Files
clang-p2996/mlir/test/Dialect/ControlFlow/canonicalize.mlir
Matthias Springer e7790fbed3 [mlir] Add test-convergence option to Canonicalizer tests
This new option is set to `false` by default. It should  be set only in Canonicalizer tests to detect faulty canonicalization patterns. I.e., patterns that prevent the canonicalizer from converging. The canonicalizer should always convergence on such small unit tests that we have in `canonicalize.mlir`.

Two faulty canonicalization patterns were detected and fixed with this change.

Differential Revision: https://reviews.llvm.org/D140873
2023-01-04 12:02:21 +01:00

468 lines
14 KiB
MLIR

// RUN: mlir-opt %s -allow-unregistered-dialect -pass-pipeline='builtin.module(func.func(canonicalize{test-convergence}))' -split-input-file | FileCheck --dump-input-context 20 %s
/// Test the folding of BranchOp.
// CHECK-LABEL: func @br_folding(
func.func @br_folding() -> i32 {
// CHECK-NEXT: %[[CST:.*]] = arith.constant 0 : i32
// CHECK-NEXT: return %[[CST]] : i32
%c0_i32 = arith.constant 0 : i32
cf.br ^bb1(%c0_i32 : i32)
^bb1(%x : i32):
return %x : i32
}
/// Test that pass-through successors of BranchOp get folded.
// CHECK-LABEL: func @br_passthrough(
// CHECK-SAME: %[[ARG0:.*]]: i32, %[[ARG1:.*]]: i32
func.func @br_passthrough(%arg0 : i32, %arg1 : i32) -> (i32, i32) {
"foo.switch"() [^bb1, ^bb2, ^bb3] : () -> ()
^bb1:
// CHECK: ^bb1:
// CHECK-NEXT: cf.br ^bb3(%[[ARG0]], %[[ARG1]] : i32, i32)
cf.br ^bb2(%arg0 : i32)
^bb2(%arg2 : i32):
cf.br ^bb3(%arg2, %arg1 : i32, i32)
^bb3(%arg4 : i32, %arg5 : i32):
return %arg4, %arg5 : i32, i32
}
/// Test the folding of CondBranchOp with a constant condition.
// CHECK-LABEL: func @cond_br_folding(
func.func @cond_br_folding(%cond : i1, %a : i32) {
// CHECK-NEXT: return
%false_cond = arith.constant false
%true_cond = arith.constant true
cf.cond_br %cond, ^bb1, ^bb2(%a : i32)
^bb1:
cf.cond_br %true_cond, ^bb3, ^bb2(%a : i32)
^bb2(%x : i32):
cf.cond_br %false_cond, ^bb2(%x : i32), ^bb3
^bb3:
return
}
/// Test the folding of CondBranchOp when the successors are identical.
// CHECK-LABEL: func @cond_br_same_successor(
func.func @cond_br_same_successor(%cond : i1, %a : i32) {
// CHECK-NEXT: return
cf.cond_br %cond, ^bb1(%a : i32), ^bb1(%a : i32)
^bb1(%result : i32):
return
}
/// Test the folding of CondBranchOp when the successors are identical, but the
/// arguments are different.
// CHECK-LABEL: func @cond_br_same_successor_insert_select(
// CHECK-SAME: %[[COND:.*]]: i1, %[[ARG0:.*]]: i32, %[[ARG1:.*]]: i32
// CHECK-SAME: %[[ARG2:.*]]: tensor<2xi32>, %[[ARG3:.*]]: tensor<2xi32>
func.func @cond_br_same_successor_insert_select(
%cond : i1, %a : i32, %b : i32, %c : tensor<2xi32>, %d : tensor<2xi32>
) -> (i32, tensor<2xi32>) {
// CHECK: %[[RES:.*]] = arith.select %[[COND]], %[[ARG0]], %[[ARG1]]
// CHECK: %[[RES2:.*]] = arith.select %[[COND]], %[[ARG2]], %[[ARG3]]
// CHECK: return %[[RES]], %[[RES2]]
cf.cond_br %cond, ^bb1(%a, %c : i32, tensor<2xi32>), ^bb1(%b, %d : i32, tensor<2xi32>)
^bb1(%result : i32, %result2 : tensor<2xi32>):
return %result, %result2 : i32, tensor<2xi32>
}
/// Test the compound folding of BranchOp and CondBranchOp.
