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// RUN: mlir-opt -allow-unregistered-dialect %s -pass-pipeline="builtin.module(func.func(sccp))" -split-input-file | FileCheck %s
/// Check simple forward constant propagation without any control flow.
// CHECK-LABEL: func @no_control_flow
func.func @no_control_flow(%arg0: i32) -> i32 {
// CHECK: %[[CST:.*]] = arith.constant 1 : i32
// CHECK: return %[[CST]] : i32
%cond = arith.constant true
%cst_1 = arith.constant 1 : i32
%select = arith.select %cond, %cst_1, %arg0 : i32
return %select : i32
}
/// Check that a constant is properly propagated when only one edge of a branch
/// is taken.
// CHECK-LABEL: func @simple_control_flow
func.func @simple_control_flow(%arg0 : i32) -> i32 {
// CHECK: %[[CST:.*]] = arith.constant 1 : i32
%cond = arith.constant true
%1 = arith.constant 1 : i32
cf.cond_br %cond, ^bb1, ^bb2(%arg0 : i32)
^bb1:
cf.br ^bb2(%1 : i32)
^bb2(%arg : i32):
// CHECK: ^bb2(%{{.*}}: i32):
// CHECK: return %[[CST]] : i32
return %arg : i32
}
/// Check that the arguments go to overdefined if the branch cannot detect when
/// a specific successor is taken.
// CHECK-LABEL: func @simple_control_flow_overdefined
func.func @simple_control_flow_overdefined(%arg0 : i32, %arg1 : i1) -> i32 {
%1 = arith.constant 1 : i32
cf.cond_br %arg1, ^bb1, ^bb2(%arg0 : i32)
^bb1:
cf.br ^bb2(%1 : i32)
^bb2(%arg : i32):
// CHECK: ^bb2(%[[ARG:.*]]: i32):
// CHECK: return %[[ARG]] : i32
return %arg : i32
}
/// Check that the arguments go to overdefined if there are conflicting
/// constants.
// CHECK-LABEL: func @simple_control_flow_constant_overdefined
func.func @simple_control_flow_constant_overdefined(%arg0 : i32, %arg1 : i1) -> i32 {
%1 = arith.constant 1 : i32
%2 = arith.constant 2 : i32
cf.cond_br %arg1, ^bb1, ^bb2(%arg0 : i32)
^bb1:
cf.br ^bb2(%2 : i32)
^bb2(%arg : i32):
// CHECK: ^bb2(%[[ARG:.*]]: i32):
// CHECK: return %[[ARG]] : i32
return %arg : i32
}
/// Check that the arguments go to overdefined if the branch is unknown.
// CHECK-LABEL: func @unknown_terminator
func.func @unknown_terminator(%arg0 : i32, %arg1 : i1) -> i32 {
%1 = arith.constant 1 : i32
"foo.cond_br"() [^bb1, ^bb2] : () -> ()
^bb1:
cf.br ^bb2(%1 : i32)
^bb2(%arg : i32):
// CHECK: ^bb2(%[[ARG:.*]]: i32):
// CHECK: return %[[ARG]] : i32
return %arg : i32
}
/// Check that arguments are properly merged across loop-like control flow.
func.func private @ext_cond_fn() -> i1
// CHECK-LABEL: func @simple_loop
func.func @simple_loop(%arg0 : i32, %cond1 : i1) -> i32 {
// CHECK: %[[CST:.*]] = arith.constant 1 : i32
%cst_1 = arith.constant 1 : i32
cf.cond_br %cond1, ^bb1(%cst_1 : i32), ^bb2(%cst_1 : i32)
^bb1(%iv: i32):
// CHECK: ^bb1(%{{.*}}: i32):
// CHECK-NEXT: %[[COND:.*]] = call @ext_cond_fn()
// CHECK-NEXT: cf.cond_br %[[COND]], ^bb1(%[[CST]] : i32), ^bb2(%[[CST]] : i32)
%cst_0 = arith.constant 0 : i32
%res = arith.addi %iv, %cst_0 : i32
%cond2 = call @ext_cond_fn() : () -> i1
cf.cond_br %cond2, ^bb1(%res : i32), ^bb2(%res : i32)
^bb2(%arg : i32):
// CHECK: ^bb2(%{{.*}}: i32):
// CHECK: return %[[CST]] : i32
return %arg : i32
}
/// Test that we can properly propagate within inner control, and in situations
/// where the executable edges within the CFG are sensitive to the current state
/// of the analysis.
