[llvm] Add support for x87 registers on GISel register selection (PR #83528)

[Matt Arsenault via llvm-commits]

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@@ -415,17 +416,19 @@ X86LegalizerInfo::X86LegalizerInfo(const X86Subtarget &STI,
   // fp constants
   getActionDefinitionsBuilder(G_FCONSTANT)
       .legalIf([=](const LegalityQuery &Query) -> bool {
-        return (HasSSE1 && typeInSet(0, {s32})(Query)) ||
-               (HasSSE2 && typeInSet(0, {s64})(Query));
+        return (typeInSet(0, {s32, s64})(Query)) ||
+               (UseX87 && typeInSet(0, {s80})(Query));
       });
 
   // fp arithmetic
   getActionDefinitionsBuilder({G_FADD, G_FSUB, G_FMUL, G_FDIV})
       .legalIf([=](const LegalityQuery &Query) {
-        return (HasSSE1 && typeInSet(0, {s32, v4s32})(Query)) ||
-               (HasSSE2 && typeInSet(0, {s64, v2s64})(Query)) ||
+        return (typeInSet(0, {s32, s64})(Query)) ||
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arsenm wrote:

Existing issue but I think this is an overly verbose way of expressing the simplest type of operation with a single type operand 

https://github.com/llvm/llvm-project/pull/83528