llvm-6502/test/Analysis/ScalarEvolution/2008-02-12-SMAXTripCount.ll

; RUN: opt < %s -scalar-evolution -analyze -disable-output | grep {Loop %loop: backedge-taken count is (100 + (-100 smax %n))}
; PR2002

define void @foo(i8 %n) {
entry:
	br label %loop
loop:
	%i = phi i8 [ -100, %entry ], [ %i.inc, %next ]
	%cond = icmp slt i8 %i, %n
	br i1 %cond, label %next, label %return
next:
        %i.inc = add i8 %i, 1
	br label %loop
return:
	ret void
}
Use WriteAsOperand instead of getName() to print loop header names, so that unnamed blocks are handled. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93059 91177308-0d34-0410-b5e6-96231b3b80d8 2010-01-09 18:17:45 +00:00			`; RUN: opt < %s -scalar-evolution -analyze -disable-output \| grep {Loop %loop: backedge-taken count is (100 + (-100 smax %n))}`
Fix PR2002. Suppose n is the initial value for the induction variable (with step 1) and m is its final value. Then, the correct trip count is SMAX(m,n)-n. Previously, we used SMAX(0,m-n), but m-n may overflow and can't in general be interpreted as signed. Patch by Nick Lewycky. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47007 91177308-0d34-0410-b5e6-96231b3b80d8 2008-02-12 15:09:36 +00:00			`; PR2002`

			`define void @foo(i8 %n) {`
			`entry:`
			`br label %loop`
			`loop:`
			`%i = phi i8 [ -100, %entry ], [ %i.inc, %next ]`
			`%cond = icmp slt i8 %i, %n`
			`br i1 %cond, label %next, label %return`
			`next:`
			`%i.inc = add i8 %i, 1`
			`br label %loop`
			`return:`
			`ret void`
			`}`