test regalloc isa riscv ; Test the coalescer. ; regex: V=v\d+ ; regex: WS=\s+ ; This function is already CSSA, so no copies should be inserted. function %cssa(i32) -> i32 { ebb0(v0: i32): ; not: copy ; v0 is used by the branch and passed as an arg - that's no conflict. brnz v0, ebb1(v0) ; v0 is live across the branch above. That's no conflict. v1 = iadd_imm v0, 7 jump ebb1(v1) ebb1(v10: i32): v11 = iadd_imm v10, 7 return v11 } function %trivial(i32) -> i32 { ebb0(v0: i32): ; check: $(cp1=$V) = copy $v0 ; nextln: brnz $v0, $ebb1($cp1) brnz v0, ebb1(v0) ; not: copy v1 = iadd_imm v0, 7 jump ebb1(v1) ebb1(v10: i32): ; Use v0 in the destination EBB causes a conflict. v11 = iadd v10, v0 return v11 } ; A value is used as an SSA argument twice in the same branch. function %dualuse(i32) -> i32 { ebb0(v0: i32): ; check: $(cp1=$V) = copy $v0 ; nextln: brnz $v0, $ebb1($v0, $cp1) brnz v0, ebb1(v0, v0) ; not: copy v1 = iadd_imm v0, 7 v2 = iadd_imm v1, 56 jump ebb1(v1, v2) ebb1(v10: i32, v11: i32): v12 = iadd v10, v11 return v12 } ; Interference away from the branch ; The interference can be broken with a copy at either branch. function %interference(i32) -> i32 { ebb0(v0: i32): ; not: copy brnz v0, ebb1(v0) v1 = iadd_imm v0, 7 ; v1 and v0 interfere here: v2 = iadd_imm v0, 8 ; check: $(cp1=$V) = copy $v1 ; not: copy ; check: jump $ebb1($cp1) jump ebb1(v1) ebb1(v10: i32): ; not: copy v11 = iadd_imm v10, 7 return v11 } ; A loop where one induction variable is used as a backedge argument. function %fibonacci(i32) -> i32 { ebb0(v0: i32): ; not: copy v1 = iconst.i32 1 v2 = iconst.i32 2 jump ebb1(v1, v2) ebb1(v10: i32, v11: i32): ; v11 needs to be isolated because it interferes with v10. ; check: $ebb1($v10: i32, $(nv11a=$V): i32) ; check: $v11 = copy $nv11a v12 = iadd v10, v11 v13 = icmp ult v12, v0 ; check: $(nv11b=$V) = copy $v11 ; not: copy ; check: brnz $v13, $ebb1($nv11b, $v12) brnz v13, ebb1(v11, v12) return v12 } ; Function arguments passed on the stack aren't allowed to be part of a virtual ; register, at least for now. This is because the other values in the virtual ; register would need to be spilled to the incoming_arg stack slot which we treat ; as belonging to the caller. function %stackarg(i32, i32, i32, i32, i32, i32, i32, i32, i32) -> i32 { ; check: ss0 = incoming_arg 4 ; not: incoming_arg ebb0(v0: i32, v1: i32, v2: i32, v3: i32, v4: i32, v5: i32, v6: i32, v7: i32, v8: i32): ; check: fill v8 ; not: v8 brnz v0, ebb1(v8) jump ebb1(v7) ebb1(v10: i32): v11 = iadd_imm v10, 1 return v11 }