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|
; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt -passes=constraint-elimination -S %s | FileCheck %s
; Here we can remove range check because:
; length >= min_length (from entry)
; idx < min_length (from in_bounds check)
; therefore, idx < length is trivially true.
define i32 @test_01(ptr %p, ptr %array, i32 %min_length) {
; CHECK-LABEL: @test_01(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[IV:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[BACKEDGE:%.*]] ]
; CHECK-NEXT: [[ELEM_PTR:%.*]] = getelementptr i32, ptr [[P:%.*]], i32 [[IV]]
; CHECK-NEXT: [[IDX:%.*]] = load i32, ptr [[ELEM_PTR]], align 4
; CHECK-NEXT: [[IN_BOUNDS:%.*]] = icmp ult i32 [[IDX]], [[MIN_LENGTH:%.*]]
; CHECK-NEXT: br i1 [[IN_BOUNDS]], label [[RANGE_CHECK_BLOCK:%.*]], label [[OUT_OF_BOUNDS:%.*]]
; CHECK: range_check_block:
; CHECK-NEXT: [[RANGE_CHECK:%.*]] = icmp ult i32 [[IDX]], [[MIN_LENGTH]]
; CHECK-NEXT: br i1 true, label [[BACKEDGE]], label [[RANGE_CHECK_FAILED:%.*]]
; CHECK: backedge:
; CHECK-NEXT: [[ARR_PTR:%.*]] = getelementptr i32, ptr [[ARRAY:%.*]], i32 [[IDX]]
; CHECK-NEXT: store i32 [[IV]], ptr [[ARR_PTR]], align 4
; CHECK-NEXT: [[IV_NEXT]] = add i32 [[IV]], 1
; CHECK-NEXT: [[LOOP_COND:%.*]] = call i1 @cond()
; CHECK-NEXT: br i1 [[LOOP_COND]], label [[LOOP]], label [[EXIT:%.*]]
; CHECK: exit:
; CHECK-NEXT: [[IV_LCSSA:%.*]] = phi i32 [ [[IV]], [[BACKEDGE]] ]
; CHECK-NEXT: ret i32 [[IV_LCSSA]]
; CHECK: out_of_bounds:
; CHECK-NEXT: ret i32 -1
; CHECK: range_check_failed:
; CHECK-NEXT: [[IV_LCSSA_RC:%.*]] = phi i32 [ [[IV]], [[RANGE_CHECK_BLOCK]] ]
; CHECK-NEXT: call void @failed_range_check(i32 [[IV_LCSSA_RC]])
; CHECK-NEXT: unreachable
;
entry:
br label %loop
loop: ; preds = %backedge, %entry
%iv = phi i32 [ 0, %entry ], [ %iv.next, %backedge ]
%elem_ptr = getelementptr i32, ptr %p, i32 %iv
%idx = load i32, ptr %elem_ptr, align 4
%in_bounds = icmp ult i32 %idx, %min_length
br i1 %in_bounds, label %range_check_block, label %out_of_bounds
range_check_block: ; preds = %loop
%range_check = icmp ult i32 %idx, %min_length
br i1 %range_check, label %backedge, label %range_check_failed
backedge: ; preds = %range_check_block
%arr_ptr = getelementptr i32, ptr %array, i32 %idx
store i32 %iv, ptr %arr_ptr, align 4
%iv.next = add i32 %iv, 1
%loop_cond = call i1 @cond()
br i1 %loop_cond, label %loop, label %exit
exit: ; preds = %backedge
%iv.lcssa = phi i32 [ %iv, %backedge ]
ret i32 %iv.lcssa
out_of_bounds: ; preds = %loop
ret i32 -1
range_check_failed: ; preds = %range_check_block
%iv.lcssa.rc = phi i32 [ %iv, %range_check_block ]
call void @failed_range_check(i32 %iv.lcssa.rc)
unreachable
}
define i32 @test_02(ptr %p, ptr %array, i32 %length, i32 %min_length) {
