[llvm] [AMDGPU] Enable kernel arg preloading with gfx90a (PR #81180)

[Matt Arsenault via llvm-commits]

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@@ -1254,12 +1254,6 @@ class GCNSubtarget final : public AMDGPUGenSubtargetInfo,
   // \returns true if preloading kernel arguments is supported.
   bool hasKernargPreload() const { return KernargPreload; }
 
-  // \returns true if we need to generate backwards compatible code when
-  // preloading kernel arguments.
-  bool needsKernargPreloadBackwardsCompatibility() const {
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arsenm wrote:

Isn't this still needed if you're just adding a new debug trap?

https://github.com/llvm/llvm-project/pull/81180