[llvm] [IR] Add CallBr intrinsics support (PR #133907)

[Matt Arsenault via llvm-commits]

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@@ -3007,10 +3024,59 @@ bool IRTranslator::translateInvoke(const User &U,
   return true;
 }
 
+/// The intrinsics currently supported by callbr are implicit control flow
+/// intrinsics such as amdgcn.kill.
 bool IRTranslator::translateCallBr(const User &U,
                                    MachineIRBuilder &MIRBuilder) {
-  // FIXME: Implement this.
-  return false;
+  if (containsBF16Type(U))
+    return false; // see translateCall
+
+  const CallBrInst &I = cast<CallBrInst>(U);
+  MachineBasicBlock *CallBrMBB = &MIRBuilder.getMBB();
+
+  if (I.isInlineAsm()) {
+    // FIXME: inline asm not yet supported
+    if (!translateInlineAsm(I, MIRBuilder))
+      return false;
+  } else if (I.getIntrinsicID() != Intrinsic::not_intrinsic) {
+    switch (I.getIntrinsicID()) {
+    default:
+      report_fatal_error("Unsupported intrinsic for callbr");
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arsenm wrote:

Ditto, return false (and error messages should start with lowercase)

https://github.com/llvm/llvm-project/pull/133907