From: Max Filippov <jcmvbkbc@gmail.com>
Date: Wed, 8 Jun 2022 04:01:01 +0000 (-0700)
Subject: gcc: xtensa: fix PR target/105879
X-Git-Tag: basepoints/gcc-14~6192
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=e94c6dbfb57a862dd8a8685eabc4886ad1aaea25;p=thirdparty%2Fgcc.git

gcc: xtensa: fix PR target/105879

split_double operates with the 'word that comes first in memory in the
target' terminology, while gen_lowpart operates with the 'value
representing some low-order bits of X' terminology. They are not
equivalent and must be dealt with differently on little- and big-endian
targets.

gcc/
	PR target/105879
	* config/xtensa/xtensa.md (movdi): Rename 'first' and 'second'
	to 'lowpart' and 'highpart' so that they match 'gen_lowpart' and
	'gen_highpart' bitwise semantics and fix order of highpart and
	lowpart depending on target endianness.
---

diff --git a/gcc/config/xtensa/xtensa.md b/gcc/config/xtensa/xtensa.md
index 6f5cbc541d8..8a119038ba1 100644
--- a/gcc/config/xtensa/xtensa.md
+++ b/gcc/config/xtensa/xtensa.md
@@ -799,11 +799,14 @@
 	 because of offering further optimization opportunities.  */
       if (register_operand (operands[0], DImode))
 	{
-	  rtx first, second;
-
-	  split_double (operands[1], &first, &second);
-	  emit_insn (gen_movsi (gen_lowpart (SImode, operands[0]), first));
-	  emit_insn (gen_movsi (gen_highpart (SImode, operands[0]), second));
+	  rtx lowpart, highpart;
+
+	  if (TARGET_BIG_ENDIAN)
+	    split_double (operands[1], &highpart, &lowpart);
+	  else
+	    split_double (operands[1], &lowpart, &highpart);
+	  emit_insn (gen_movsi (gen_lowpart (SImode, operands[0]), lowpart));
+	  emit_insn (gen_movsi (gen_highpart (SImode, operands[0]), highpart));
 	  DONE;
 	}