From: Andreas Krebbel <krebbel@linux.ibm.com>
Date: Tue, 5 Feb 2019 17:19:26 +0000 (+0000)
Subject: S/390: Remove load and test fp splitter
X-Git-Tag: releases/gcc-7.5.0~612
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=617eb3a96c4140e24a87acb983c74ccbb0971147;p=thirdparty%2Fgcc.git

S/390: Remove load and test fp splitter

gcc/ChangeLog:

2019-02-05  Andreas Krebbel  <krebbel@linux.ibm.com>

	Backport from mainline
	2019-02-05  Andreas Krebbel  <krebbel@linux.ibm.com>

	PR target/88856
	* config/s390/s390.md: Remove load and test FP splitter.

From-SVN: r268552
---

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 016f146f397f..7c8da3e7ca11 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,11 @@
+2019-02-05  Andreas Krebbel  <krebbel@linux.ibm.com>
+
+	Backport from mainline
+	2019-02-05  Andreas Krebbel  <krebbel@linux.ibm.com>
+
+	PR target/88856
+	* config/s390/s390.md: Remove load and test FP splitter.
+
 2019-02-04  Bill Schmidt  <wshmidt@linux.ibm.com>
 
 	PR target/87064
diff --git a/gcc/config/s390/s390.md b/gcc/config/s390/s390.md
index 6560ded06934..bb3993548550 100644
--- a/gcc/config/s390/s390.md
+++ b/gcc/config/s390/s390.md
@@ -1332,10 +1332,11 @@
 ; (TF|DF|SF|TD|DD|SD) instructions
 
 
-; load and test instructions turn SNaN into QNaN what is not
+; FIXME: load and test instructions turn SNaN into QNaN what is not
 ; acceptable if the target will be used afterwards.  On the other hand
 ; they are quite convenient for implementing comparisons with 0.0. So
-; try to enable them via splitter if the value isn't needed anymore.
+; try to enable them via splitter/peephole if the value isn't needed anymore.
+; See testcases: load-and-test-fp-1.c and load-and-test-fp-2.c
 
 ; ltxbr, ltdbr, ltebr, ltxtr, ltdtr
 (define_insn "*cmp<mode>_ccs_0"
@@ -1348,22 +1349,6 @@
    [(set_attr "op_type" "RRE")
     (set_attr "type"  "fsimp<mode>")])
 
-(define_split
-  [(set (match_operand 0 "cc_reg_operand")
-	(compare (match_operand:FP 1 "register_operand")
-		 (match_operand:FP 2 "const0_operand")))]
-  "TARGET_HARD_FLOAT && REG_P (operands[1]) && dead_or_set_p (insn, operands[1])"
-  [(parallel
-    [(set (match_dup 0) (match_dup 3))
-     (clobber (match_dup 1))])]
- {
-   /* s390_match_ccmode requires the compare to have the same CC mode
-      as the CC destination register.  */
-   operands[3] = gen_rtx_COMPARE (GET_MODE (operands[0]),
-				  operands[1], operands[2]);
- })
-
-
 ; VX: TFmode in FPR pairs: use cxbr instead of wfcxb
 ; cxtr, cdtr, cxbr, cdbr, cebr, cdb, ceb, wfcsb, wfcdb
 (define_insn "*cmp<mode>_ccs"