr);
+            gen_update_pc(s, 0);
             gen_helper_access_check_cp_reg(cpu_env,
                                            tcg_constant_ptr(ri),
                                            tcg_constant_i32(syndrome),
@@ -4756,7 +4758,7 @@ static void do_coproc_insn(DisasContext *s, int cpnum, int is64,
              * synchronize the CPU state in case it does.
              */
             gen_set_condexec(s);
-            gen_set_pc_im(s, s->pc_curr);
+            gen_update_pc(s, 0);
         }
 
         /* Handle special cases first */
@@ -4770,7 +4772,7 @@ static void do_coproc_insn(DisasContext *s, int cpnum, int is64,
                 unallocated_encoding(s);
                 return;
             }
-            gen_set_pc_im(s, s->base.pc_next);
+            gen_update_pc(s, curr_insn_len(s));
             s->base.is_jmp = DISAS_WFI;
             return;
         default:
@@ -5157,7 +5159,7 @@ static void gen_srs(DisasContext *s,
     addr = tcg_temp_new_i32();
     /* get_r13_banked() will raise an exception if called from System mode */
     gen_set_condexec(s);
-    gen_set_pc_im(s, s->pc_curr);
+    gen_update_pc(s, 0);
     gen_helper_get_r13_banked(addr, cpu_env, tcg_constant_i32(mode));
     switch (amode) {
     case 0: /* DA */
@@ -6226,7 +6228,7 @@ static bool trans_YIELD(DisasContext *s, arg_YIELD *a)
      * scheduling of other vCPUs.
      */
     if (!(tb_cflags(s->base.tb) & CF_PARALLEL)) {
-        gen_set_pc_im(s, s->base.pc_next);
+        gen_update_pc(s, curr_insn_len(s));
         s->base.is_jmp = DISAS_YIELD;
     }
     return true;
@@ -6242,7 +6244,7 @@ static bool trans_WFE(DisasContext *s, arg_WFE *a)
      * implemented so we can't sleep like WFI does.
      */
     if (!(tb_cflags(s->base.tb) & CF_PARALLEL)) {
-        gen_set_pc_im(s, s->base.pc_next);
+        gen_update_pc(s, curr_insn_len(s));
         s->base.is_jmp = DISAS_WFE;
     }
     return true;
@@ -6251,7 +6253,7 @@ static bool trans_WFE(DisasContext *s, arg_WFE *a)
 static bool trans_WFI(DisasContext *s, arg_WFI *a)
 {
     /* For WFI, halt the vCPU until an IRQ. */
-    gen_set_pc_im(s, s->base.pc_next);
+    gen_update_pc(s, curr_insn_len(s));
     s->base.is_jmp = DISAS_WFI;
     return true;
 }
@@ -8761,7 +8763,7 @@ static bool trans_SVC(DisasContext *s, arg_SVC *a)
         (a->imm == semihost_imm)) {
         gen_exception_internal_insn(s, s->pc_curr, EXCP_SEMIHOST);
     } else {
-        gen_set_pc_im(s, s->base.pc_next);
+        gen_update_pc(s, curr_insn_len(s));
         s->svc_imm = a->imm;
         s->base.is_jmp = DISAS_SWI;
     }
@@ -9774,7 +9776,7 @@ static void arm_tr_tb_stop(DisasContextBase *dcbase, CPUState *cpu)
         case DISAS_TOO_MANY:
         case DISAS_UPDATE_EXIT:
         case DISAS_UPDATE_NOCHAIN:
-            gen_set_pc_im(dc, dc->base.pc_next);
+            gen_update_pc(dc, curr_insn_len(dc));
             /* fall through */
         default:
             /* FIXME: Single stepping a WFI insn will not halt the CPU. */
@@ -9798,13 +9800,13 @@ static void arm_tr_tb_stop(DisasContextBase *dcbase, CPUState *cpu)
             gen_goto_tb(dc, 1, curr_insn_len(dc));
             break;
         case DISAS_UPDATE_NOCHAIN:
-            gen_set_pc_im(dc, dc->base.pc_next);
+            gen_update_pc(dc, curr_insn_len(dc));
             /* fall through */
         case DISAS_JUMP:
             gen_goto_ptr();
             break;
         case DISAS_UPDATE_EXIT:
-            gen_set_pc_im(dc, dc->base.pc_next);
+            gen_update_pc(dc, curr_insn_len(dc));
             /* fall through */
         default:
             /* indicate that the hash table must be used to find the next TB */
@@ -9844,7 +9846,7 @@ static void arm_tr_tb_stop(DisasContextBase *dcbase, CPUState *cpu)
         gen_set_label(dc->condlabel);
         gen_set_condexec(dc);
         if (unlikely(dc->ss_active)) {
-            gen_set_pc_im(dc, dc->base.pc_next);
+            gen_update_pc(dc, curr_insn_len(dc));
             gen_singlestep_exception(dc);
         } else {
             gen_goto_tb(dc, 1, curr_insn_len(dc));
diff --git a/target/arm/translate.h b/target/arm/translate.h
index 90bf7c5..d651044 100644
--- a/target/arm/translate.h
+++ b/target/arm/translate.h
@@ -254,7 +254,7 @@ static inline int curr_insn_len(DisasContext *s)
  * For instructions which want an immediate exit to the main loop, as opposed
  * to attempting to use lookup_and_goto_ptr.  Unlike DISAS_UPDATE_EXIT, this
  * doesn't write the PC on exiting the translation loop so you need to ensure
- * something (gen_a64_set_pc_im or runtime helper) has done so before we reach
+ * something (gen_a64_update_pc or runtime helper) has done so before we reach
  * return from cpu_tb_exec.
  */
 #define DISAS_EXIT      DISAS_TARGET_9
@@ -263,14 +263,14 @@ static inline int curr_insn_len(DisasContext *s)
 
 #ifdef TARGET_AARCH64
 void a64_translate_init(void);
-void gen_a64_set_pc_im(uint64_t val);
+void gen_a64_update_pc(DisasContext *s, target_long diff);
 extern const TranslatorOps aarch64_translator_ops;
 #else
 static inline void a64_translate_init(void)
 {
 }
 
-static inline void gen_a64_set_pc_im(uint64_t val)
+static inline void gen_a64_update_pc(DisasContext *s, target_long diff)
 {
 }
 #endif