; RUN: opt -S -analyze -scalar-evolution < %s | FileCheck %s define void @u_0(i8 %rhs) { ; E.g.: %rhs = 255, %start = 99, backedge taken 156 times entry: %start = add i8 %rhs, 100 br label %loop loop: %iv = phi i8 [ %start, %entry ], [ %iv.inc, %loop ] %iv.inc = add nuw i8 %iv, 1 ;; Note: this never unsigned-wraps %iv.cmp = icmp ult i8 %iv, %rhs br i1 %iv.cmp, label %loop, label %leave ; CHECK-LABEL: Determining loop execution counts for: @u_0 ; CHECK-NEXT: Loop %loop: backedge-taken count is (-100 + (-1 * %rhs) + ((100 + %rhs) umax %rhs)) ; CHECK-NEXT: Loop %loop: max backedge-taken count is -100, actual taken count either this or zero. leave: ret void } define void @u_1(i8 %start) { entry: ; E.g.: %start = 99, %rhs = 255, backedge taken 156 times %rhs = add i8 %start, -100 br label %loop loop: %iv = phi i8 [ %start, %entry ], [ %iv.inc, %loop ] %iv.inc = add nuw i8 %iv, 1 ;; Note: this never unsigned-wraps %iv.cmp = icmp ult i8 %iv, %rhs br i1 %iv.cmp, label %loop, label %leave ; CHECK-LABEL: Determining loop execution counts for: @u_1 ; CHECK-NEXT: Loop %loop: backedge-taken count is ((-1 * %start) + ((-100 + %start) umax %start)) ; CHECK-NEXT: Loop %loop: max backedge-taken count is -100, actual taken count either this or zero. leave: ret void } define void @s_0(i8 %rhs) { entry: ; E.g.: %rhs = 127, %start = -29, backedge taken 156 times %start = add i8 %rhs, 100 br label %loop loop: %iv = phi i8 [ %start, %entry ], [ %iv.inc, %loop ] %iv.inc = add nsw i8 %iv, 1 ;; Note: this never signed-wraps %iv.cmp = icmp slt i8 %iv, %rhs br i1 %iv.cmp, label %loop, label %leave ; CHECK-LABEL: Determining loop execution counts for: @s_0 ; CHECK-NEXT: Loop %loop: backedge-taken count is (-100 + (-1 * %rhs) + ((100 + %rhs) smax %rhs)) ; CHECK-NEXT: Loop %loop: max backedge-taken count is -100, actual taken count either this or zero. leave: ret void } define void @s_1(i8 %start) { entry: ; E.g.: start = -29, %rhs = 127, %backedge taken 156 times %rhs = add i8 %start, -100 br label %loop loop: %iv = phi i8 [ %start, %entry ], [ %iv.inc, %loop ] %iv.inc = add nsw i8 %iv, 1 %iv.cmp = icmp slt i8 %iv, %rhs br i1 %iv.cmp, label %loop, label %leave ; CHECK-LABEL: Determining loop execution counts for: @s_1 ; CHECK-NEXT: Loop %loop: backedge-taken count is ((-1 * %start) + ((-100 + %start) smax %start)) ; CHECK-NEXT: Loop %loop: max backedge-taken count is -100, actual taken count either this or zero. leave: ret void }