[llvm] `__builtin.canonicalize` in common code (PR #142105)

[Matt Arsenault via llvm-commits]

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@@ -3356,6 +3356,23 @@ bool SelectionDAGLegalize::ExpandNode(SDNode *Node) {
     Results.push_back(Op);
     break;
   }
+  case ISD::FCANONICALIZE: {
+    // This implements llvm.canonicalize.f* by multiplication with 1.0,
+    // as suggested in https://llvm.org/docs/LangRef.html#id2335.
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arsenm wrote:

This should probably elaborate on how this is hacking in strictfp operations in non-strict functions 

https://github.com/llvm/llvm-project/pull/142105