llvm-6502/test/Analysis/ScalarEvolution/2008-02-11-ReversedCondition.ll

; RUN: opt < %s -scalar-evolution -analyze -disable-output | grep {Loop header: backedge-taken count is (0 smax %n)}

define void @foo(i32 %n) {
entry:
	br label %header
header:
	%i = phi i32 [ 0, %entry ], [ %i.inc, %next ]
	%cond = icmp sgt i32 %n, %i
	br i1 %cond, label %next, label %return
next:
        %i.inc = add i32 %i, 1
	br label %header
return:
	ret void
}
Change tests from "opt %s" to "opt < %s" so that opt doesn't see the input filename so that opt doesn't print the input filename in the output so that grep lines in the tests don't unintentionally match strings in the input filename. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@81537 91177308-0d34-0410-b5e6-96231b3b80d8 2009-09-11 18:01:28 +00:00			`; RUN: opt < %s -scalar-evolution -analyze -disable-output \| grep {Loop header: backedge-taken count is (0 smax %n)}`
If the LHS of the comparison is a loop-invariant we also want to move it to the RHS. This simple change allows to compute loop iteration count for loops with condition similar to the one in the testcase (which seems to be quite common). git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@46959 91177308-0d34-0410-b5e6-96231b3b80d8 2008-02-11 18:37:34 +00:00
			`define void @foo(i32 %n) {`
			`entry:`
			`br label %header`
			`header:`
			`%i = phi i32 [ 0, %entry ], [ %i.inc, %next ]`
			`%cond = icmp sgt i32 %n, %i`
			`br i1 %cond, label %next, label %return`
			`next:`
			`%i.inc = add i32 %i, 1`
			`br label %header`
			`return:`
			`ret void`
			`}`