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llvm-project/polly/test/ScopInfo/simple_loop_unsigned_3.ll

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Allow unsigned comparisons With this patch we will optimistically assume that the result of an unsigned comparison is the same as the result of the same comparison interpreted as signed. llvm-svn: 267559
2016-04-26 22:33:12 +08:00
; RUN: opt %loadPolly -polly-scops -analyze < %s | FileCheck %s
; CHECK: Assumed Context:
; CHECK-NEXT: [N] -> { : }
;
; CHECK: Domain :=
[ScopInfo] Add support for wrap-around of integers in unsigned comparisons. This is one possible solution to implement wrap-arounds for integers in unsigned icmp operations. For example, store i32 -1, i32* %A_addr %0 = load i32, i32* %A_addr %1 = icmp ult i32 %0, 0 %1 should hold false, because under the assumption of unsigned integers, -1 should wrap around to 2^32-1. However, previously. it was assumed that the MSB (Most Significant Bit - aka the Sign bit) was never set for integers in unsigned operations. This patch modifies the buildConditionSets function in ScopInfo.cpp to give better information about the integers in these unsigned comparisons. Contributed-by: Annanay Agarwal <cs14btech11001@iith.ac.in> Differential Revision: https://reviews.llvm.org/D35464 llvm-svn: 308608
2017-07-20 20:37:02 +08:00
; CHECK-NEXT: [N] -> { Stmt_bb[0] };
Allow unsigned comparisons With this patch we will optimistically assume that the result of an unsigned comparison is the same as the result of the same comparison interpreted as signed. llvm-svn: 267559
2016-04-26 22:33:12 +08:00
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"
define void @f(i64* nocapture %a, i64 %N) nounwind {
entry:
br label %bb
bb: ; preds = %bb, %entry
%i = phi i64 [ 1000, %entry ], [ %i.dec, %bb ]
%scevgep = getelementptr inbounds i64, i64* %a, i64 %i
store i64 %i, i64* %scevgep
%i.dec = add nsw i64 %i, -1
%sub = sub nsw i64 %N, %i
%exitcond = icmp ult i64 %sub, 0
br i1 %exitcond, label %bb, label %return
return: ; preds = %bb, %entry
ret void
}