[clang] [llvm] [RFC][BPF] Do atomic_fetch_*() pattern matching with memory ordering (PR #107343)

[via cfe-commits]

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@@ -864,26 +864,119 @@ class XFALU32<BPFWidthModifer SizeOp, BPFArithOp Opc, string OpcodeStr,
 
 let Constraints = "$dst = $val" in {
   let Predicates = [BPFHasALU32], DecoderNamespace = "BPFALU32" in {
-    def XFADDW32 : XFALU32<BPF_W, BPF_ADD, "u32", "add", atomic_load_add_i32>;
-    def XFANDW32 : XFALU32<BPF_W, BPF_AND, "u32", "and", atomic_load_and_i32>;
-    def XFORW32  : XFALU32<BPF_W, BPF_OR,  "u32", "or",  atomic_load_or_i32>;
-    def XFXORW32 : XFALU32<BPF_W, BPF_XOR, "u32", "xor", atomic_load_xor_i32>;
+    def XFADDW32 : XFALU32<BPF_W, BPF_ADD, "u32", "add", atomic_load_add_i32_seq_cst>;
+    def XFANDW32 : XFALU32<BPF_W, BPF_AND, "u32", "and", atomic_load_and_i32_seq_cst>;
+    def XFORW32  : XFALU32<BPF_W, BPF_OR,  "u32", "or",  atomic_load_or_i32_seq_cst>;
+    def XFXORW32 : XFALU32<BPF_W, BPF_XOR, "u32", "xor", atomic_load_xor_i32_seq_cst>;
   }
 
   let Predicates = [BPFHasALU32] in {
-    def XFADDD : XFALU64<BPF_DW, BPF_ADD, "u64", "add", atomic_load_add_i64>;
+    def XFADDD : XFALU64<BPF_DW, BPF_ADD, "u64", "add", atomic_load_add_i64_seq_cst>;
   }
-  def XFANDD : XFALU64<BPF_DW, BPF_AND, "u64", "and", atomic_load_and_i64>;
-  def XFORD  : XFALU64<BPF_DW, BPF_OR,  "u64", "or",  atomic_load_or_i64>;
-  def XFXORD : XFALU64<BPF_DW, BPF_XOR, "u64", "xor", atomic_load_xor_i64>;
+  def XFANDD : XFALU64<BPF_DW, BPF_AND, "u64", "and", atomic_load_and_i64_seq_cst>;
+  def XFORD  : XFALU64<BPF_DW, BPF_OR,  "u64", "or",  atomic_load_or_i64_seq_cst>;
+  def XFXORD : XFALU64<BPF_DW, BPF_XOR, "u64", "xor", atomic_load_xor_i64_seq_cst>;
+}
+
+let Predicates = [BPFHasALU32] in {
+    def : Pat<(atomic_load_add_i32_monotonic ADDRri:$addr, GPR32:$val),
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eddyz87 wrote:

We guard add operation with `BPFHasALU32`, but not or/xor/and, why?

https://github.com/llvm/llvm-project/pull/107343