llvm-6502/test/Transforms/LoopStrengthReduce/count-to-zero.ll
Dan Gohman 572645cf84 Reapply the new LoopStrengthReduction code, with compile time and
bug fixes, and with improved heuristics for analyzing foreign-loop
addrecs.

This change also flattens IVUsers, eliminating the stride-oriented
groupings, which makes it easier to work with.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95975 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-12 10:34:29 +00:00

43 lines
1.6 KiB
LLVM

; RUN: opt < %s -loop-reduce -S | FileCheck %s
; rdar://7382068
define void @t(i32 %c) nounwind optsize {
entry:
br label %bb6
bb1: ; preds = %bb6
%tmp = icmp eq i32 %c_addr.1, 20 ; <i1> [#uses=1]
br i1 %tmp, label %bb2, label %bb3
bb2: ; preds = %bb1
%tmp1 = tail call i32 @f20(i32 %c_addr.1) nounwind ; <i32> [#uses=1]
br label %bb7
bb3: ; preds = %bb1
%tmp2 = icmp slt i32 %c_addr.1, 10 ; <i1> [#uses=1]
%tmp3 = add nsw i32 %c_addr.1, 1 ; <i32> [#uses=1]
%tmp4 = add i32 %c_addr.1, -1 ; <i32> [#uses=1]
%c_addr.1.be = select i1 %tmp2, i32 %tmp3, i32 %tmp4 ; <i32> [#uses=1]
%indvar.next = add i32 %indvar, 1 ; <i32> [#uses=1]
; CHECK: add i32 %lsr.iv, -1
br label %bb6
bb6: ; preds = %bb3, %entry
%indvar = phi i32 [ %indvar.next, %bb3 ], [ 0, %entry ] ; <i32> [#uses=2]
%c_addr.1 = phi i32 [ %c_addr.1.be, %bb3 ], [ %c, %entry ] ; <i32> [#uses=7]
%tmp5 = icmp eq i32 %indvar, 9999 ; <i1> [#uses=1]
; CHECK: icmp eq i32 %lsr.iv, 0
%tmp6 = icmp eq i32 %c_addr.1, 100 ; <i1> [#uses=1]
%or.cond = or i1 %tmp5, %tmp6 ; <i1> [#uses=1]
br i1 %or.cond, label %bb7, label %bb1
bb7: ; preds = %bb6, %bb2
%c_addr.0 = phi i32 [ %tmp1, %bb2 ], [ %c_addr.1, %bb6 ] ; <i32> [#uses=1]
tail call void @bar(i32 %c_addr.0) nounwind
ret void
}
declare i32 @f20(i32)
declare void @bar(i32)