[AMDGPU] Fix predicates for BUFFER_ATOMIC_CSUB pattern (#78701)

Use OtherPredicates to avoid interfering with other uses of
SubtargetPredicate for GFX12.

Author: jayfoad

llvm/lib/Target/AMDGPU/BUFInstructions.td

@@ -1712,7 +1712,7 @@ defm : SIBufferAtomicPat<"SIbuffer_atomic_xor", i64, "BUFFER_ATOMIC_XOR_X2">;
 defm : SIBufferAtomicPat<"SIbuffer_atomic_inc", i64, "BUFFER_ATOMIC_INC_X2">;
 defm : SIBufferAtomicPat<"SIbuffer_atomic_dec", i64, "BUFFER_ATOMIC_DEC_X2">;
 
-let SubtargetPredicate = HasAtomicCSubNoRtnInsts in
+let OtherPredicates = [HasAtomicCSubNoRtnInsts] in
 defm : SIBufferAtomicPat<"SIbuffer_atomic_csub", i32, "BUFFER_ATOMIC_CSUB", ["noret"]>;
 
 let SubtargetPredicate = isGFX12Plus in {

llvm/test/CodeGen/AMDGPU/llvm.amdgcn.atomic.csub.ll

@@ -16,7 +16,7 @@ main_body:
 
 ; GCN-LABEL: {{^}}buffer_atomic_csub_no_rtn:
 ; PREGFX12: buffer_atomic_csub v0, v1, s[0:3], 0 idxen
-; GFX12PLUS: buffer_atomic_csub_u32 v0, v1, s[0:3], null idxen
+; GFX12PLUS: buffer_atomic_sub_clamp_u32 v0, v1, s[0:3], null idxen
 define amdgpu_ps void @buffer_atomic_csub_no_rtn(<4 x i32> inreg %rsrc, i32 %data, i32 %vindex) #0 {
 main_body:
   %ret = call i32 @llvm.amdgcn.buffer.atomic.csub(i32 %data, <4 x i32> %rsrc, i32 %vindex, i32 0, i1 0)
@@ -34,7 +34,7 @@ main_body:
 
 ; GCN-LABEL: {{^}}buffer_atomic_csub_off4_slc_no_rtn:
 ; PREGFX12: buffer_atomic_csub v0, v1, s[0:3], 0 idxen offset:4 slc
-; GFX12PLUS: buffer_atomic_csub_u32 v0, v1, s[0:3], null idxen offset:4 th:TH_ATOMIC_NT
+; GFX12PLUS: buffer_atomic_sub_clamp_u32 v0, v1, s[0:3], null idxen offset:4 th:TH_ATOMIC_NT
 define amdgpu_ps void @buffer_atomic_csub_off4_slc_no_rtn(<4 x i32> inreg %rsrc, i32 %data, i32 %vindex) #0 {
 main_body:
   %ret = call i32 @llvm.amdgcn.buffer.atomic.csub(i32 %data, <4 x i32> %rsrc, i32 %vindex, i32 4, i1 1)