From: Uros Bizjak <ubizjak@gmail.com>
Date: Thu, 29 Apr 2021 13:24:51 +0000 (+0200)
Subject: i386: Cleanup comparison predicates.
X-Git-Tag: basepoints/gcc-13~8025
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=d03ca8a6148f55e119b8220a9c65147173b32065;p=thirdparty%2Fgcc.git

i386: Cleanup comparison predicates.

CCCmode is allowed only with GEU and LTU comparison codes.  Also allow
CCGZmode for these two codes.  There is no need to check for trivial FP
comparison operator, ix86_fp_compare_code_to_integer will return
UNKNOWN code for unsupported operators.

2021-04-29  Uroš Bizjak  <ubizjak@gmail.com>

gcc/
	* config/i386/predicates.md (fcmov_comparison_operator):
	Do not check for trivial FP comparison operator.
	<case GEU, case LTU>: Allow CCGZmode.
	<case GTU, case LEU>: Do not allow CCCmode.
	(ix86_comparison_operator) <case GTU, case LEU>: Allow only CCmode.
	(ix86_carry_flag_operator): Match only LTU and UNLT code.
	Do not check for trivial FP comparison operator.  Allow CCGZmode.
---

diff --git a/gcc/config/i386/predicates.md b/gcc/config/i386/predicates.md
index b1df8548af63..04a03a70b46c 100644
--- a/gcc/config/i386/predicates.md
+++ b/gcc/config/i386/predicates.md
@@ -1352,16 +1352,17 @@
   enum rtx_code code = GET_CODE (op);
 
   if (inmode == CCFPmode)
-    {
-      if (!ix86_trivial_fp_comparison_operator (op, mode))
-	return false;
-      code = ix86_fp_compare_code_to_integer (code);
-    }
+    code = ix86_fp_compare_code_to_integer (code);
+
   /* i387 supports just limited amount of conditional codes.  */
   switch (code)
     {
-    case LTU: case GTU: case LEU: case GEU:
-      if (inmode == CCmode || inmode == CCFPmode || inmode == CCCmode)
+    case GEU: case LTU:
+      if (inmode == CCCmode || inmode == CCGZmode)
+	return true;
+      /* FALLTHRU */
+    case GTU: case LEU:
+      if (inmode == CCmode || inmode == CCFPmode)
 	return true;
       return false;
     case ORDERED: case UNORDERED:
@@ -1418,11 +1419,11 @@
 	return true;
       return false;
     case GEU: case LTU:
-      if (inmode == CCGZmode)
+      if (inmode == CCCmode || inmode == CCGZmode)
 	return true;
       /* FALLTHRU */
     case GTU: case LEU:
-      if (inmode == CCmode || inmode == CCCmode || inmode == CCGZmode)
+      if (inmode == CCmode)
 	return true;
       return false;
     case ORDERED: case UNORDERED:
@@ -1441,20 +1442,14 @@
 ;; Return true if OP is a valid comparison operator
 ;; testing carry flag to be set.
 (define_predicate "ix86_carry_flag_operator"
-  (match_code "ltu,lt,unlt,gtu,gt,ungt,le,unle,ge,unge,ltgt,uneq")
+  (match_code "ltu,unlt")
 {
   machine_mode inmode = GET_MODE (XEXP (op, 0));
   enum rtx_code code = GET_CODE (op);
 
   if (inmode == CCFPmode)
-    {
-      if (!ix86_trivial_fp_comparison_operator (op, mode))
-	return false;
-      code = ix86_fp_compare_code_to_integer (code);
-    }
-  else if (inmode == CCCmode)
-   return code == LTU || code == GTU;
-  else if (inmode != CCmode)
+    code = ix86_fp_compare_code_to_integer (code);
+  else if (inmode != CCmode && inmode != CCCmode && inmode != CCGZmode)
     return false;
 
   return code == LTU;