From: Alex Coplan <alex.coplan@arm.com>
Date: Thu, 2 Nov 2023 22:53:44 +0000 (+0000)
Subject: aarch64: Fix up aarch64_print_operand xzr/wzr case
X-Git-Tag: basepoints/gcc-15~3538
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=94415eb7a464e855c37ab01ab300fa5e87e4c4a3;p=thirdparty%2Fgcc.git

aarch64: Fix up aarch64_print_operand xzr/wzr case

This adjusts aarch64_print_operand to recognize zero rtxes in modes other than
VOIDmode.  This allows us to use xzr/wzr for zero vectors, for example.

We extract the test into a helper function, aarch64_const_zero_rtx_p, since this
predicate is needed by later patches.

gcc/ChangeLog:

	* config/aarch64/aarch64-protos.h (aarch64_const_zero_rtx_p): New.
	* config/aarch64/aarch64.cc (aarch64_const_zero_rtx_p): New.
	Use it ...
	(aarch64_print_operand): ... here.  Recognize CONST0_RTXes in
	modes other than VOIDmode.
---

diff --git a/gcc/config/aarch64/aarch64-protos.h b/gcc/config/aarch64/aarch64-protos.h
index 88e59426a04c..8d6ea73bf3fa 100644
--- a/gcc/config/aarch64/aarch64-protos.h
+++ b/gcc/config/aarch64/aarch64-protos.h
@@ -774,6 +774,7 @@ bool aarch64_expand_cpymem (rtx *, bool);
 bool aarch64_expand_setmem (rtx *);
 bool aarch64_float_const_zero_rtx_p (rtx);
 bool aarch64_float_const_rtx_p (rtx);
+bool aarch64_const_zero_rtx_p (rtx);
 bool aarch64_function_arg_regno_p (unsigned);
 bool aarch64_fusion_enabled_p (enum aarch64_fusion_pairs);
 bool aarch64_gen_cpymemqi (rtx *);
diff --git a/gcc/config/aarch64/aarch64.cc b/gcc/config/aarch64/aarch64.cc
index 190608d13810..6d973b3901c7 100644
--- a/gcc/config/aarch64/aarch64.cc
+++ b/gcc/config/aarch64/aarch64.cc
@@ -10851,6 +10851,15 @@ aarch64_float_const_zero_rtx_p (rtx x)
   return real_equal (CONST_DOUBLE_REAL_VALUE (x), &dconst0);
 }
 
+/* Return true if X is any kind of constant zero rtx.  */
+
+bool
+aarch64_const_zero_rtx_p (rtx x)
+{
+  return (x == CONST0_RTX (GET_MODE (x))
+	  || (CONST_DOUBLE_P (x) && aarch64_float_const_zero_rtx_p (x)));
+}
+
 /* Return TRUE if rtx X is immediate constant that fits in a single
    MOVI immediate operation.  */
 bool
@@ -12054,8 +12063,7 @@ aarch64_print_operand (FILE *f, rtx x, int code)
 
     case 'w':
     case 'x':
-      if (x == const0_rtx
-	  || (CONST_DOUBLE_P (x) && aarch64_float_const_zero_rtx_p (x)))
+      if (aarch64_const_zero_rtx_p (x))
 	{
 	  asm_fprintf (f, "%czr", code);
 	  break;