// CHECK-LABEL: func @cond_br_and_br_folding(
func.func @cond_br_and_br_folding(%a : i32) {
// CHECK-NEXT: return
%false_cond = arith.constant false
%true_cond = arith.constant true
cf.cond_br %true_cond, ^bb2, ^bb1(%a : i32)
^bb1(%x : i32):
cf.cond_br %false_cond, ^bb1(%x : i32), ^bb2
^bb2:
return
}
/// Test that pass-through successors of CondBranchOp get folded.
// CHECK-LABEL: func @cond_br_passthrough(
// CHECK-SAME: %[[ARG0:.*]]: i32, %[[ARG1:.*]]: i32, %[[ARG2:.*]]: i32, %[[COND:.*]]: i1
func.func @cond_br_passthrough(%arg0 : i32, %arg1 : i32, %arg2 : i32, %cond : i1) -> (i32, i32) {
// CHECK: %[[RES:.*]] = arith.select %[[COND]], %[[ARG0]], %[[ARG2]]
// CHECK: %[[RES2:.*]] = arith.select %[[COND]], %[[ARG1]], %[[ARG2]]
// CHECK: return %[[RES]], %[[RES2]]
cf.cond_br %cond, ^bb1(%arg0 : i32), ^bb2(%arg2, %arg2 : i32, i32)
^bb1(%arg3: i32):
cf.br ^bb2(%arg3, %arg1 : i32, i32)
^bb2(%arg4: i32, %arg5: i32):
return %arg4, %arg5 : i32, i32
}
/// Test the failure modes of collapsing CondBranchOp pass-throughs successors.
// CHECK-LABEL: func @cond_br_pass_through_fail(
func.func @cond_br_pass_through_fail(%cond : i1) {
// CHECK: cf.cond_br %{{.*}}, ^bb1, ^bb2
cf.cond_br %cond, ^bb1, ^bb2
^bb1:
// CHECK: ^bb1:
// CHECK: "foo.op"
// CHECK: cf.br ^bb2
// Successors can't be collapsed if they contain other operations.
"foo.op"() : () -> ()
cf.br ^bb2
^bb2:
return
}
/// Test the folding of SwitchOp
// CHECK-LABEL: func @switch_only_default(
// CHECK-SAME: %[[FLAG:[a-zA-Z0-9_]+]]
// CHECK-SAME: %[[CASE_OPERAND_0:[a-zA-Z0-9_]+]]
func.func @switch_only_default(%flag : i32, %caseOperand0 : f32) {
// add predecessors for all blocks to avoid other canonicalizations.
"foo.pred"() [^bb1, ^bb2] : () -> ()
^bb1:
// CHECK-NOT: cf.switch
// CHECK: cf.br ^[[BB2:[a-zA-Z0-9_]+]](%[[CASE_OPERAND_0]]
cf.switch %flag : i32, [
default: ^bb2(%caseOperand0 : f32)
]
// CHECK: ^[[BB2]]({{.*}}):
^bb2(%bb2Arg : f32):
// CHECK-NEXT: "foo.bb2Terminator"
"foo.bb2Terminator"(%bb2Arg) : (f32) -> ()
}
// CHECK-LABEL: func @switch_case_matching_default(
// CHECK-SAME: %[[FLAG:[a-zA-Z0-9_]+]]
// CHECK-SAME: %[[CASE_OPERAND_0:[a-zA-Z0-9_]+]]
// CHECK-SAME: %[[CASE_OPERAND_1:[a-zA-Z0-9_]+]]
func.func @switch_case_matching_default(%flag : i32, %caseOperand0 : f32, %caseOperand1 : f32) {
// add predecessors for all blocks to avoid other canonicalizations.
"foo.pred"() [^bb1, ^bb2, ^bb3] : () -> ()
^bb1:
// CHECK: cf.switch %[[FLAG]]
// CHECK-NEXT: default: ^[[BB1:.+]](%[[CASE_OPERAND_0]] : f32)
// CHECK-NEXT: 10: ^[[BB2:.+]](%[[CASE_OPERAND_1]] : f32)
// CHECK-NEXT: ]
cf.switch %flag : i32, [
default: ^bb2(%caseOperand0 : f32),
42: ^bb2(%caseOperand0 : f32),
10: ^bb3(%caseOperand1 : f32),
17: ^bb2(%caseOperand0 : f32)
]
^bb2(%bb2Arg : f32):
"foo.bb2Terminator"(%bb2Arg) : (f32) -> ()
^bb3(%bb3Arg : f32):
"foo.bb3Terminator"(%bb3Arg) : (f32) -> ()
}
// CHECK-LABEL: func @switch_on_const_no_match(
// CHECK-SAME: %[[CASE_OPERAND_0:[a-zA-Z0-9_]+]]
// CHECK-SAME: %[[CASE_OPERAND_1:[a-zA-Z0-9_]+]]
// CHECK-SAME: %[[CASE_OPERAND_2:[a-zA-Z0-9_]+]]
func.func @switch_on_const_no_match(%caseOperand0 : f32, %caseOperand1 : f32, %caseOperand2 : f32) {
// add predecessors for all blocks to avoid other canonicalizations.
