[llvm-branch-commits] [llvm] [AMDGPU] Intrinsic for launching whole wave functions (PR #145859)

[Matt Arsenault via llvm-branch-commits]

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@@ -1465,9 +1465,22 @@ bool AMDGPUCallLowering::lowerCall(MachineIRBuilder &MIRBuilder,
                                    CallLoweringInfo &Info) const {
   if (Function *F = Info.CB->getCalledFunction())
     if (F->isIntrinsic()) {
-      assert(F->getIntrinsicID() == Intrinsic::amdgcn_cs_chain &&
-             "Unexpected intrinsic");
-      return lowerChainCall(MIRBuilder, Info);
+      switch (F->getIntrinsicID()) {
+      case Intrinsic::amdgcn_cs_chain:
+        return lowerChainCall(MIRBuilder, Info);
+      case Intrinsic::amdgcn_call_whole_wave:
+        Info.CallConv = CallingConv::AMDGPU_Gfx_WholeWave;
+
+        // Get the callee from the original instruction, so it doesn't look like
+        // this is an indirect call.
+        Info.Callee = MachineOperand::CreateGA(
+            static_cast<GlobalValue *>(Info.CB->getOperand(0)), /*Offset=*/0);
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arsenm wrote:

Don't use static_cast for IR classes 

https://github.com/llvm/llvm-project/pull/145859