diff --git a/llvm/lib/Target/AMDGPU/AMDGPU.td b/llvm/lib/Target/AMDGPU/AMDGPU.td
--- a/llvm/lib/Target/AMDGPU/AMDGPU.td
+++ b/llvm/lib/Target/AMDGPU/AMDGPU.td
@@ -1558,13 +1558,6 @@
 def HasAtomicFaddInsts : Predicate<"Subtarget->hasAtomicFaddInsts()">,
   AssemblerPredicate<(all_of FeatureAtomicFaddInsts)>;
 
-// Differentiate between two functionally equivalent, but incompatible
-// encoding-wise FP atomics between gfx90* and gfx940
-def HasAtomicFaddInstsGFX90X : Predicate<"Subtarget->hasAtomicFaddInsts()">,
-  AssemblerPredicate<(all_of FeatureAtomicFaddInsts, (not FeatureGFX940Insts))>;
-def HasAtomicFaddInstsGFX940 : Predicate<"Subtarget->hasAtomicFaddInsts()">,
-  AssemblerPredicate<(all_of FeatureAtomicFaddInsts, FeatureGFX940Insts)>;
-
 def HasDsSrc2Insts : Predicate<"!Subtarget->hasDsSrc2Insts()">,
   AssemblerPredicate<(all_of FeatureDsSrc2Insts)>;
 
diff --git a/llvm/lib/Target/AMDGPU/FLATInstructions.td b/llvm/lib/Target/AMDGPU/FLATInstructions.td
--- a/llvm/lib/Target/AMDGPU/FLATInstructions.td
+++ b/llvm/lib/Target/AMDGPU/FLATInstructions.td
@@ -1596,9 +1596,10 @@
 defm SCRATCH_STORE_DWORDX3      : FLAT_Real_AllAddr_vi <0x1e>;
 defm SCRATCH_STORE_DWORDX4      : FLAT_Real_AllAddr_vi <0x1f>;
 
-let SubtargetPredicate = HasAtomicFaddInstsGFX90X in {
-defm GLOBAL_ATOMIC_ADD_F32    : FLAT_Global_Real_Atomics_vi <0x04d, 0>;
-defm GLOBAL_ATOMIC_PK_ADD_F16 : FLAT_Global_Real_Atomics_vi <0x04e, 0>;
+let SubtargetPredicate = isGFX8GFX9NotGFX940 in {
+  // These instructions are encoded differently on gfx90* and gfx940.
+  defm GLOBAL_ATOMIC_ADD_F32    : FLAT_Global_Real_Atomics_vi <0x04d, 0>;
+  defm GLOBAL_ATOMIC_PK_ADD_F16 : FLAT_Global_Real_Atomics_vi <0x04e, 0>;
 }
 
 let SubtargetPredicate = isGFX90AOnly in {
@@ -1626,12 +1627,11 @@
   def _SADDR_RTN_gfx940 : FLAT_Real_gfx940 <op, !cast<FLAT_Pseudo>(NAME#"_SADDR_RTN")>;
 }
 
-let SubtargetPredicate = HasAtomicFaddInstsGFX940 in {
+let SubtargetPredicate = isGFX940Plus in {
+  // These instructions are encoded differently on gfx90* and gfx940.
   defm GLOBAL_ATOMIC_ADD_F32     : FLAT_Global_Real_Atomics_gfx940 <0x04d>;
   defm GLOBAL_ATOMIC_PK_ADD_F16  : FLAT_Global_Real_Atomics_gfx940 <0x04e>;
-}
 
-let SubtargetPredicate = isGFX940Plus in {
   defm FLAT_ATOMIC_ADD_F64       : FLAT_Real_Atomics_gfx940<0x4f, FLAT_ATOMIC_ADD_F64>;
   defm FLAT_ATOMIC_MIN_F64       : FLAT_Real_Atomics_gfx940<0x50, FLAT_ATOMIC_MIN_F64>;
   defm FLAT_ATOMIC_MAX_F64       : FLAT_Real_Atomics_gfx940<0x51, FLAT_ATOMIC_MAX_F64>;