[llvm] [X86][GlobalISel] - Legalize And Select of G_FPTOSI/G_SITOFP in X87 mode (PR #137377)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,31 @@
+//===- X86InstrGISel.td - X86 GISel target specific opcodes -*- tablegen -*===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// X86 GlobalISel target pseudo instruction definitions. This is kept
+// separately from the other tablegen files for organizational purposes, but
+// share the same infrastructure.
+//
+//===----------------------------------------------------------------------===//
+
+class X86GenericInstruction : GenericInstruction { let Namespace = "X86"; }
+
+def G_FILD : X86GenericInstruction {
+  let OutOperandList = (outs type0:$dst);
+  let InOperandList = (ins ptype1:$src);
+  let hasSideEffects = false;
+  let mayLoad = true;
+}
+def G_FIST : X86GenericInstruction {
+  let OutOperandList = (outs);
+  let InOperandList = (ins type0:$src1, ptype1:$src2);
+  let hasSideEffects = false;
+  let mayStore = true;
+}
+
+def : GINodeEquiv<G_FILD, X86fild>;
+def : GINodeEquiv<G_FIST, X86fp_to_mem>;
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arsenm wrote:

```suggestion
def : GINodeEquiv<G_FIST, X86fp_to_mem>;

```

https://github.com/llvm/llvm-project/pull/137377