[NVPTX] Add unreachable for TMA Inst Printer

[durga4github]

This patch adds the llvm_reachable() for TMA
reduction opcode printer method, outside the
switch.

We had this inside the default-case leading to
the warning below (and hence was removed):
error: default label in switch which covers all enumeration values
[-Werror,-Wcovered-switch-default]

[llvmbot]

@llvm/pr-subscribers-backend-nvptx

Author: Durgadoss R (durga4github)

Changes

This patch adds the llvm_reachable() for TMA
reduction opcode printer method.

We had this inside the default-case leading to
warning below (and hence was removed):
error: default label in switch which covers all enumeration values
[-Werror,-Wcovered-switch-default]

---

Full diff: https://github.com/llvm/llvm-project/pull/117850.diff

1 Files Affected:

• (modified) llvm/lib/Target/NVPTX/MCTargetDesc/NVPTXInstPrinter.cpp (+2)

diff --git a/llvm/lib/Target/NVPTX/MCTargetDesc/NVPTXInstPrinter.cpp b/llvm/lib/Target/NVPTX/MCTargetDesc/NVPTXInstPrinter.cpp
index 0f38f644e89af5..65e1893d3f3bdf 100644
--- a/llvm/lib/Target/NVPTX/MCTargetDesc/NVPTXInstPrinter.cpp
+++ b/llvm/lib/Target/NVPTX/MCTargetDesc/NVPTXInstPrinter.cpp
@@ -450,4 +450,6 @@ void NVPTXInstPrinter::printTmaReductionMode(const MCInst *MI, int OpNum,
     O << ".xor";
     return;
   }
+  llvm_unreachable(
+      "Invalid Reduction Op in printCpAsyncBulkTensorReductionMode");
 }

[durga4github]

@kazutakahirata , Could you please review this?

[kazutakahirata]

LGTM. Thanks!