// CHECK-LABEL: func @simple_loop_inner_control_flow
func.func @simple_loop_inner_control_flow(%arg0 : i32) -> i32 {
// CHECK-DAG: %[[CST:.*]] = arith.constant 1 : i32
// CHECK-DAG: %[[TRUE:.*]] = arith.constant true
%cst_1 = arith.constant 1 : i32
cf.br ^bb1(%cst_1 : i32)
^bb1(%iv: i32):
%cond2 = call @ext_cond_fn() : () -> i1
cf.cond_br %cond2, ^bb5(%iv : i32), ^bb2
^bb2:
// CHECK: ^bb2:
// CHECK: cf.cond_br %[[TRUE]], ^bb3, ^bb4
%cst_20 = arith.constant 20 : i32
%cond = arith.cmpi ult, %iv, %cst_20 : i32
cf.cond_br %cond, ^bb3, ^bb4
^bb3:
// CHECK: ^bb3:
// CHECK: cf.br ^bb1(%[[CST]] : i32)
%cst_1_2 = arith.constant 1 : i32
cf.br ^bb1(%cst_1_2 : i32)
^bb4:
%iv_inc = arith.addi %iv, %cst_1 : i32
cf.br ^bb1(%iv_inc : i32)
^bb5(%result: i32):
// CHECK: ^bb5(%{{.*}}: i32):
// CHECK: return %[[CST]] : i32
return %result : i32
}
/// Check that arguments go to overdefined when loop backedges produce a
/// conflicting value.
func.func private @ext_cond_and_value_fn() -> (i1, i32)
// CHECK-LABEL: func @simple_loop_overdefined
func.func @simple_loop_overdefined(%arg0 : i32, %cond1 : i1) -> i32 {
%cst_1 = arith.constant 1 : i32
cf.cond_br %cond1, ^bb1(%cst_1 : i32), ^bb2(%cst_1 : i32)
^bb1(%iv: i32):
%cond2, %res = call @ext_cond_and_value_fn() : () -> (i1, i32)
cf.cond_br %cond2, ^bb1(%res : i32), ^bb2(%res : i32)
^bb2(%arg : i32):
// CHECK: ^bb2(%[[ARG:.*]]: i32):
// CHECK: return %[[ARG]] : i32
return %arg : i32
}
// Check that we reprocess executable edges when information changes.
// CHECK-LABEL: func @recheck_executable_edge
func.func @recheck_executable_edge(%cond0: i1) -> (i1, i1) {
%true = arith.constant true
%false = arith.constant false
cf.cond_br %cond0, ^bb_1a, ^bb2(%false : i1)
^bb_1a:
cf.br ^bb2(%true : i1)
^bb2(%x: i1):
// CHECK: ^bb2(%[[X:.*]]: i1):
cf.br ^bb3(%x : i1)
^bb3(%y: i1):
// CHECK: ^bb3(%[[Y:.*]]: i1):
// CHECK: return %[[X]], %[[Y]]
return %x, %y : i1, i1
}
// CHECK-LABEL: func @simple_produced_operand
func.func @simple_produced_operand() -> (i32, i32) {
// CHECK: %[[ONE:.*]] = arith.constant 1
%1 = arith.constant 1 : i32
"test.internal_br"(%1) [^bb1, ^bb2] {
operandSegmentSizes = array<i32: 0, 1>
} : (i32) -> ()
^bb1:
cf.br ^bb2(%1, %1 : i32, i32)
^bb2(%arg1 : i32, %arg2 : i32):
// CHECK: ^bb2(%[[ARG:.*]]: i32, %{{.*}}: i32):
// CHECK: return %[[ARG]], %[[ONE]] : i32, i32
return %arg1, %arg2 : i32, i32
}
// CHECK-LABEL: inplace_fold
func.func @inplace_fold() -> (i32) {
%0 = "test.op_in_place_fold_success"() : () -> i1
%1 = arith.constant 5 : i32
cf.cond_br %0, ^a, ^b
^a:
// CHECK-NOT: addi
%3 = arith.addi %1, %1 : i32
return %3 : i32
^b:
return %1 : i32
}
// CHECK-LABEL: op_with_region
func.func @op_with_region() -> (i32) {
%0 = "test.op_with_region"() ({}) : () -> i1
%1 = arith.constant 5 : i32
cf.cond_br %0, ^a, ^b
^a:
// CHECK-NOT: addi
%3 = arith.addi %1, %1 : i32
return %3 : i32
^b:
return %1 : i32
}
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