[llvm] [BPF] Add asm support for JSET insn (PR #73161)

[via llvm-commits]

eddyz87 wrote:

Looks good as is, but I have a suggestion to minimize code duplication, seems to pass all tests.
Feel free to ignore if you think it's too hacky.

```diff
diff --git a/llvm/lib/Target/BPF/BPFInstrInfo.td b/llvm/lib/Target/BPF/BPFInstrInfo.td
index 9e75f35efe70..7a440cf94f5d 100644
--- a/llvm/lib/Target/BPF/BPFInstrInfo.td
+++ b/llvm/lib/Target/BPF/BPFInstrInfo.td
@@ -181,13 +181,18 @@ class TYPE_LD_ST<bits<3> mode, bits<2> size,
   let Inst{60-59} = size;
 }
 
+class NoCond : PatLeaf<(vt)> {}
+
 // jump instructions
 class JMP_RR<BPFJumpOp Opc, string OpcodeStr, PatLeaf Cond>
     : TYPE_ALU_JMP<Opc.Value, BPF_X.Value,
                    (outs),
                    (ins GPR:$dst, GPR:$src, brtarget:$BrDst),
                    "if $dst "#OpcodeStr#" $src goto $BrDst",
-                   [(BPFbrcc i64:$dst, i64:$src, Cond, bb:$BrDst)]> {
+                   !if(!isa<NoCond>(Cond),
+                       [],
+                       [(BPFbrcc i64:$dst, i64:$src, Cond, bb:$BrDst)])>
+{
   bits<4> dst;
   bits<4> src;
   bits<16> BrDst;
@@ -246,70 +251,6 @@ class JMP_RI_32<BPFJumpOp Opc, string OpcodeStr, PatLeaf Cond>
   let BPFClass = BPF_JMP32;
 }
 
-class JSET_RR<string OpcodeStr>
-    : TYPE_ALU_JMP<BPF_JSET.Value, BPF_X.Value,
-                   (outs),
-                   (ins GPR:$dst, GPR:$src, brtarget:$BrDst),
-                   "if $dst "#OpcodeStr#" $src goto $BrDst",
-                   []> {
-  bits<4> dst;
-  bits<4> src;
-  bits<16> BrDst;
-
-  let Inst{55-52} = src;
-  let Inst{51-48} = dst;
-  let Inst{47-32} = BrDst;
-  let BPFClass = BPF_JMP;
-}
-
-class JSET_RI<string OpcodeStr>
-    : TYPE_ALU_JMP<BPF_JSET.Value, BPF_K.Value,
-                   (outs),
-                   (ins GPR:$dst, i64imm:$imm, brtarget:$BrDst),
-                   "if $dst "#OpcodeStr#" $imm goto $BrDst",
-                   []> {
-  bits<4> dst;
-  bits<16> BrDst;
-  bits<32> imm;
-
-  let Inst{51-48} = dst;
-  let Inst{47-32} = BrDst;
-  let Inst{31-0} = imm;
-  let BPFClass = BPF_JMP;
-}
-
-class JSET_RR_32<string OpcodeStr>
-    : TYPE_ALU_JMP<BPF_JSET.Value, BPF_X.Value,
-                   (outs),
-                   (ins GPR32:$dst, GPR32:$src, brtarget:$BrDst),
-                   "if $dst "#OpcodeStr#" $src goto $BrDst",
-                   []> {
-  bits<4> dst;
-  bits<4> src;
-  bits<16> BrDst;
-
-  let Inst{55-52} = src;
-  let Inst{51-48} = dst;
-  let Inst{47-32} = BrDst;
-  let BPFClass = BPF_JMP32;
-}
-
-class JSET_RI_32<string OpcodeStr>
-    : TYPE_ALU_JMP<BPF_JSET.Value, BPF_K.Value,
-                   (outs),
-                   (ins GPR32:$dst, i32imm:$imm, brtarget:$BrDst),
-                   "if $dst "#OpcodeStr#" $imm goto $BrDst",
-                   []> {
-  bits<4> dst;
-  bits<16> BrDst;
-  bits<32> imm;
-
-  let Inst{51-48} = dst;
-  let Inst{47-32} = BrDst;
-  let Inst{31-0} = imm;
-  let BPFClass = BPF_JMP32;
-}
-
 multiclass J<BPFJumpOp Opc, string OpcodeStr, PatLeaf Cond, PatLeaf Cond32> {
   def _rr : JMP_RR<Opc, OpcodeStr, Cond>;
   def _ri : JMP_RI<Opc, OpcodeStr, Cond>;
@@ -329,10 +270,7 @@ defm JULT : J<BPF_JLT, "<", BPF_CC_LTU, BPF_CC_LTU_32>;
 defm JULE : J<BPF_JLE, "<=", BPF_CC_LEU, BPF_CC_LEU_32>;
 defm JSLT : J<BPF_JSLT, "s<", BPF_CC_LT, BPF_CC_LT_32>;
 defm JSLE : J<BPF_JSLE, "s<=", BPF_CC_LE, BPF_CC_LE_32>;
-def JSET_RR    : JSET_RR<"&">;
-def JSET_RI    : JSET_RI<"&">;
-def JSET_RR_32 : JSET_RR_32<"&">;
-def JSET_RI_32 : JSET_RI_32<"&">;
+defm JSET : J<BPF_JSET, "&", NoCond<>, NoCond<>>;
 }
 
 // ALU instructions
```

https://github.com/llvm/llvm-project/pull/73161