[llvm] [AMDGPU] Use subtarget call to determine number of VGPRs (PR #157927)

[Matt Arsenault via llvm-commits]

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@@ -86,7 +86,7 @@ SIMachineFunctionInfo::SIMachineFunctionInfo(const Function &F,
     // FIXME: MayNeedAGPRs is a misnomer for how this is used. MFMA selection
     // should be separated from availability of AGPRs
     if (MFMAVGPRForm ||
-        (ST.getMaxNumVGPRs(F) <= AMDGPU::VGPR_32RegClass.getNumRegs() &&
+        (ST.getMaxNumVGPRs(F) <= ST.getAddressableNumArchVGPRs() &&
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arsenm wrote:

I'm working on deleting this part 

https://github.com/llvm/llvm-project/pull/157927