[PATCH] D133417: [RISCV] Added optimization patterns with Zbb extension

[Craig Topper via Phabricator via llvm-commits]

craig.topper added inline comments.


================
Comment at: llvm/test/CodeGen/RISCV/minu_xori.ll:5
+
+define i1 @test(i64 %c, i64 %a, i64 %b) {
+entry:
----------------
The DAG for this before isel looks like

```
SelectionDAG has 16 nodes:                                                       
  t0: ch = EntryToken                                                            
  t2: i64,ch = CopyFromReg t0, Register:i64 %0                                   
          t4: i64,ch = CopyFromReg t0, Register:i64 %1                           
        t22: i64 = setcc t4, t2, setult:ch                                       
          t6: i64,ch = CopyFromReg t0, Register:i64 %2                           
        t19: i64 = setcc t6, t2, setult:ch                                       
      t26: i64 = or t22, t19                                                     
    t27: i64 = xor t26, Constant:i64<1>                                          
  t13: ch,glue = CopyToReg t0, Register:i64 $x10, t27                            
  t14: ch = RISCVISD::RET_FLAG t13, Register:i64 $x10, t13:1 
```

There is no AND, the XOR with 1 was already created.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D133417/new/

https://reviews.llvm.org/D133417