From: Jeff Law <jeffreyalaw@gmail.com>
Date: Sun, 16 Oct 2022 16:43:25 +0000 (-0400)
Subject: Add new constraints for upcoming autoinc fixes
X-Git-Tag: basepoints/gcc-14~3889
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=6366e3e8847af98d4728d55951534769d034d02a;p=thirdparty%2Fgcc.git

Add new constraints for upcoming autoinc fixes

GCC does not allow a the operand of an autoinc addressing mode to
overlap with another soure operand in the same insn.  This is primarly
enforced with insn conditions.  However, cases can slip through LRA
and reload.  To address those scenarios we'll take an idea from the
pdp11 port for describing the restriction in constraints as well.

To implement that we need register classes and constraints which are
"all general purpose hardware registers except r0".  And similarly for
r1..r7(sp).

This patch adds those register classes and constraints, but does not
yet use them.

gcc/
	* config/h8300/constraints.md (Z0..Z7): New register
	constraints.
	* config/h8300/h8300.h (reg_class): Add new classes.
	(REG_CLASS_NAMES): Similarly.
	(REG_CLASS_CONTENTS): Similarly.
---

diff --git a/gcc/config/h8300/constraints.md b/gcc/config/h8300/constraints.md
index f71996c5f388..6eaffc169759 100644
--- a/gcc/config/h8300/constraints.md
+++ b/gcc/config/h8300/constraints.md
@@ -216,3 +216,28 @@
   (and (match_test "TARGET_H8300SX")
        (match_code "mem")
        (match_test "CONSTANT_P (XEXP (op, 0))")))
+
+(define_register_constraint "Z0" "NOT_R0_REGS"
+  "@internal")
+
+(define_register_constraint "Z1" "NOT_R1_REGS"
+  "@internal")
+
+(define_register_constraint "Z2" "NOT_R2_REGS"
+  "@internal")
+
+(define_register_constraint "Z3" "NOT_R3_REGS"
+  "@internal")
+
+(define_register_constraint "Z4" "NOT_R4_REGS"
+  "@internal")
+
+(define_register_constraint "Z5" "NOT_R5_REGS"
+  "@internal")
+
+(define_register_constraint "Z6" "NOT_R6_REGS"
+  "@internal")
+
+(define_register_constraint "Z7" "NOT_SP_REGS"
+  "@internal")
+
diff --git a/gcc/config/h8300/h8300.h b/gcc/config/h8300/h8300.h
index 9a6c78cf2d56..45cc4fc77969 100644
--- a/gcc/config/h8300/h8300.h
+++ b/gcc/config/h8300/h8300.h
@@ -282,6 +282,8 @@ extern const char * const *h8_reg_names;
 
 enum reg_class {
   NO_REGS, COUNTER_REGS, SOURCE_REGS, DESTINATION_REGS,
+  NOT_R0_REGS, NOT_R1_REGS, NOT_R2_REGS, NOT_R3_REGS,
+  NOT_R4_REGS, NOT_R5_REGS, NOT_R6_REGS, NOT_SP_REGS,
   GENERAL_REGS, MAC_REGS, ALL_REGS, LIM_REG_CLASSES
 };
 
@@ -291,6 +293,8 @@ enum reg_class {
 
 #define REG_CLASS_NAMES \
 { "NO_REGS", "COUNTER_REGS", "SOURCE_REGS", "DESTINATION_REGS", \
+  "NOT_R0_REGS", "NOT_R1_REGS", "NOT_R2_REGS", "NOT_R3_REGS", \
+  "NOT_R4_REGS", "NOT_R5_REGS", "NOT_R6_REGS", "NOT_SP_REGS", \
   "GENERAL_REGS", "MAC_REGS", "ALL_REGS", "LIM_REGS" }
 
 /* Define which registers fit in which classes.
@@ -302,6 +306,14 @@ enum reg_class {
    {0x010},		/* COUNTER_REGS */	\
    {0x020},		/* SOURCE_REGS */	\
    {0x040},		/* DESTINATION_REGS */	\
+   {0x0fe},		/* NOT_R0_REGS */	\
+   {0x0fd},		/* NOT_R1_REGS */	\
+   {0x0fb},		/* NOT_R2_REGS */	\
+   {0x0f7},		/* NOT_R3_REGS */	\
+   {0x0ef},		/* NOT_R4_REGS */	\
+   {0x0df},		/* NOT_R5_REGS */	\
+   {0x0bf},		/* NOT_R6_REGS */	\
+   {0x07f},		/* NOT_SP_REGS */	\
    {0xeff},		/* GENERAL_REGS */	\
    {0x100},		/* MAC_REGS */		\
    {0xfff},		/* ALL_REGS	*/	\