[llvm] Split vgpr regalloc pipeline (PR #93526)

[Christudasan Devadasan via llvm-commits]

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@@ -349,8 +349,12 @@ void SILowerSGPRSpills::determineRegsForWWMAllocation(MachineFunction &MF,
     }
   }
 
-  if (I != NumRegs)
-    report_fatal_error("Can't find enough VGPRs for wwm-regalloc");
+  if (I != NumRegs) {
+    // Reserve an arbitrary register and report the error.
+    TRI->markSuperRegs(RegMask, AMDGPU::VGPR0);
+    MF.getFunction().getContext().emitError(
+        "can't find enough VGPRs for wwm-regalloc");
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cdevadas wrote:

Yes, writing one and also, fixing the tests I made XFAIL.

https://github.com/llvm/llvm-project/pull/93526