[llvm] [GlobalISel] Combine (X == 0) & (Y == 0) -> (X | Y) == 0 (PR #71949)

[Dávid Ferenc Szabó via llvm-commits]

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@@ -945,6 +945,37 @@ def redundant_binop_in_equality : GICombineRule<
          [{ return Helper.matchRedundantBinOpInEquality(*${root}, ${info}); }]),
   (apply [{ Helper.applyBuildFn(*${root}, ${info}); }])>;
 
+// Transform: (X == 0 & Y == 0) -> (X | Y) == 0
+def double_icmp_zero_and_combine: GICombineRule<
+  (defs root:$root),
+  (match (G_ICMP $d1, $p, $s1, 0),
+         (G_ICMP $d2, $p, $s2, 0),
+         (G_AND $root, $d1, $d2),
+         [{ return ${p}.getPredicate() == CmpInst::ICMP_EQ &&
+                       !MRI.getType(${s1}.getReg()).isPointer() &&
+                       (MRI.getType(${s1}.getReg()) ==
+                           MRI.getType(${s2}.getReg())); }]),
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dfszabo wrote:

I got this error when using it
`error: GISpecialType is not supported in 'match' patterns`

Maybe its only usable in the `apply` part atm.

https://github.com/llvm/llvm-project/pull/71949