[llvm] AMDGPU: Handle gfx950XDL Write VGPR wait state change (PR #126132)

[via llvm-commits]

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@@ -2290,12 +2290,14 @@ GFX940_SMFMA_N_PassWritesVGPROverlappedSrcABWaitStates(int NumPasses) {
   return NumPasses + 2;
 }
 
-static int GFX940_XDL_N_PassWritesVGPROverlappedSrcABWaitStates(int NumPasses) {
-  // 2 pass -> 5
-  // 4 pass -> 7
-  // 8 pass -> 11
-  // 16 pass -> 19
-  return NumPasses + 3;
+static int GFX940_XDL_N_PassWritesVGPROverlappedSrcABWaitStates(int NumPasses,
+                                                                bool IsGFX950) {
+  // xdl def cycles | gfx940 | gfx950
+  // 2 pass         |  5        5
+  // 4 pass         |  7        8
+  // 8 pass         |  11       12
+  // 16 pass        |  19       20
+  return NumPasses + 3 + (NumPasses != 2 && IsGFX950);
 }
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bcahoon wrote:

Hi @scchan, that's a good point about generic targets. Should that be handled with a separate patch? 

https://github.com/llvm/llvm-project/pull/126132