"foo.pred"() [^bb1, ^bb2, ^bb3, ^bb4] : () -> ()
^bb1:
// CHECK-NOT: cf.switch
// CHECK: cf.br ^[[BB2:[a-zA-Z0-9_]+]](%[[CASE_OPERAND_0]]
%c0_i32 = arith.constant 0 : i32
cf.switch %c0_i32 : i32, [
default: ^bb2(%caseOperand0 : f32),
-1: ^bb3(%caseOperand1 : f32),
1: ^bb4(%caseOperand2 : f32)
]
// CHECK: ^[[BB2]]({{.*}}):
// CHECK-NEXT: "foo.bb2Terminator"
^bb2(%bb2Arg : f32):
"foo.bb2Terminator"(%bb2Arg) : (f32) -> ()
^bb3(%bb3Arg : f32):
"foo.bb3Terminator"(%bb3Arg) : (f32) -> ()
^bb4(%bb4Arg : f32):
"foo.bb4Terminator"(%bb4Arg) : (f32) -> ()
}
// CHECK-LABEL: func @switch_on_const_with_match(
// CHECK-SAME: %[[CASE_OPERAND_0:[a-zA-Z0-9_]+]]
// CHECK-SAME: %[[CASE_OPERAND_1:[a-zA-Z0-9_]+]]
// CHECK-SAME: %[[CASE_OPERAND_2:[a-zA-Z0-9_]+]]
func.func @switch_on_const_with_match(%caseOperand0 : f32, %caseOperand1 : f32, %caseOperand2 : f32) {
// add predecessors for all blocks to avoid other canonicalizations.
"foo.pred"() [^bb1, ^bb2, ^bb3, ^bb4] : () -> ()
^bb1:
// CHECK-NOT: cf.switch
// CHECK: cf.br ^[[BB4:[a-zA-Z0-9_]+]](%[[CASE_OPERAND_2]]
%c0_i32 = arith.constant 1 : i32
cf.switch %c0_i32 : i32, [
default: ^bb2(%caseOperand0 : f32),
-1: ^bb3(%caseOperand1 : f32),
1: ^bb4(%caseOperand2 : f32)
]
^bb2(%bb2Arg : f32):
"foo.bb2Terminator"(%bb2Arg) : (f32) -> ()
^bb3(%bb3Arg : f32):
"foo.bb3Terminator"(%bb3Arg) : (f32) -> ()
// CHECK: ^[[BB4]]({{.*}}):
// CHECK-NEXT: "foo.bb4Terminator"
^bb4(%bb4Arg : f32):
"foo.bb4Terminator"(%bb4Arg) : (f32) -> ()
}
// CHECK-LABEL: func @switch_passthrough(
// CHECK-SAME: %[[FLAG:[a-zA-Z0-9_]+]]
// CHECK-SAME: %[[CASE_OPERAND_0:[a-zA-Z0-9_]+]]
// CHECK-SAME: %[[CASE_OPERAND_1:[a-zA-Z0-9_]+]]
// CHECK-SAME: %[[CASE_OPERAND_2:[a-zA-Z0-9_]+]]
// CHECK-SAME: %[[CASE_OPERAND_3:[a-zA-Z0-9_]+]]
func.func @switch_passthrough(%flag : i32,
%caseOperand0 : f32,
%caseOperand1 : f32,
%caseOperand2 : f32,
%caseOperand3 : f32) {
// add predecessors for all blocks to avoid other canonicalizations.
