From: Haochen Gui <guihaoc@gcc.gnu.org>
Date: Thu, 9 Jun 2022 05:24:15 +0000 (+0800)
Subject: This patch replaces shift and ior insns with one rotate and mask insn for the split... 
X-Git-Tag: basepoints/gcc-14~6187
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=2fc6e3d55f6080da3a43243f595bd1266595127d;p=thirdparty%2Fgcc.git

This patch replaces shift and ior insns with one rotate and mask insn for the split patterns which are for DI byte swap on Power6.

gcc/
	* config/rs6000/rs6000.md (define_split for bswapdi load): Merge shift
	and ior insns to one rotate and mask insn.
	(define_split for bswapdi register): Likewise.

gcc/testsuite/
	* gcc.target/powerpc/pr93453-1.c: New.
---

diff --git a/gcc/config/rs6000/rs6000.md b/gcc/config/rs6000/rs6000.md
index 3eca448a262..1c125f07e89 100644
--- a/gcc/config/rs6000/rs6000.md
+++ b/gcc/config/rs6000/rs6000.md
@@ -2841,8 +2841,8 @@
       emit_insn (gen_bswapsi2 (dest_32, word2));
     }
 
-  emit_insn (gen_ashldi3 (op3, op3, GEN_INT (32)));
-  emit_insn (gen_iordi3 (dest, dest, op3));
+  emit_insn (gen_rotldi3_insert_3 (dest, op3, GEN_INT (32), dest,
+				   GEN_INT (0xffffffff)));
   DONE;
 })
 
@@ -2927,10 +2927,10 @@
   rtx op3_si  = simplify_gen_subreg (SImode, op3, DImode, lo_off);
 
   emit_insn (gen_lshrdi3 (op2, src, GEN_INT (32)));
-  emit_insn (gen_bswapsi2 (dest_si, src_si));
-  emit_insn (gen_bswapsi2 (op3_si, op2_si));
-  emit_insn (gen_ashldi3 (dest, dest, GEN_INT (32)));
-  emit_insn (gen_iordi3 (dest, dest, op3));
+  emit_insn (gen_bswapsi2 (op3_si, src_si));
+  emit_insn (gen_bswapsi2 (dest_si, op2_si));
+  emit_insn (gen_rotldi3_insert_3 (dest, op3, GEN_INT (32), dest,
+				   GEN_INT (0xffffffff)));
   DONE;
 })
 
diff --git a/gcc/testsuite/gcc.target/powerpc/pr93453-1.c b/gcc/testsuite/gcc.target/powerpc/pr93453-1.c
new file mode 100644
index 00000000000..b396458ba12
--- /dev/null
+++ b/gcc/testsuite/gcc.target/powerpc/pr93453-1.c
@@ -0,0 +1,14 @@
+/* { dg-do compile { target has_arch_ppc64 } } */
+/* { dg-options "-mdejagnu-cpu=power6 -O2" } */
+
+unsigned long load_byte_reverse (unsigned long *in)
+{
+   return __builtin_bswap64 (*in);
+}
+
+unsigned long byte_reverse (unsigned long in)
+{
+   return __builtin_bswap64 (in);
+}
+
+/* { dg-final { scan-assembler-times {\mrldimi\M} 2 } } */