Re: [committed] More infrastructure to avoid bogus RTL on H8

[Jeff Law via Gcc-patches]

On 10/25/22 13:59, Jan-Benedict Glaw wrote:

Hi Jeff!

On Mon, 2022-10-17 17:47:16 -0600, Jeff Law via Gcc-patches 
<gcc-patches@gcc.gnu.org> wrote:

--- a/gcc/config/h8300/h8300.cc
+++ b/gcc/config/h8300/h8300.cc
@@ -5531,6 +5531,32 @@ h8300_ok_for_sibcall_p (tree fndecl, tree)

return 1;

  }
+
+/* Return TRUE if OP is a PRE_INC or PRE_DEC
+   instruction using REG, FALSE otherwise.  */
+
+bool
+pre_incdec_with_reg (rtx op, int reg)
+{
+  /* OP must be a MEM.  */
+  if (GET_CODE (op) != MEM)
+    return false;
+
+  /* The address must be a PRE_INC or PRE_DEC.  */
+  op = XEXP (op, 0);
+  if (GET_CODE (op) != PRE_DEC && GET_CODE (op) != PRE_INC)
+    return false;
+
+  /* It must be a register that is being incremented
+     or decremented.  */
+  op = XEXP (op, 0);
+  if (!REG_P (op))
+    return false;
+
+  /* Finally, check that the register number matches.  */
+  return REGNO (op) == reg;

This results in a new signed-vs-unsigned warning for me:

[all 2022-10-25 00:41:11] ../../gcc/gcc/config/h8300/h8300.cc: In function 
'bool pre_incdec_with_reg(rtx, int)':
[all 2022-10-25 00:41:11] ../../gcc/gcc/config/h8300/h8300.cc:5557:21: error: 
comparison of integer expressions of different signedness: 'unsigned int' and 
'int' [-Werror=sign-compare]
[all 2022-10-25 00:41:11]  5557 |   return REGNO (op) == reg;

Fixed via the attached patch.  Thanks for pointing it out.


jeff


commit 724d3f926b94672de960dbe88fb699bbdd7fde97
Author: Jeff Law <jeffreya...@gmail.com>
Date:   Fri Oct 28 23:33:06 2022 -0400

    Fix signed vs unsigned issue in H8 port
    
    gcc/
            * config/h8300/h8300.cc (pre_incdec_with_reg): Make reg argument
            an unsigned int
            * config/h8300/h8300-protos.h (pre_incdec_with_reg): Adjust 
prototype.

diff --git a/gcc/config/h8300/h8300-protos.h b/gcc/config/h8300/h8300-protos.h
index 8c989495c29..77adfaba07b 100644
--- a/gcc/config/h8300/h8300-protos.h
+++ b/gcc/config/h8300/h8300-protos.h
@@ -100,7 +100,7 @@ extern int h8300_initial_elimination_offset (int, int);
 extern int h8300_regs_ok_for_stm (int, rtx[]);
 extern int h8300_hard_regno_rename_ok (unsigned int, unsigned int);
 extern bool h8300_move_ok (rtx, rtx);
-extern bool pre_incdec_with_reg (rtx, int);
+extern bool pre_incdec_with_reg (rtx, unsigned int);
 
 struct cpp_reader;
 extern void h8300_pr_interrupt (struct cpp_reader *);
diff --git a/gcc/config/h8300/h8300.cc b/gcc/config/h8300/h8300.cc
index ce0702edecb..cd7975e2fff 100644
--- a/gcc/config/h8300/h8300.cc
+++ b/gcc/config/h8300/h8300.cc
@@ -5536,7 +5536,7 @@ h8300_ok_for_sibcall_p (tree fndecl, tree)
    instruction using REG, FALSE otherwise.  */
 
 bool
-pre_incdec_with_reg (rtx op, int reg)
+pre_incdec_with_reg (rtx op, unsigned int reg)
 {
   /* OP must be a MEM.  */
   if (GET_CODE (op) != MEM)