tic4x: sign extension using shifts

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tic4x: sign extension using shifts

Alan Modra-3
Don't do that.  Especially don't use shift counts that assume the type
being shifted is 32 bits when the type is long/unsigned long.  Also
reverts part of a change I made on 2019-12-11 to tic4x_print_register
that on closer inspection turns out to be unnecessary.

include/
        * opcode/tic4x.h (EXTR): Delete.
        (EXTRU, EXTRS, INSERTU, INSERTS): Rewrite without zero/sign
        extension using shifts.  Do trim INSERTU value to specified bitfield.
opcodes/
        * tic4x-dis.c (tic4x_print_register): Remove dead code.
gas/
        * config/tc-tic4x.c (tic4x_operands_match): Correct tic3x trap
        insertion.

diff --git a/gas/config/tc-tic4x.c b/gas/config/tc-tic4x.c
index 913120d9ab..cc477b62bb 100644
--- a/gas/config/tc-tic4x.c
+++ b/gas/config/tc-tic4x.c
@@ -2193,7 +2193,7 @@ tic4x_operands_match (tic4x_inst_t *inst, tic4x_insn_t *tinsn, int check)
  }
       else if (exp->X_add_number < 32 && IS_CPU_TIC3X (tic4x_cpu))
  {
-  INSERTU (opcode, exp->X_add_number | 0x20, 4, 0);
+  INSERTU (opcode, exp->X_add_number | 0x20, 5, 0);
   continue;
  }
       else
diff --git a/include/opcode/tic4x.h b/include/opcode/tic4x.h
index 66b4ebfd08..04e3f0853d 100644
--- a/include/opcode/tic4x.h
+++ b/include/opcode/tic4x.h
@@ -23,11 +23,13 @@
 #define IS_CPU_TIC4X(v) ((v) ==  0 || (v) == 40 || (v) == 44)
 
 /* Define some bitfield extraction/insertion macros.  */
-#define EXTR(inst, m, l)          ((inst) << (31 - (m)) >> (31 - ((m) - (l))))
-#define EXTRU(inst, m, l)         EXTR ((unsigned long)(inst), (m), (l))
-#define EXTRS(inst, m, l)         EXTR ((long)(inst), (m), (l))
-#define INSERTU(inst, val, m, l)  (inst |= ((val) << (l)))
-#define INSERTS(inst, val, m, l)  INSERTU (inst, ((val) & ((1 << ((m) - (l) + 1)) - 1)), m, l)
+#define EXTRU(inst, m, l) \
+  (((inst) >> (l)) & ((2u << ((m) - (l))) - 1))
+#define EXTRS(inst, m, l) \
+  ((int) ((EXTRU (inst, m, l) ^ (1u << ((m) - (l)))) - (1u << ((m) - (l)))))
+#define INSERTU(inst, val, m, l) \
+  ((inst) |= ((val) & ((2u << ((m) - (l))) - 1)) << (l))
+#define INSERTS INSERTU
 
 /* Define register numbers.  */
 typedef enum
diff --git a/opcodes/tic4x-dis.c b/opcodes/tic4x-dis.c
index 1d7946918b..34e270b713 100644
--- a/opcodes/tic4x-dis.c
+++ b/opcodes/tic4x-dis.c
@@ -148,8 +148,7 @@ tic4x_print_register (struct disassemble_info *info, unsigned long regno)
       = (tic4x_register_t *)(tic4x_registers + i);
  }
     }
-  if (regno > (IS_CPU_TIC4X (tic4x_version) ? TIC4X_REG_MAX : TIC3X_REG_MAX)
-      || registertable[regno] == NULL)
+  if (regno > (IS_CPU_TIC4X (tic4x_version) ? TIC4X_REG_MAX : TIC3X_REG_MAX))
     return 0;
   if (info != NULL)
     (*info->fprintf_func) (info->stream, "%s", registertable[regno]->name);

--
Alan Modra
Australia Development Lab, IBM