[llvm] [ARM] Use FPRegs for fastcc calling convention detection. (PR #184593)

[David Green via llvm-commits]

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@@ -1714,10 +1714,10 @@ ARMTargetLowering::getEffectiveCallingConv(CallingConv::ID CC,
   case CallingConv::Fast:
   case CallingConv::CXX_FAST_TLS:
     if (!getTM().isAAPCS_ABI()) {
-      if (Subtarget->hasVFP2Base() && !Subtarget->isThumb1Only() && !isVarArg)
+      if (Subtarget->hasFPRegs() && !Subtarget->isThumb1Only() && !isVarArg)
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davemgreen wrote:

I've changed it over and added some tests, but I'm not sure this is easily reachable. fast-isel is only enabled for certain targets, and doesn't handle many if any vector operations. But they should now be consistent.

https://github.com/llvm/llvm-project/pull/184593