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|
// RUN: mlir-opt -allow-unregistered-dialect -loop-coalescing %s | FileCheck %s
// CHECK-LABEL: @one_3d_nest
func @one_3d_nest() {
// Capture original bounds. Note that for zero-based step-one loops, the
// upper bound is also the number of iterations.
// CHECK: %[[orig_lb:.*]] = constant 0
// CHECK: %[[orig_step:.*]] = constant 1
// CHECK: %[[orig_ub_k:.*]] = constant 3
// CHECK: %[[orig_ub_i:.*]] = constant 42
// CHECK: %[[orig_ub_j:.*]] = constant 56
%c0 = constant 0 : index
%c1 = constant 1 : index
%c2 = constant 2 : index
%c3 = constant 3 : index
%c42 = constant 42 : index
%c56 = constant 56 : index
// The range of the new scf.
// CHECK: %[[partial_range:.*]] = muli %[[orig_ub_i]], %[[orig_ub_j]]
// CHECK-NEXT:%[[range:.*]] = muli %[[partial_range]], %[[orig_ub_k]]
// Updated loop bounds.
// CHECK: scf.for %[[i:.*]] = %[[orig_lb]] to %[[range]] step %[[orig_step]]
scf.for %i = %c0 to %c42 step %c1 {
// Inner loops must have been removed.
// CHECK-NOT: scf.for
// Reconstruct original IVs from the linearized one.
// CHECK: %[[orig_k:.*]] = remi_signed %[[i]], %[[orig_ub_k]]
// CHECK: %[[div:.*]] = divi_signed %[[i]], %[[orig_ub_k]]
// CHECK: %[[orig_j:.*]] = remi_signed %[[div]], %[[orig_ub_j]]
// CHECK: %[[orig_i:.*]] = divi_signed %[[div]], %[[orig_ub_j]]
scf.for %j = %c0 to %c56 step %c1 {
scf.for %k = %c0 to %c3 step %c1 {
// CHECK: "use"(%[[orig_i]], %[[orig_j]], %[[orig_k]])
"use"(%i, %j, %k) : (index, index, index) -> ()
}
}
}
return
}
// Check that there is no chasing the replacement of value uses by ensuring
// multiple uses of loop induction variables get rewritten to the same values.
// CHECK-LABEL: @multi_use
func @multi_use() {
%c0 = constant 0 : index
%c1 = constant 1 : index
%c10 = constant 10 : index
// CHECK: scf.for %[[iv:.*]] =
scf.for %i = %c1 to %c10 step %c1 {
scf.for %j = %c1 to %c10 step %c1 {
scf.for %k = %c1 to %c10 step %c1 {
// CHECK: %[[k_unshifted:.*]] = remi_signed %[[iv]], %[[k_extent:.*]]
// CHECK: %[[ij:.*]] = divi_signed %[[iv]], %[[k_extent]]
// CHECK: %[[j_unshifted:.*]] = remi_signed %[[ij]], %[[j_extent:.*]]
// CHECK: %[[i_unshifted:.*]] = divi_signed %[[ij]], %[[j_extent]]
// CHECK: %[[k:.*]] = addi %[[k_unshifted]]
// CHECK: %[[j:.*]] = addi %[[j_unshifted]]
// CHECK: %[[i:.*]] = addi %[[i_unshifted]]
// CHECK: "use1"(%[[i]], %[[j]], %[[k]])
"use1"(%i,%j,%k) : (index,index,index) -> ()
// CHECK: "use2"(%[[i]], %[[k]], %[[j]])
"use2"(%i,%k,%j) : (index,index,index) -> ()
// CHECK: "use3"(%[[k]], %[[j]], %[[i]])
"use3"(%k,%j,%i) : (index,index,index) -> ()
}
}
}
return
}
func @unnormalized_loops() {
// CHECK: %[[orig_step_i:.*]] = constant 2
// CHECK: %[[orig_step_j:.*]] = constant 3
// CHECK: %[[orig_lb_i:.*]] = constant 5
// CHECK: %[[orig_lb_j:.*]] = constant 7
// CHECK: %[[orig_ub_i:.*]] = constant 10
// CHECK: %[[orig_ub_j:.*]] = constant 17
%c2 = constant 2 : index
%c3 = constant 3 : index
%c5 = constant 5 : index
%c7 = constant 7 : index
%c10 = constant 10 : index
%c17 = constant 17 : index
// Number of iterations in the outer scf.
// CHECK: %[[diff_i:.*]] = subi %[[orig_ub_i]], %[[orig_lb_i]]
// CHECK: %[[c1:.*]] = constant 1
// CHECK: %[[step_minus_c1:.*]] = subi %[[orig_step_i]], %[[c1]]
// CHECK: %[[dividend:.*]] = addi %[[diff_i]], %[[step_minus_c1]]
// CHECK: %[[numiter_i:.*]] = divi_signed %[[dividend]], %[[orig_step_i]]
// Normalized lower bound and step for the outer scf.
// CHECK: %[[lb_i:.*]] = constant 0
// CHECK: %[[step_i:.*]] = constant 1
// Number of iterations in the inner loop, the pattern is the same as above,
// only capture the final result.
