[llvm] [AMDGPU] Fix predicates on FLAT scratch ST/SVS mode Pseudos (PR #85442)

[Joe Nash via llvm-commits]

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@@ -428,37 +430,33 @@ class FLAT_Scratch_Store_Pseudo <string opName, RegisterClass vdataClass, bit En
 }
 
 multiclass FLAT_Scratch_Load_Pseudo<string opName, RegisterClass regClass, bit HasTiedOutput = 0> {
-  let is_flat_scratch = 1 in {
-    def "" : FLAT_Scratch_Load_Pseudo<opName, regClass, HasTiedOutput>,
-             FlatScratchInst<opName, "SV">;
-    def _SADDR : FLAT_Scratch_Load_Pseudo<opName, regClass, HasTiedOutput, 1>,
-                 FlatScratchInst<opName, "SS">;
-
-    let SubtargetPredicate = HasFlatScratchSVSMode in
-    def _SVS : FLAT_Scratch_Load_Pseudo<opName, regClass, HasTiedOutput, 1, 1>,
-               FlatScratchInst<opName, "SVS">;
+  def "" : FLAT_Scratch_Load_Pseudo<opName, regClass, HasTiedOutput>,
+           FlatScratchInst<opName, "SV">;
+  def _SADDR : FLAT_Scratch_Load_Pseudo<opName, regClass, HasTiedOutput, 1>,
+               FlatScratchInst<opName, "SS">;
 
-    let SubtargetPredicate = HasFlatScratchSTMode in
-    def _ST  : FLAT_Scratch_Load_Pseudo<opName, regClass, HasTiedOutput, 0, 0, 0>,
-               FlatScratchInst<opName, "ST">;
-  }
+  let SubtargetPredicate = HasFlatScratchSVSMode in
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Sisyph wrote:

Nit: make this use OtherPredicates because it is not exactly a SubtargetPredicate? Here and on 442

https://github.com/llvm/llvm-project/pull/85442