"foo.pred"() [^bb1, ^bb2, ^bb3, ^bb4, ^bb5, ^bb6] : () -> ()
^bb1:
// CHECK: cf.switch %[[FLAG]]
// CHECK-NEXT: default: ^[[BB5:[a-zA-Z0-9_]+]](%[[CASE_OPERAND_0]]
// CHECK-NEXT: 43: ^[[BB6:[a-zA-Z0-9_]+]](%[[CASE_OPERAND_1]]
// CHECK-NEXT: 44: ^[[BB4:[a-zA-Z0-9_]+]](%[[CASE_OPERAND_2]]
// CHECK-NEXT: ]
cf.switch %flag : i32, [
default: ^bb2(%caseOperand0 : f32),
43: ^bb3(%caseOperand1 : f32),
44: ^bb4(%caseOperand2 : f32)
]
^bb2(%bb2Arg : f32):
cf.br ^bb5(%bb2Arg : f32)
^bb3(%bb3Arg : f32):
cf.br ^bb6(%bb3Arg : f32)
^bb4(%bb4Arg : f32):
"foo.bb4Terminator"(%bb4Arg) : (f32) -> ()
// CHECK: ^[[BB5]]({{.*}}):
// CHECK-NEXT: "foo.bb5Terminator"
^bb5(%bb5Arg : f32):
"foo.bb5Terminator"(%bb5Arg) : (f32) -> ()
// CHECK: ^[[BB6]]({{.*}}):
// CHECK-NEXT: "foo.bb6Terminator"
^bb6(%bb6Arg : f32):
"foo.bb6Terminator"(%bb6Arg) : (f32) -> ()
}
// CHECK-LABEL: func @switch_from_switch_with_same_value_with_match(
// CHECK-SAME: %[[FLAG:[a-zA-Z0-9_]+]]
// CHECK-SAME: %[[CASE_OPERAND_0:[a-zA-Z0-9_]+]]
// CHECK-SAME: %[[CASE_OPERAND_1:[a-zA-Z0-9_]+]]
func.func @switch_from_switch_with_same_value_with_match(%flag : i32, %caseOperand0 : f32, %caseOperand1 : f32) {
// add predecessors for all blocks except ^bb3 to avoid other canonicalizations.
"foo.pred"() [^bb1, ^bb2, ^bb4, ^bb5] : () -> ()
^bb1:
// CHECK: cf.switch %[[FLAG]]
cf.switch %flag : i32, [
default: ^bb2,
42: ^bb3
]
^bb2:
"foo.bb2Terminator"() : () -> ()
^bb3:
// prevent this block from being simplified away
"foo.op"() : () -> ()
// CHECK-NOT: cf.switch %[[FLAG]]
// CHECK: cf.br ^[[BB5:[a-zA-Z0-9_]+]](%[[CASE_OPERAND_1]]
cf.switch %flag : i32, [
default: ^bb4(%caseOperand0 : f32),
42: ^bb5(%caseOperand1 : f32)
]
^bb4(%bb4Arg : f32):
"foo.bb4Terminator"(%bb4Arg) : (f32) -> ()
// CHECK: ^[[BB5]]({{.*}}):
// CHECK-NEXT: "foo.bb5Terminator"
^bb5(%bb5Arg : f32):
"foo.bb5Terminator"(%bb5Arg) : (f32) -> ()
}
// CHECK-LABEL: func @switch_from_switch_with_same_value_no_match(
// CHECK-SAME: %[[FLAG:[a-zA-Z0-9_]+]]
// CHECK-SAME: %[[CASE_OPERAND_0:[a-zA-Z0-9_]+]]
// CHECK-SAME: %[[CASE_OPERAND_1:[a-zA-Z0-9_]+]]
// CHECK-SAME: %[[CASE_OPERAND_2:[a-zA-Z0-9_]+]]
func.func @switch_from_switch_with_same_value_no_match(%flag : i32, %caseOperand0 : f32, %caseOperand1 : f32, %caseOperand2 : f32) {
// add predecessors for all blocks except ^bb3 to avoid other canonicalizations.
