llvm/test/Analysis/DependenceAnalysis/NonAffineExpr.ll
Matthew Simpson cc8cfb9875 [SCEV] Consistently Handle Expressions That Cannot Be Divided
This patch addresses the issue of SCEV division asserting on some
input expressions (e.g., non-affine expressions) and quietly giving
up on others.  When giving up, we set the quotient to be equal to
zero and the remainder to be equal to the numerator. With this
patch, we always quietly give up when we cannot perform the
division.

This patch also adds a test case for DependenceAnalysis that
previously caused an assertion.

Differential Revision: http://reviews.llvm.org/D11725

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@247314 91177308-0d34-0410-b5e6-96231b3b80d8
2015-09-10 18:12:47 +00:00

37 lines
1.0 KiB
LLVM

; RUN: opt < %s -analyze -basicaa -da-delinearize -da
;
; CHECK: da analyze - consistent input [S S]!
; CHECK: da analyze - confused!
; CHECK: da analyze - input [* *]!
;
target datalayout = "e-m:e-p:32:32-i64:64-v128:64:128-a:0:32-n8:16:32-S64"
target triple = "thumbv7--linux-gnueabi"
define void @f(i32** %a, i32 %n) align 2 {
for.preheader:
%t.0 = ashr exact i32 %n, 3
br label %for.body.1
for.body.1:
%i.1 = phi i32 [ %t.5, %for.inc ], [ 0, %for.preheader ]
%i.2 = phi i32 [ %i.5, %for.inc ], [ %t.0, %for.preheader ]
br i1 undef, label %for.inc, label %for.body.2
for.body.2:
%i.3 = phi i32 [ %t.1, %for.body.2 ], [ %i.1, %for.body.1 ]
%t.1 = add i32 %i.3, 1
%t.2 = load i32*, i32** %a, align 4
%t.3 = getelementptr inbounds i32, i32* %t.2, i32 %i.3
%t.4 = load i32, i32* %t.3, align 4
br i1 undef, label %for.inc, label %for.body.2
for.inc:
%i.4 = phi i32 [ %i.2, %for.body.1 ], [ %i.2, %for.body.2 ]
%t.5 = add i32 %i.1, %i.4
%i.5 = add i32 %i.2, -1
br i1 undef, label %for.exit, label %for.body.1
for.exit:
ret void
}