[llvm] [CodeGen][NewPM] Handle `--regalloc-npm` option (PR #94748)

[Matt Arsenault via llvm-commits]

================
@@ -749,6 +752,30 @@ void AMDGPUTargetMachine::registerPassBuilderCallbacks(
           return onlyAllocateVGPRs;
         return nullptr;
       });
+
+  PB.setDefaultRegAllocBuilder(
+      [TM = this](StringMap<MachineFunctionPassManager> &RegAllocMap) {
+        auto Opts = getCGPassBuilderOption();
+        if (Opts.OptimizeRegAlloc.value_or(TM->getOptLevel() !=
+                                           CodeGenOptLevel::None)) {
+          // TODO: Add greedy register allocator.
+        } else {
+          RegAllocFastPassOptions Opts;
----------------
arsenm wrote:

SGPRRunOpts

https://github.com/llvm/llvm-project/pull/94748