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* [PATCH] i386: Fix up *_doubleword_mask [PR105825]
@ 2022-06-03 10:17 Jakub Jelinek
  2022-06-03 10:23 ` Uros Bizjak
  0 siblings, 1 reply; 4+ messages in thread
From: Jakub Jelinek @ 2022-06-03 10:17 UTC (permalink / raw)
  To: Uros Bizjak; +Cc: gcc-patches

Hi!

My PR105778 patch apparently broke the following testcase.
If the mask has the top relevant bit clear (i.e. we know we are shifting
by 0 to wordsize bits - 1) but doesn't have all the bits below it set,
we emit andsi3 before the shift sequence.  When the pattern had :SI
for that operand, that was just fine, but now that it can be also HImode
or for -m64 DImode, we either can use a lowpart or paradoxical subreg to
SImode as the following patch, or we could use a HImode or DImode AND.

Ok for trunk if it passes bootstrap/regtest on x86_64-linux and i686-linux?

2022-06-03  Jakub Jelinek  <jakub@redhat.com>

	PR target/105825
	* config/i386/i386.md (*ashl<dwi>3_doubleword_mask,
	*<insn><dwi>3_doubleword_mask): If top bit of mask is clear, but lower
	bits of mask aren't all set and operands[2] doesn't have SImode,
	force it to get and use subreg to SImode for andsi3 operand.

	* gcc.dg/pr105825.c: New test.

--- gcc/config/i386/i386.md.jj	2022-06-02 10:40:00.034660893 +0200
+++ gcc/config/i386/i386.md	2022-06-03 12:00:39.323292767 +0200
@@ -11935,6 +11935,11 @@ (define_insn_and_split "*ashl<dwi>3_doub
       != ((<MODE_SIZE> * BITS_PER_UNIT) - 1))
     {
       rtx tem = gen_reg_rtx (SImode);
+      if (GET_MODE (operands[2]) != SImode)
+	{
+	  operands[2] = force_reg (GET_MODE (operands[2]), operands[2]);
+	  operands[2] = gen_lowpart (SImode, operands[2]);
+	}
       emit_insn (gen_andsi3 (tem, operands[2], operands[3]));
       operands[2] = tem;
     }
@@ -12900,6 +12905,11 @@ (define_insn_and_split "*<insn><dwi>3_do
       != ((<MODE_SIZE> * BITS_PER_UNIT) - 1))
     {
       rtx tem = gen_reg_rtx (SImode);
+      if (GET_MODE (operands[2]) != SImode)
+	{
+	  operands[2] = force_reg (GET_MODE (operands[2]), operands[2]);
+	  operands[2] = gen_lowpart (SImode, operands[2]);
+	}
       emit_insn (gen_andsi3 (tem, operands[2], operands[3]));
       operands[2] = tem;
     }
--- gcc/testsuite/gcc.dg/pr105825.c.jj	2022-06-03 12:01:58.008460659 +0200
+++ gcc/testsuite/gcc.dg/pr105825.c	2022-06-03 12:01:41.259637783 +0200
@@ -0,0 +1,13 @@
+/* PR target/105825 */
+/* { dg-do compile { target int128 } } */
+/* { dg-options "-O2" } */
+/* { dg-additional-options "-mavx" { target avx } } */
+
+__int128 j;
+int i;
+
+void
+foo (void)
+{
+  j <<= __builtin_parityll (i);
+}

	Jakub


^ permalink raw reply	[flat|nested] 4+ messages in thread

end of thread, other threads:[~2022-06-03 11:11 UTC | newest]

Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
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2022-06-03 10:17 [PATCH] i386: Fix up *_doubleword_mask [PR105825] Jakub Jelinek
2022-06-03 10:23 ` Uros Bizjak
2022-06-03 10:38   ` Jakub Jelinek
2022-06-03 11:10     ` Uros Bizjak

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