[AMDGPU] Parse wwm filter flag for regalloc fast (#119347)

Author: optimisan

llvm/lib/Target/AMDGPU/AMDGPUTargetMachine.cpp

@@ -879,6 +879,8 @@ void AMDGPUTargetMachine::registerPassBuilderCallbacks(PassBuilder &PB) {
           return onlyAllocateSGPRs;
         if (FilterName == "vgpr")
           return onlyAllocateVGPRs;
+        if (FilterName == "wwm")
+          return onlyAllocateWWMRegs;
         return nullptr;
       });
 }

llvm/test/tools/llc/new-pm/regalloc-amdgpu.mir

@@ -1,8 +1,10 @@
 # REQUIRES: amdgpu-registered-target
-# RUN: llc -mtriple=amdgcn --passes='regallocfast<filter=sgpr>' --print-pipeline-passes --filetype=null %s | FileCheck %s --check-prefix=PASS
+# RUN: llc -mtriple=amdgcn --passes='regallocfast<filter=sgpr>,regallocfast<filter=wwm>,regallocfast<filter=vgpr>' --print-pipeline-passes --filetype=null %s | FileCheck %s --check-prefix=PASS
 # RUN: not llc -mtriple=amdgcn --passes='regallocfast<filter=bad-filter>' --print-pipeline-passes --filetype=null %s 2>&1 | FileCheck %s --check-prefix=BAD-FILTER
 
 # PASS: regallocfast<filter=sgpr>
+# PASS: regallocfast<filter=wwm>
+# PASS: regallocfast<filter=vgpr>
 # BAD-FILTER: invalid regallocfast register filter 'bad-filter'
 
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