// CHECK: %[[numiter_j:.*]] = divi_signed {{.*}}, %[[orig_step_j]]
// New bounds of the outer scf.
// CHECK: %[[range:.*]] = muli %[[numiter_i]], %[[numiter_j]]
// CHECK: scf.for %[[i:.*]] = %[[lb_i]] to %[[range]] step %[[step_i]]
scf.for %i = %c5 to %c10 step %c2 {
// The inner loop has been removed.
// CHECK-NOT: scf.for
scf.for %j = %c7 to %c17 step %c3 {
// The IVs are rewritten.
// CHECK: %[[normalized_j:.*]] = remi_signed %[[i]], %[[numiter_j]]
// CHECK: %[[normalized_i:.*]] = divi_signed %[[i]], %[[numiter_j]]
// CHECK: %[[scaled_j:.*]] = muli %[[normalized_j]], %[[orig_step_j]]
// CHECK: %[[orig_j:.*]] = addi %[[scaled_j]], %[[orig_lb_j]]
// CHECK: %[[scaled_i:.*]] = muli %[[normalized_i]], %[[orig_step_i]]
// CHECK: %[[orig_i:.*]] = addi %[[scaled_i]], %[[orig_lb_i]]
// CHECK: "use"(%[[orig_i]], %[[orig_j]])
"use"(%i, %j) : (index, index) -> ()
}
}
return
}
// Check with parametric loop bounds and steps, capture the bounds here.
// CHECK-LABEL: @parametric
// CHECK-SAME: %[[orig_lb1:[A-Za-z0-9]+]]:
// CHECK-SAME: %[[orig_ub1:[A-Za-z0-9]+]]:
// CHECK-SAME: %[[orig_step1:[A-Za-z0-9]+]]:
// CHECK-SAME: %[[orig_lb2:[A-Za-z0-9]+]]:
// CHECK-SAME: %[[orig_ub2:[A-Za-z0-9]+]]:
// CHECK-SAME: %[[orig_step2:[A-Za-z0-9]+]]:
func @parametric(%lb1 : index, %ub1 : index, %step1 : index,
%lb2 : index, %ub2 : index, %step2 : index) {
// Compute the number of iterations for each of the loops and the total
// number of iterations.
// CHECK: %[[range1:.*]] = subi %[[orig_ub1]], %[[orig_lb1]]
// CHECK: %[[orig_step1_minus_1:.*]] = subi %[[orig_step1]], %c1
// CHECK: %[[dividend1:.*]] = addi %[[range1]], %[[orig_step1_minus_1]]
// CHECK: %[[numiter1:.*]] = divi_signed %[[dividend1]], %[[orig_step1]]
// CHECK: %[[range2:.*]] = subi %[[orig_ub2]], %[[orig_lb2]]
// CHECK: %[[orig_step2_minus_1:.*]] = subi %arg5, %c1
// CHECK: %[[dividend2:.*]] = addi %[[range2]], %[[orig_step2_minus_1]]
// CHECK: %[[numiter2:.*]] = divi_signed %[[dividend2]], %[[orig_step2]]
// CHECK: %[[range:.*]] = muli %[[numiter1]], %[[numiter2]] : index
// Check that the outer loop is updated.
// CHECK: scf.for %[[i:.*]] = %c0{{.*}} to %[[range]] step %c1
scf.for %i = %lb1 to %ub1 step %step1 {
// Check that the inner loop is removed.
// CHECK-NOT: scf.for
scf.for %j = %lb2 to %ub2 step %step2 {
// Remapping of the induction variables.
// CHECK: %[[normalized_j:.*]] = remi_signed %[[i]], %[[numiter2]] : index
// CHECK: %[[normalized_i:.*]] = divi_signed %[[i]], %[[numiter2]] : index
// CHECK: %[[scaled_j:.*]] = muli %[[normalized_j]], %[[orig_step2]]
// CHECK: %[[orig_j:.*]] = addi %[[scaled_j]], %[[orig_lb2]]
// CHECK: %[[scaled_i:.*]] = muli %[[normalized_i]], %[[orig_step1]]
// CHECK: %[[orig_i:.*]] = addi %[[scaled_i]], %[[orig_lb1]]
// CHECK: "foo"(%[[orig_i]], %[[orig_j]])
"foo"(%i, %j) : (index, index) -> ()
}
}
return
}
// CHECK-LABEL: @two_bands
func @two_bands() {
%c0 = constant 0 : index
%c1 = constant 1 : index
%c10 = constant 10 : index
// CHECK: %[[outer_range:.*]] = muli
// CHECK: scf.for %{{.*}} = %{{.*}} to %[[outer_range]]
scf.for %i = %c0 to %c10 step %c1 {
// Check that the "j" loop was removed and that the inner loops were
// coalesced as well. The preparation step for coalescing will inject the
// subtraction operation unlike the IV remapping.
// CHECK-NOT: scf.for
// CHECK: subi
scf.for %j = %c0 to %c10 step %c1 {
// The inner pair of loops is coalesced separately.
// CHECK: scf.for
scf.for %k = %i to %j step %c1 {
// CHECK_NOT: scf.for
scf.for %l = %i to %j step %c1 {
"foo"() : () -> ()
}
}
}
}
return
}
|
