1// RUN: mlir-opt -allow-unregistered-dialect %s -pass-pipeline="func(sccp)" -split-input-file | FileCheck %s 2 3/// Check that a constant is properly propagated when only one edge is taken. 4 5// CHECK-LABEL: func @simple( 6func @simple(%arg0 : i32) -> i32 { 7 // CHECK: %[[CST:.*]] = constant 1 : i32 8 // CHECK-NOT: scf.if 9 // CHECK: return %[[CST]] : i32 10 11 %cond = constant true 12 %res = scf.if %cond -> (i32) { 13 %1 = constant 1 : i32 14 scf.yield %1 : i32 15 } else { 16 scf.yield %arg0 : i32 17 } 18 return %res : i32 19} 20 21/// Check that a constant is properly propagated when both edges produce the 22/// same value. 23 24// CHECK-LABEL: func @simple_both_same( 25func @simple_both_same(%cond : i1) -> i32 { 26 // CHECK: %[[CST:.*]] = constant 1 : i32 27 // CHECK-NOT: scf.if 28 // CHECK: return %[[CST]] : i32 29 30 %res = scf.if %cond -> (i32) { 31 %1 = constant 1 : i32 32 scf.yield %1 : i32 33 } else { 34 %2 = constant 1 : i32 35 scf.yield %2 : i32 36 } 37 return %res : i32 38} 39 40/// Check that the arguments go to overdefined if the branch cannot detect when 41/// a specific successor is taken. 42 43// CHECK-LABEL: func @overdefined_unknown_condition( 44func @overdefined_unknown_condition(%cond : i1, %arg0 : i32) -> i32 { 45 // CHECK: %[[RES:.*]] = scf.if 46 // CHECK: return %[[RES]] : i32 47 48 %res = scf.if %cond -> (i32) { 49 %1 = constant 1 : i32 50 scf.yield %1 : i32 51 } else { 52 scf.yield %arg0 : i32 53 } 54 return %res : i32 55} 56 57/// Check that the arguments go to overdefined if there are conflicting 58/// constants. 59 60// CHECK-LABEL: func @overdefined_different_constants( 61func @overdefined_different_constants(%cond : i1) -> i32 { 62 // CHECK: %[[RES:.*]] = scf.if 63 // CHECK: return %[[RES]] : i32 64 65 %res = scf.if %cond -> (i32) { 66 %1 = constant 1 : i32 67 scf.yield %1 : i32 68 } else { 69 %2 = constant 2 : i32 70 scf.yield %2 : i32 71 } 72 return %res : i32 73} 74 75/// Check that arguments are properly merged across loop-like control flow. 76 77// CHECK-LABEL: func @simple_loop( 78func @simple_loop(%arg0 : index, %arg1 : index, %arg2 : index) -> i32 { 79 // CHECK: %[[CST:.*]] = constant 0 : i32 80 // CHECK-NOT: scf.for 81 // CHECK: return %[[CST]] : i32 82 83 %s0 = constant 0 : i32 84 %result = scf.for %i0 = %arg0 to %arg1 step %arg2 iter_args(%si = %s0) -> (i32) { 85 %sn = addi %si, %si : i32 86 scf.yield %sn : i32 87 } 88 return %result : i32 89} 90 91/// Check that arguments go to overdefined when loop backedges produce a 92/// conflicting value. 93 94// CHECK-LABEL: func @loop_overdefined( 95func @loop_overdefined(%arg0 : index, %arg1 : index, %arg2 : index) -> i32 { 96 // CHECK: %[[RES:.*]] = scf.for 97 // CHECK: return %[[RES]] : i32 98 99 %s0 = constant 1 : i32 100 %result = scf.for %i0 = %arg0 to %arg1 step %arg2 iter_args(%si = %s0) -> (i32) { 101 %sn = addi %si, %si : i32 102 scf.yield %sn : i32 103 } 104 return %result : i32 105} 106 107/// Test that we can properly propagate within inner control, and in situations 108/// where the executable edges within the CFG are sensitive to the current state 109/// of the analysis. 110 111// CHECK-LABEL: func @loop_inner_control_flow( 112func @loop_inner_control_flow(%arg0 : index, %arg1 : index, %arg2 : index) -> i32 { 113 // CHECK: %[[CST:.*]] = constant 1 : i32 114 // CHECK-NOT: scf.for 115 // CHECK-NOT: scf.if 116 // CHECK: return %[[CST]] : i32 117 118 %cst_1 = constant 1 : i32 119 %result = scf.for %i0 = %arg0 to %arg1 step %arg2 iter_args(%si = %cst_1) -> (i32) { 120 %cst_20 = constant 20 : i32 121 %cond = cmpi "ult", %si, %cst_20 : i32 122 %inner_res = scf.if %cond -> (i32) { 123 %1 = constant 1 : i32 124 scf.yield %1 : i32 125 } else { 126 %si_inc = addi %si, %cst_1 : i32 127 scf.yield %si_inc : i32 128 } 129 scf.yield %inner_res : i32 130 } 131 return %result : i32 132} 133