[PATCH] i386: Fix up *3_doubleword_mask [PR105911

[Jakub Jelinek via Gcc-patches]

Hi!

Another regression caused by my recent patch.

This time because define_insn_and_split only requires that the
constant mask is const_int_operand.  When it was only SImode,
that wasn't a problem, HImode neither, but for DImode if we need
to and the shift count we might run into a problem that it isn't
a representable signed 32-bit immediate.

But, we don't really care about the upper bits of the mask, so
we can just mask the CONST_INT with the mode mask.

Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?

2022-06-10  Jakub Jelinek  <ja...@redhat.com>

        PR target/105911
        * config/i386/i386.md ((*ashl<dwi>3_doubleword_mask,
        *<insn><dwi>3_doubleword_mask): Use operands[3] masked with
        (<MODE_SIZE> * BITS_PER_UNIT) - 1 as AND operand instead of
        operands[3] unmodified.

        * gcc.dg/pr105911.c: New test.

--- gcc/config/i386/i386.md.jj  2022-06-08 08:21:26.000000000 +0200
+++ gcc/config/i386/i386.md     2022-06-10 11:37:21.931171567 +0200
@@ -11937,7 +11937,8 @@ (define_insn_and_split "*ashl<dwi>3_doub
       rtx xops[3];
       xops[0] = gen_reg_rtx (GET_MODE (operands[2]));
       xops[1] = operands[2];
-      xops[2] = operands[3];
+      xops[2] = GEN_INT (INTVAL (operands[3])
+                        & ((<MODE_SIZE> * BITS_PER_UNIT) - 1));
       ix86_expand_binary_operator (AND, GET_MODE (operands[2]), xops);
       operands[2] = xops[0];
     }
@@ -12905,7 +12906,8 @@ (define_insn_and_split "*<insn><dwi>3_do
       rtx xops[3];
       xops[0] = gen_reg_rtx (GET_MODE (operands[2]));
       xops[1] = operands[2];
-      xops[2] = operands[3];
+      xops[2] = GEN_INT (INTVAL (operands[3])
+                        & ((<MODE_SIZE> * BITS_PER_UNIT) - 1));
       ix86_expand_binary_operator (AND, GET_MODE (operands[2]), xops);
       operands[2] = xops[0];
     }
--- gcc/testsuite/gcc.dg/pr105911.c.jj  2022-06-10 11:45:38.314044503 +0200
+++ gcc/testsuite/gcc.dg/pr105911.c     2022-06-10 11:45:18.068253633 +0200
@@ -0,0 +1,16 @@
+/* PR target/105911 */
+/* { dg-do compile { target int128 } } */
+/* { dg-options "-O2" } */
+
+__int128 v, x;
+unsigned __int128 w;
+
+void bar (__int128, __int128);
+
+void
+foo (void)
+{
+  bar (v /= v, v >> (v &= 0x100000001));
+  bar (w /= w, w >> (w &= 0x300000003));
+  bar (x /= x, x << (x &= 0x700000007));
+}

        Jakub