[AMDGPU] Make use of HasSMemRealTime predicate. NFC.

We have this subtarget feature so it makes sense to use it here. This is
NFC because it's always defined by default on GFX8+.

Differential Revision: https://reviews.llvm.org/D93202

Author: jayfoad

llvm/lib/Target/AMDGPU/AMDGPU.td

@@ -1264,6 +1264,9 @@ def HasGetWaveIdInst : Predicate<"Subtarget->hasGetWaveIdInst()">,
 def HasMAIInsts : Predicate<"Subtarget->hasMAIInsts()">,
   AssemblerPredicate<(all_of FeatureMAIInsts)>;
 
+def HasSMemRealTime : Predicate<"Subtarget->hasSMemRealTime()">,
+  AssemblerPredicate<(all_of FeatureSMemRealTime)>;
+
 def HasSMemTimeInst : Predicate<"Subtarget->hasSMemTimeInst()">,
   AssemblerPredicate<(all_of FeatureSMemTimeInst)>;
 

llvm/lib/Target/AMDGPU/SMInstructions.td

@@ -332,14 +332,16 @@ let OtherPredicates = [HasScalarStores] in {
 def S_DCACHE_WB     : SM_Inval_Pseudo <"s_dcache_wb", int_amdgcn_s_dcache_wb>;
 def S_DCACHE_WB_VOL : SM_Inval_Pseudo <"s_dcache_wb_vol", int_amdgcn_s_dcache_wb_vol>;
 } // End OtherPredicates = [HasScalarStores]
-def S_MEMREALTIME   : SM_Time_Pseudo <"s_memrealtime", int_amdgcn_s_memrealtime>;
 
 defm S_ATC_PROBE        : SM_Pseudo_Probe <"s_atc_probe", SReg_64>;
 let is_buffer = 1 in {
 defm S_ATC_PROBE_BUFFER : SM_Pseudo_Probe <"s_atc_probe_buffer", SReg_128>;
 }
 } // SubtargetPredicate = isGFX8Plus
 
+let SubtargetPredicate = HasSMemRealTime in
+def S_MEMREALTIME   : SM_Time_Pseudo <"s_memrealtime", int_amdgcn_s_memrealtime>;
+
 let SubtargetPredicate = isGFX10Plus in
 def S_GL1_INV : SM_Inval_Pseudo<"s_gl1_inv">;
 let SubtargetPredicate = HasGetWaveIdInst in