i386: Optimize _mm_storeu_si16 w/o SSE4 [PR105079]

Optimize _mm_storeu_si16 to use MOVD from a SSE to an integer register
instead of PEXTRW from a low word of the SSE register to an integer reg.

Avoid the transformation when optimizing for size for targets without
TARGET_INTER_UNIT_MOVES_FROM_VEC capability, where the transformation
results in two moves via a memory location.

2022-05-03  Uroš Bizjak  <ubizjak@gmail.com>

gcc/ChangeLog:

	PR target/105079
	* config/i386/sse.md (*vec_extract<mode>_0_mem): New pre-reload
	define_insn_and_split pattern.

gcc/testsuite/ChangeLog:

	PR target/105079
	* gcc.target/i386/pr105079.c: New test.
	* gcc.target/i386/pr95483-1.c (dg-options): Use -msse4.1.

diff --git a/gcc/config/i386/sse.md b/gcc/config/i386/sse.md
index 5e93aa23b47a40dee70872bea958c0d3a9e5f25d..7b791def54285b021b61eaee3632395cec5473e2 100644 (file)
--- a/gcc/config/i386/sse.md
+++ b/gcc/config/i386/sse.md
@@ -19021,6 +19021,26 @@
 (define_mode_iterator PEXTR_MODE12
   [(V16QI "TARGET_SSE4_1") V8HI])
 
+(define_insn_and_split "*vec_extract<mode>_0_mem"
+  [(set (match_operand:<ssescalarmode> 0 "memory_operand")
+       (vec_select:<ssescalarmode>
+         (match_operand:PEXTR_MODE12 1 "register_operand")
+         (parallel [(const_int 0)])))]
+  "TARGET_SSE2
+   && !TARGET_SSE4_1
+   && (TARGET_INTER_UNIT_MOVES_FROM_VEC
+       || optimize_function_for_speed_p (cfun))
+   && ix86_pre_reload_split ()"
+  "#"
+  "&& 1"
+  [(set (match_dup 2) (match_dup 3))
+   (set (match_dup 0) (match_dup 4))]
+{
+  operands[2] = gen_reg_rtx (SImode);
+  operands[3] = gen_lowpart (SImode, force_reg (<MODE>mode, operands[1]));
+  operands[4] = gen_lowpart (<ssescalarmode>mode, operands[2]);
+})
+
 (define_insn "*vec_extract<mode>"
   [(set (match_operand:<ssescalarmode> 0 "register_sse4nonimm_operand" "=r,m")
        (vec_select:<ssescalarmode>

diff --git a/gcc/testsuite/gcc.target/i386/pr105079.c b/gcc/testsuite/gcc.target/i386/pr105079.c
new file mode 100644 (file)
index 0000000..4ecf864
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/pr105079.c
@@ -0,0 +1,11 @@
+/* PR target/105079 */
+/* { dg-do compile } */
+/* { dg-options "-O2 -msse2 -mno-sse4.1" } */
+/* { dg-final { scan-assembler-not "pextrw" } } */
+
+#include <xmmintrin.h>
+
+void store16 (void *p, __m128i v)
+{
+  _mm_storeu_si16 (p, v);
+}

diff --git a/gcc/testsuite/gcc.target/i386/pr95483-1.c b/gcc/testsuite/gcc.target/i386/pr95483-1.c
index 0f3e0bf928093a5e178cbc77bfc3aec6c6f0b668..26b2e8275eba157d0d783428fc4adf1158b55318 100644 (file)
--- a/gcc/testsuite/gcc.target/i386/pr95483-1.c
+++ b/gcc/testsuite/gcc.target/i386/pr95483-1.c
@@ -1,5 +1,5 @@
 /* { dg-do compile } */
-/* { dg-options "-O2 -msse2" } */
+/* { dg-options "-O2 -msse4.1" } */
 /* { dg-final { scan-assembler-times "pxor\[ \\t\]+\[^\n\]*%xmm\[0-9\]+\[^\n\]*%xmm\[0-9\]+(?:\n|\[ \\t\]+#)" 1 } } */
 /* { dg-final { scan-assembler-times "pinsrw\[ \\t\]+\[^\n\]*%xmm\[0-9\]+(?:\n|\[ \\t\]+#)" 1 } } */
 /* { dg-final { scan-assembler-times "pextrw\[ \\t\]+\[^\n\]*%xmm\[0-9\]+\[^\n\]*(?:\n|\[ \\t\]+#)" 1 } } */