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; Test that we can evaluate the exit values of various expression types. Since
; these loops all have predictable exit values we can replace the use outside
; of the loop with a closed-form computation, making the loop dead.
;
; RUN: llvm-upgrade < %s | llvm-as | opt -indvars -adce -simplifycfg | llvm-dis | not grep br
int %polynomial_constant() {
br label %Loop
Loop:
%A1 = phi int [0, %0], [%A2, %Loop]
%B1 = phi int [0, %0], [%B2, %Loop]
%A2 = add int %A1, 1
%B2 = add int %B1, %A1
%C = seteq int %A1, 1000
br bool %C, label %Out, label %Loop
Out:
ret int %B2
}
int %NSquare(int %N) {
br label %Loop
Loop:
%X = phi int [0, %0], [%X2, %Loop]
%X2 = add int %X, 1
%c = seteq int %X, %N
br bool %c, label %Out, label %Loop
Out:
%Y = mul int %X, %X
ret int %Y
}
int %NSquareOver2(int %N) {
br label %Loop
Loop:
%X = phi int [0, %0], [%X2, %Loop]
%Y = phi int [15, %0], [%Y2, %Loop] ;; include offset of 15 for yuks
%Y2 = add int %Y, %X
%X2 = add int %X, 1
%c = seteq int %X, %N
br bool %c, label %Out, label %Loop
Out:
ret int %Y2
}
int %strength_reduced() {
br label %Loop
Loop:
%A1 = phi int [0, %0], [%A2, %Loop]
%B1 = phi int [0, %0], [%B2, %Loop]
%A2 = add int %A1, 1
%B2 = add int %B1, %A1
%C = seteq int %A1, 1000
br bool %C, label %Out, label %Loop
Out:
ret int %B2
}
int %chrec_equals() {
entry:
br label %no_exit
no_exit:
%i0 = phi int [ 0, %entry ], [ %i1, %no_exit ]
%ISq = mul int %i0, %i0
%i1 = add int %i0, 1
%tmp.1 = setne int %ISq, 10000 ; while (I*I != 1000)
br bool %tmp.1, label %no_exit, label %loopexit
loopexit:
ret int %i1
}
;; We should recognize B1 as being a recurrence, allowing us to compute the
;; trip count and eliminate the loop.
short %cast_chrec_test() {
br label %Loop
Loop:
%A1 = phi int [0, %0], [%A2, %Loop]
%B1 = cast int %A1 to short
%A2 = add int %A1, 1
%C = seteq short %B1, 1000
br bool %C, label %Out, label %Loop
Out:
ret short %B1
}
uint %linear_div_fold() { ;; for (i = 4; i != 68; i += 8) (exit with i/2)
entry:
br label %loop
loop:
%i = phi uint [ 4, %entry ], [ %i.next, %loop ]
%i.next = add uint %i, 8
%RV = div uint %i, 2
%c = setne uint %i, 68
br bool %c, label %loop, label %loopexit
loopexit:
ret uint %RV
}
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