"foo.pred"() [^bb1, ^bb2, ^bb4, ^bb5, ^bb6] : () -> ()
^bb1:
// CHECK: cf.switch %[[FLAG]]
cf.switch %flag : i32, [
default: ^bb2,
42: ^bb3
]
^bb2:
"foo.bb2Terminator"() : () -> ()
^bb3:
"foo.op"() : () -> ()
// CHECK-NOT: cf.switch %[[FLAG]]
// CHECK: cf.br ^[[BB4:[a-zA-Z0-9_]+]](%[[CASE_OPERAND_0]]
cf.switch %flag : i32, [
default: ^bb4(%caseOperand0 : f32),
0: ^bb5(%caseOperand1 : f32),
43: ^bb6(%caseOperand2 : f32)
]
// CHECK: ^[[BB4]]({{.*}})
// CHECK-NEXT: "foo.bb4Terminator"
^bb4(%bb4Arg : f32):
"foo.bb4Terminator"(%bb4Arg) : (f32) -> ()
^bb5(%bb5Arg : f32):
"foo.bb5Terminator"(%bb5Arg) : (f32) -> ()
^bb6(%bb6Arg : f32):
"foo.bb6Terminator"(%bb6Arg) : (f32) -> ()
}
// CHECK-LABEL: func @switch_from_switch_default_with_same_value(
// CHECK-SAME: %[[FLAG:[a-zA-Z0-9_]+]]
// CHECK-SAME: %[[CASE_OPERAND_0:[a-zA-Z0-9_]+]]
// CHECK-SAME: %[[CASE_OPERAND_1:[a-zA-Z0-9_]+]]
// CHECK-SAME: %[[CASE_OPERAND_2:[a-zA-Z0-9_]+]]
func.func @switch_from_switch_default_with_same_value(%flag : i32, %caseOperand0 : f32, %caseOperand1 : f32, %caseOperand2 : f32) {
// add predecessors for all blocks except ^bb3 to avoid other canonicalizations.
"foo.pred"() [^bb1, ^bb2, ^bb4, ^bb5, ^bb6] : () -> ()
^bb1:
// CHECK: cf.switch %[[FLAG]]
cf.switch %flag : i32, [
default: ^bb3,
42: ^bb2
]
^bb2:
"foo.bb2Terminator"() : () -> ()
^bb3:
"foo.op"() : () -> ()
// CHECK: cf.switch %[[FLAG]]
// CHECK-NEXT: default: ^[[BB4:[a-zA-Z0-9_]+]](%[[CASE_OPERAND_0]]
// CHECK-NEXT: 43: ^[[BB6:[a-zA-Z0-9_]+]](%[[CASE_OPERAND_2]]
// CHECK-NOT: 42
cf.switch %flag : i32, [
default: ^bb4(%caseOperand0 : f32),
42: ^bb5(%caseOperand1 : f32),
43: ^bb6(%caseOperand2 : f32)
]
// CHECK: ^[[BB4]]({{.*}}):
// CHECK-NEXT: "foo.bb4Terminator"
^bb4(%bb4Arg : f32):
"foo.bb4Terminator"(%bb4Arg) : (f32) -> ()
^bb5(%bb5Arg : f32):
"foo.bb5Terminator"(%bb5Arg) : (f32) -> ()
// CHECK: ^[[BB6]]({{.*}}):
// CHECK-NEXT: "foo.bb6Terminator"
^bb6(%bb6Arg : f32):
"foo.bb6Terminator"(%bb6Arg) : (f32) -> ()
}
/// Test folding conditional branches that are successors of conditional
/// branches with the same condition.
// CHECK-LABEL: func @cond_br_from_cond_br_with_same_condition
func.func @cond_br_from_cond_br_with_same_condition(%cond : i1) {
// CHECK: cf.cond_br %{{.*}}, ^bb1, ^bb2
// CHECK: ^bb1:
// CHECK: return
cf.cond_br %cond, ^bb1, ^bb2
^bb1:
cf.cond_br %cond, ^bb3, ^bb2
^bb2:
"foo.terminator"() : () -> ()
^bb3:
return
}
// -----
// Erase assertion if condition is known to be true at compile time.
// CHECK-LABEL: @assert_true
func.func @assert_true() {
// CHECK-NOT: cf.assert
%true = arith.constant true
cf.assert %true, "Computer says no"
return
}
// -----
// Keep assertion if condition unknown at compile time.
// CHECK-LABEL: @cf.assert
// CHECK-SAME: (%[[ARG:.*]]: i1)
func.func @cf.assert(%arg : i1) {
// CHECK: cf.assert %[[ARG]], "Computer says no"
cf.assert %arg, "Computer says no"
return
}
// -----
// CHECK-LABEL: @branchCondProp
// CHECK: %[[trueval:.+]] = arith.constant true
// CHECK: %[[falseval:.+]] = arith.constant false
// CHECK: "test.consumer1"(%[[trueval]]) : (i1) -> ()
// CHECK: "test.consumer2"(%[[falseval]]) : (i1) -> ()
func.func @branchCondProp(%arg0: i1) {
cf.cond_br %arg0, ^trueB, ^falseB
^trueB:
"test.consumer1"(%arg0) : (i1) -> ()
cf.br ^exit
^falseB:
"test.consumer2"(%arg0) : (i1) -> ()
cf.br ^exit
^exit:
return
}