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; 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 -loop-deletion -simplifycfg | llvm-dis | not grep br
define i32 @linear_setne() {
entry:
br label %loop
loop: ; preds = %loop, %entry
%i = phi i32 [ 0, %entry ], [ %i.next, %loop ] ; <i32> [#uses=3]
%i.next = add i32 %i, 1 ; <i32> [#uses=1]
%c = icmp ne i32 %i, 100 ; <i1> [#uses=1]
br i1 %c, label %loop, label %loopexit
loopexit: ; preds = %loop
ret i32 %i
}
define i32 @linear_setne_2() {
entry:
br label %loop
loop: ; preds = %loop, %entry
%i = phi i32 [ 0, %entry ], [ %i.next, %loop ] ; <i32> [#uses=3]
%i.next = add i32 %i, 2 ; <i32> [#uses=1]
%c = icmp ne i32 %i, 100 ; <i1> [#uses=1]
br i1 %c, label %loop, label %loopexit
loopexit: ; preds = %loop
ret i32 %i
}
define i32 @linear_setne_overflow() {
entry:
br label %loop
loop: ; preds = %loop, %entry
%i = phi i32 [ 1024, %entry ], [ %i.next, %loop ] ; <i32> [#uses=3]
%i.next = add i32 %i, 1024 ; <i32> [#uses=1]
%c = icmp ne i32 %i, 0 ; <i1> [#uses=1]
br i1 %c, label %loop, label %loopexit
loopexit: ; preds = %loop
ret i32 %i
}
define i32 @linear_setlt() {
entry:
br label %loop
loop: ; preds = %loop, %entry
%i = phi i32 [ 0, %entry ], [ %i.next, %loop ] ; <i32> [#uses=3]
%i.next = add i32 %i, 1 ; <i32> [#uses=1]
%c = icmp slt i32 %i, 100 ; <i1> [#uses=1]
br i1 %c, label %loop, label %loopexit
loopexit: ; preds = %loop
ret i32 %i
}
define i32 @quadratic_setlt() {
entry:
br label %loop
loop: ; preds = %loop, %entry
%i = phi i32 [ 7, %entry ], [ %i.next, %loop ] ; <i32> [#uses=4]
%i.next = add i32 %i, 3 ; <i32> [#uses=1]
%i2 = mul i32 %i, %i ; <i32> [#uses=1]
%c = icmp slt i32 %i2, 1000 ; <i1> [#uses=1]
br i1 %c, label %loop, label %loopexit
loopexit: ; preds = %loop
ret i32 %i
}
define i32 @chained() {
entry:
br label %loop
loop: ; preds = %loop, %entry
%i = phi i32 [ 0, %entry ], [ %i.next, %loop ] ; <i32> [#uses=3]
%i.next = add i32 %i, 1 ; <i32> [#uses=1]
%c = icmp ne i32 %i, 100 ; <i1> [#uses=1]
br i1 %c, label %loop, label %loopexit
loopexit: ; preds = %loop
br label %loop2
loop2: ; preds = %loop2, %loopexit
%j = phi i32 [ %i, %loopexit ], [ %j.next, %loop2 ] ; <i32> [#uses=3]
%j.next = add i32 %j, 1 ; <i32> [#uses=1]
%c2 = icmp ne i32 %j, 200 ; <i1> [#uses=1]
br i1 %c2, label %loop2, label %loopexit2
loopexit2: ; preds = %loop2
ret i32 %j
}
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