target/arm: Introduce pc_curr

Add a new field to retain the address of the instruction currently
being translated.  The 32-bit uses are all within subroutines used
by a32 and t32.  This will become less obvious when t16 support is
merged with a32+t32, and having a clear definition will help.

Convert aarch64 as well for consistency.  Note that there is one
instance of a pre-assert fprintf that used the wrong value for the
address of the current instruction.
Signed-off-by: NRichard Henderson <richard.henderson@linaro.org>
Reviewed-by: NPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: NPhilippe Mathieu-Daudé <philmd@redhat.com>
Message-id: 20190807045335.1361-3-richard.henderson@linaro.org
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

target/arm/translate-a64.c

@@ -1234,7 +1234,7 @@ static inline AArch64DecodeFn *lookup_disas_fn(const AArch64DecodeTable *table,
  */
 static void disas_uncond_b_imm(DisasContext *s, uint32_t insn)
 {
-    uint64_t addr = s->pc + sextract32(insn, 0, 26) * 4 - 4;
+    uint64_t addr = s->pc_curr + sextract32(insn, 0, 26) * 4;
 
     if (insn & (1U << 31)) {
         /* BL Branch with link */
@@ -1262,7 +1262,7 @@ static void disas_comp_b_imm(DisasContext *s, uint32_t insn)
     sf = extract32(insn, 31, 1);
     op = extract32(insn, 24, 1); /* 0: CBZ; 1: CBNZ */
     rt = extract32(insn, 0, 5);
-    addr = s->pc + sextract32(insn, 5, 19) * 4 - 4;
+    addr = s->pc_curr + sextract32(insn, 5, 19) * 4;
 
     tcg_cmp = read_cpu_reg(s, rt, sf);
     label_match = gen_new_label();
@@ -1291,7 +1291,7 @@ static void disas_test_b_imm(DisasContext *s, uint32_t insn)
 
     bit_pos = (extract32(insn, 31, 1) << 5) | extract32(insn, 19, 5);
     op = extract32(insn, 24, 1); /* 0: TBZ; 1: TBNZ */
-    addr = s->pc + sextract32(insn, 5, 14) * 4 - 4;
+    addr = s->pc_curr + sextract32(insn, 5, 14) * 4;
     rt = extract32(insn, 0, 5);
 
     tcg_cmp = tcg_temp_new_i64();
@@ -1322,7 +1322,7 @@ static void disas_cond_b_imm(DisasContext *s, uint32_t insn)
         unallocated_encoding(s);
         return;
     }
-    addr = s->pc + sextract32(insn, 5, 19) * 4 - 4;
+    addr = s->pc_curr + sextract32(insn, 5, 19) * 4;
     cond = extract32(insn, 0, 4);
 
     reset_btype(s);
@@ -1706,7 +1706,7 @@ static void handle_sys(DisasContext *s, uint32_t insn, bool isread,
         TCGv_i32 tcg_syn, tcg_isread;
         uint32_t syndrome;
 
-        gen_a64_set_pc_im(s->pc - 4);
+        gen_a64_set_pc_im(s->pc_curr);
         tmpptr = tcg_const_ptr(ri);
         syndrome = syn_aa64_sysregtrap(op0, op1, op2, crn, crm, rt, isread);
         tcg_syn = tcg_const_i32(syndrome);
@@ -1870,7 +1870,7 @@ 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 - 4);
+            gen_a64_set_pc_im(s->pc_curr);
             gen_helper_pre_hvc(cpu_env);
             gen_ss_advance(s);
             gen_exception_insn(s, 0, EXCP_HVC, syn_aa64_hvc(imm16), 2);
@@ -1880,7 +1880,7 @@ static void disas_exc(DisasContext *s, uint32_t insn)
                 unallocated_encoding(s);
                 break;
             }
-            gen_a64_set_pc_im(s->pc - 4);
+            gen_a64_set_pc_im(s->pc_curr);
             tmp = tcg_const_i32(syn_aa64_smc(imm16));
             gen_helper_pre_smc(cpu_env, tmp);
             tcg_temp_free_i32(tmp);
@@ -2601,7 +2601,7 @@ static void disas_ld_lit(DisasContext *s, uint32_t insn)
 
     tcg_rt = cpu_reg(s, rt);
 
