From fe3516f9a5f238ecf6872b5315706c7c7942a496 Mon Sep 17 00:00:00 2001 From: Andrew Trick Date: Wed, 30 May 2012 03:35:20 +0000 Subject: SCEV: Handle a corner case reducing AddRecExpr * AddRecExpr If integer overflow causes one of the terms to reach zero, that can force the entire expression to zero. Fixes PR12929: cast() argument of incompatible type git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@157673 91177308-0d34-0410-b5e6-96231b3b80d8 --- .../ScalarEvolution/2012-05-29-MulAddRec.ll | 45 ++++++++++++++++++++++ 1 file changed, 45 insertions(+) create mode 100644 test/Analysis/ScalarEvolution/2012-05-29-MulAddRec.ll (limited to 'test/Analysis') diff --git a/test/Analysis/ScalarEvolution/2012-05-29-MulAddRec.ll b/test/Analysis/ScalarEvolution/2012-05-29-MulAddRec.ll new file mode 100644 index 0000000..eee4ec4 --- /dev/null +++ b/test/Analysis/ScalarEvolution/2012-05-29-MulAddRec.ll @@ -0,0 +1,45 @@ +; RUN: opt < %s -S -indvars -loop-unroll | FileCheck %s +; +; loop-unroll fully unrolls the inner loop, creating an interesting +; chain of multiplication. indvars forces SCEV to run again on the +; outer loop. While reducing the recurrence at %mul3, unsigned integer overflow +; causes one of the terms to reach zero. This forces all multiples in +; the recurrence to be zero, reducing the whole thing to a constant expression. +; +; PR12929: cast() argument of incompatible type + +; CHECK: @func +; CHECK: for.cond: +; CHECK: %inc1 = phi i8 [ 0, %entry ], [ %0, %for.body ] +; CHECK: br label %for.body + +; CHECK: for.body: +; CHECK: %inc.9 = add i8 %inc.8, 1 +; CHECK: %0 = add i8 %inc1, 10 +; CHEKC: br label %for.cond + +target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64-S128" +define void @func() noreturn nounwind uwtable ssp { +entry: + br label %for.cond + +for.cond.loopexit: ; preds = %for.body + %mul.lcssa = phi i8 [ %mul, %for.body ] + %0 = add i8 %inc1, 10 + %indvars.iv.next = add i8 %indvars.iv, 10 + br label %for.cond + +for.cond: ; preds = %for.cond.loopexit, %entry + %indvars.iv = phi i8 [ %indvars.iv.next, %for.cond.loopexit ], [ 10, %entry ] + %mul3 = phi i8 [ undef, %entry ], [ %mul.lcssa, %for.cond.loopexit ] + %inc1 = phi i8 [ 0, %entry ], [ %0, %for.cond.loopexit ] + br label %for.body + +for.body: ; preds = %for.body, %for.cond + %inc26 = phi i8 [ %inc1, %for.cond ], [ %inc, %for.body ] + %mul45 = phi i8 [ %mul3, %for.cond ], [ %mul, %for.body ] + %inc = add i8 %inc26, 1 + %mul = mul i8 %inc26, %mul45 + %exitcond = icmp ne i8 %inc, %indvars.iv + br i1 %exitcond, label %for.body, label %for.cond.loopexit +} -- cgit v1.1