; CHECK-LABEL: @test_02(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[LENGTH_CHECK:%.*]] = icmp uge i32 [[LENGTH:%.*]], [[MIN_LENGTH:%.*]]
; CHECK-NEXT: br i1 [[LENGTH_CHECK]], label [[LOOP:%.*]], label [[FAILED:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[IV:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[IV_NEXT:%.*]], [[BACKEDGE:%.*]] ]
; CHECK-NEXT: [[ELEM_PTR:%.*]] = getelementptr i32, ptr [[P:%.*]], i32 [[IV]]
; CHECK-NEXT: [[IDX:%.*]] = load i32, ptr [[ELEM_PTR]], align 4
; CHECK-NEXT: [[IN_BOUNDS:%.*]] = icmp ult i32 [[IDX]], [[MIN_LENGTH]]
; CHECK-NEXT: br i1 [[IN_BOUNDS]], label [[RANGE_CHECK_BLOCK:%.*]], label [[OUT_OF_BOUNDS:%.*]]
; CHECK: range_check_block:
; CHECK-NEXT: [[RANGE_CHECK:%.*]] = icmp ult i32 [[IDX]], [[LENGTH]]
; CHECK-NEXT: br i1 true, label [[BACKEDGE]], label [[RANGE_CHECK_FAILED:%.*]]
; CHECK: backedge:
; CHECK-NEXT: [[ARR_PTR:%.*]] = getelementptr i32, ptr [[ARRAY:%.*]], i32 [[IDX]]
; CHECK-NEXT: store i32 [[IV]], ptr [[ARR_PTR]], align 4
; CHECK-NEXT: [[IV_NEXT]] = add i32 [[IV]], 1
; CHECK-NEXT: [[LOOP_COND:%.*]] = call i1 @cond()
; CHECK-NEXT: br i1 [[LOOP_COND]], label [[LOOP]], label [[EXIT:%.*]]
; CHECK: exit:
; CHECK-NEXT: [[IV_LCSSA:%.*]] = phi i32 [ [[IV]], [[BACKEDGE]] ]
; CHECK-NEXT: ret i32 [[IV_LCSSA]]
; CHECK: failed:
; CHECK-NEXT: unreachable
; CHECK: out_of_bounds:
; CHECK-NEXT: ret i32 -1
; CHECK: range_check_failed:
; CHECK-NEXT: [[IV_LCSSA_RC:%.*]] = phi i32 [ [[IV]], [[RANGE_CHECK_BLOCK]] ]
; CHECK-NEXT: call void @failed_range_check(i32 [[IV_LCSSA_RC]])
; CHECK-NEXT: unreachable
;
entry:
%length_check = icmp uge i32 %length, %min_length
br i1 %length_check, label %loop, label %failed
loop: ; preds = %backedge, %entry
%iv = phi i32 [ 0, %entry ], [ %iv.next, %backedge ]
%elem_ptr = getelementptr i32, ptr %p, i32 %iv
%idx = load i32, ptr %elem_ptr, align 4
%in_bounds = icmp ult i32 %idx, %min_length
br i1 %in_bounds, label %range_check_block, label %out_of_bounds
range_check_block: ; preds = %loop
%range_check = icmp ult i32 %idx, %length
br i1 %range_check, label %backedge, label %range_check_failed
backedge: ; preds = %range_check_block
%arr_ptr = getelementptr i32, ptr %array, i32 %idx
store i32 %iv, ptr %arr_ptr, align 4
%iv.next = add i32 %iv, 1
%loop_cond = call i1 @cond()
br i1 %loop_cond, label %loop, label %exit
exit: ; preds = %backedge
%iv.lcssa = phi i32 [ %iv, %backedge ]
ret i32 %iv.lcssa
failed: ; preds = %entry
unreachable
out_of_bounds: ; preds = %loop
ret i32 -1
range_check_failed: ; preds = %range_check_block
%iv.lcssa.rc = phi i32 [ %iv, %range_check_block ]
call void @failed_range_check(i32 %iv.lcssa.rc)
unreachable
}
declare i1 @cond()
declare void @failed_range_check(i32)
|
