| ; These tests ensure that we can compute the trip count of various forms of |
| ; loops. If the trip count of the loop is computable, then we will know what |
| ; the exit value of the loop will be for some value, allowing us to substitute |
| ; it directly into users outside of the loop, making the loop dead. |
| ; |
| ; RUN: llvm-as < %s | opt -indvars -adce -simplifycfg | llvm-dis | not grep br |
| |
| int %linear_setne() { ;; for (i = 0; i != 100; ++i) |
| entry: |
| br label %loop |
| loop: |
| %i = phi int [ 0, %entry ], [ %i.next, %loop ] |
| %i.next = add int %i, 1 |
| %c = setne int %i, 100 |
| br bool %c, label %loop, label %loopexit |
| loopexit: |
| ret int %i |
| } |
| |
| int %linear_setne_2() { ;; for (i = 0; i != 100; i += 2) |
| entry: |
| br label %loop |
| loop: |
| %i = phi int [ 0, %entry ], [ %i.next, %loop ] |
| %i.next = add int %i, 2 |
| %c = setne int %i, 100 |
| br bool %c, label %loop, label %loopexit |
| loopexit: |
| ret int %i |
| } |
| |
| |
| int %linear_setne_overflow() { ;; for (i = 1024; i != 0; i += 1024) |
| entry: |
| br label %loop |
| loop: |
| %i = phi int [ 1024, %entry ], [ %i.next, %loop ] |
| %i.next = add int %i, 1024 |
| %c = setne int %i, 0 |
| br bool %c, label %loop, label %loopexit |
| loopexit: |
| ret int %i |
| } |
| |
| int %linear_setlt() { ;; for (i = 0; i < 100; ++i) |
| entry: |
| br label %loop |
| loop: |
| %i = phi int [ 0, %entry ], [ %i.next, %loop ] |
| %i.next = add int %i, 1 |
| %c = setlt int %i, 100 |
| br bool %c, label %loop, label %loopexit |
| loopexit: |
| ret int %i |
| } |
| |
| int %quadratic_setlt() { ;; for (i = 7; i*i < 1000; i+=3) |
| entry: |
| br label %loop |
| loop: |
| %i = phi int [ 7, %entry ], [ %i.next, %loop ] |
| %i.next = add int %i, 3 |
| %i2 = mul int %i, %i |
| %c = setlt int %i2, 1000 |
| br bool %c, label %loop, label %loopexit |
| loopexit: |
| ret int %i |
| } |
| |
| ;; Chained loop test - The exit value of the second loop depends on the exit |
| ;; value of the first being computed. |
| int %chained() { |
| entry: |
| br label %loop |
| loop: ;; for (i = 0; i != 100; ++i) |
| %i = phi int [ 0, %entry ], [ %i.next, %loop ] |
| %i.next = add int %i, 1 |
| %c = setne int %i, 100 |
| br bool %c, label %loop, label %loopexit |
| loopexit: |
| br label %loop2 |
| loop2: ;; for (j = i; j != 200; ++j) |
| %j = phi int [ %i, %loopexit ], [ %j.next, %loop2 ] |
| %j.next = add int %j, 1 |
| %c2 = setne int %j, 200 |
| br bool %c2, label %loop2, label %loopexit2 |
| loopexit2: |
| ret int %j |
| } |
| |