[committed] Fix a couple constraints on the H8 in preparation for LRA conversion

[committed] Fix a couple constraints on the H8 in preparation for LRA conversion

[Jeff Law]

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So this is the 2nd patch on the way to LRA for the H8.

LRA is more sensitive to getting define_constraint vs 
define_memory_constraint vs define_special_memory_constraint correct. 
than reload.

The H8 port has the "Q" constraint, which is used to indicate memory 
addresses that can be used under certain circumstances in various ALU 
operations.  So it should be a memory constraint.  Ideally it'd would be 
a simple memory constraint, but it's used in contexts where MEMs are 
valid only for certain parts in the H8 family.  So it really needs to be 
a special_memory_constraint.

The "Zz" constraint accepts memory, but the forms are limited and can 
not be reloaded into a register.   It seems to be working, but I 
wouldn't be totally surprised if this got stressed in the right way if 
it broke.

Anyway, this patch fixes "Q" and "Zz" to be special memory constraints.

Regression tested with gdbsim and pushed to the trunk.

jeff

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commit 02d79fb228c9f4c7d00dfe09b6ca7ef1392afbec
Author: Jeff Law <jlaw@ventanamicro>
Date:   Wed May 10 05:25:12 2023 -0600

    Fix a couple constraints on the H8 in preparation for LRA conversion
    
    So this is the 2nd patch on the way to LRA for the H8.
    
    LRA is more sensitive to getting define_constraint vs define_memory_constraint
    vs define_special_memory_constraint correct.  than reload.
    
    The H8 port has the "Q" constraint, which is used to indicate memory addresses
    that can be used under certain circumstances in various ALU operations.  So it
    should be a memory constraint.  Ideally it'd would be a simple memory
    constraint, but it's used in contexts where MEMs are valid only for certain
    parts in the H8 family.  So it really needs to be a special_memory_constraint.
    
    The "Zz" constraint accepts memory, but the forms are limited and can not be
    reloaded into a register.   It seems to be working, but I wouldn't be totally
    surprised if this got stressed in the right way if it broke.
    
    Anyway, this patch fixes "Q" and "Zz" to be special memory constraints.
    
    Regression tested with gdbsim and pushed to the trunk.
    
    gcc
            * config/h8300/constraints.md (Q): Make this a special memory
            constraint.
            (Zz): Similarly.

diff --git a/gcc/config/h8300/constraints.md b/gcc/config/h8300/constraints.md
index f1ebce14dad..3aef1205fef 100644
--- a/gcc/config/h8300/constraints.md
+++ b/gcc/config/h8300/constraints.md
@@ -144,7 +144,7 @@ (define_constraint "G"
        (match_test "op == CONST0_RTX (SFmode)")))
 
 ;; Extra constraints.
-(define_constraint "Q"
+(define_special_memory_constraint "Q"
   "@internal"
   (and (match_test "TARGET_H8300SX")
        (match_operand 0 "memory_operand")))
@@ -211,7 +211,7 @@ (define_constraint "Y2"
   (and (match_code "const_int")
        (match_test "exact_log2 (ival & 0xff) != -1")))
 
-(define_constraint "Zz"
+(define_special_memory_constraint "Zz"
   "@internal"
   (and (match_test "TARGET_H8300SX")
        (match_code "mem")