[clang] [llvm] Minimal support of floating-point operand bundles (PR #135658)

[Serge Pavlov via cfe-commits]

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@@ -9355,6 +9357,56 @@ bool SelectionDAGBuilder::visitBinaryFloatCall(const CallInst &I,
   return true;
 }
 
+bool SelectionDAGBuilder::visitFPOperation(const CallInst &I, unsigned Opcode) {
+  // We already checked this call's prototype; verify it doesn't modify errno.
+  MemoryEffects ME = I.getMemoryEffects();
+  if (!ME.onlyAccessesInaccessibleMem())
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spavloff wrote:

It wouldn't make the check more correct. Actually the test for `onlyAccessesInaccessibleMem` is also excessive, as the call in this method is a call to an extern function, intrinsics are handles in another place. External functions have memory effects as "reads and writes all memories".

https://github.com/llvm/llvm-project/pull/135658