-    clean_addr = tcg_const_i64((s->pc - 4) + imm);
+    clean_addr = tcg_const_i64(s->pc_curr + imm);
     if (is_vector) {
         do_fp_ld(s, rt, clean_addr, size);
     } else {
@@ -3580,7 +3580,7 @@ static void disas_pc_rel_adr(DisasContext *s, uint32_t insn)
     offset = sextract64(insn, 5, 19);
     offset = offset << 2 | extract32(insn, 29, 2);
     rd = extract32(insn, 0, 5);
-    base = s->pc - 4;
+    base = s->pc_curr;
 
     if (page) {
         /* ADRP (page based) */
@@ -11519,7 +11519,7 @@ static void disas_simd_three_reg_same_fp16(DisasContext *s, uint32_t insn)
                 break;
             default:
                 fprintf(stderr, "%s: insn %#04x, fpop %#2x @ %#" PRIx64 "\n",
-                        __func__, insn, fpopcode, s->pc);
+                        __func__, insn, fpopcode, s->pc_curr);
                 g_assert_not_reached();
             }
 
@@ -14030,6 +14030,7 @@ static void disas_a64_insn(CPUARMState *env, DisasContext *s)
 {
     uint32_t insn;
 
+    s->pc_curr = s->pc;
     insn = arm_ldl_code(env, s->pc, s->sctlr_b);
     s->insn = insn;
     s->pc += 4;

target/arm/translate-a64.h

@@ -25,7 +25,7 @@ void unallocated_encoding(DisasContext *s);
         qemu_log_mask(LOG_UNIMP,                                         \
                       "%s:%d: unsupported instruction encoding 0x%08x "  \
                       "at pc=%016" PRIx64 "\n",                          \
-                      __FILE__, __LINE__, insn, s->pc - 4);              \
+                      __FILE__, __LINE__, insn, s->pc_curr);             \
         unallocated_encoding(s);                                         \
     } while (0)
 

target/arm/translate.c

@@ -1197,7 +1197,7 @@ 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 - 4);
+    gen_set_pc_im(s, s->pc_curr);
     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
@@ -1216,7 +1216,7 @@ static inline void gen_smc(DisasContext *s)
      */
     TCGv_i32 tmp;
 
-    gen_set_pc_im(s, s->pc - 4);
+    gen_set_pc_im(s, s->pc_curr);
     tmp = tcg_const_i32(syn_aa32_smc());
     gen_helper_pre_smc(cpu_env, tmp);
     tcg_temp_free_i32(tmp);
@@ -3175,7 +3175,7 @@ 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 - 4);
+    gen_set_pc_im(s, s->pc_curr);
     tcg_reg = load_reg(s, rn);
     tcg_tgtmode = tcg_const_i32(tgtmode);
     tcg_regno = tcg_const_i32(regno);
@@ -3197,7 +3197,7 @@ 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 - 4);
+    gen_set_pc_im(s, s->pc_curr);
     tcg_reg = tcg_temp_new_i32();
     tcg_tgtmode = tcg_const_i32(tgtmode);
     tcg_regno = tcg_const_i32(regno);
@@ -7204,7 +7204,7 @@ static int disas_coproc_insn(DisasContext *s, uint32_t insn)
             }
 
             gen_set_condexec(s);
-            gen_set_pc_im(s, s->pc - 4);
+            gen_set_pc_im(s, s->pc_curr);
             tmpptr = tcg_const_ptr(ri);
             tcg_syn = tcg_const_i32(syndrome);
             tcg_isread = tcg_const_i32(isread);
@@ -7614,7 +7614,7 @@ static void gen_srs(DisasContext *s,
     tmp = tcg_const_i32(mode);
     /* get_r13_banked() will raise an exception if called from System mode */
     gen_set_condexec(s);
-    gen_set_pc_im(s, s->pc - 4);
+    gen_set_pc_im(s, s->pc_curr);
     gen_helper_get_r13_banked(addr, cpu_env, tmp);
     tcg_temp_free_i32(tmp);
     switch (amode) {
@@ -12039,6 +12039,7 @@ static void arm_tr_translate_insn(DisasContextBase *dcbase, CPUState *cpu)
         return;
     }
 
+    dc->pc_curr = dc->pc;
     insn = arm_ldl_code(env, dc->pc, dc->sctlr_b);
     dc->insn = insn;
     dc->pc += 4;
@@ -12107,6 +12108,7 @@ static void thumb_tr_translate_insn(DisasContextBase *dcbase, CPUState *cpu)
         return;
     }
 
+    dc->pc_curr = dc->pc;
     insn = arm_lduw_code(env, dc->pc, dc->sctlr_b);
     is_16bit = thumb_insn_is_16bit(dc, dc->pc, insn);
     dc->pc += 2;

target/arm/translate.h

@@ -11,6 +11,8 @@ typedef struct DisasContext {
     const ARMISARegisters *isar;
 
     target_ulong pc;
+    /* The address of the current instruction being translated. */
+    target_ulong pc_curr;
     target_ulong page_start;
     uint32_t insn;
     /* Nonzero if this instruction has been conditionally skipped.  */