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e027d74733
Summary: This change teaches isImpliedCond to infer things like "X sgt 0" => "X - 1 sgt -1". The `ConstantRange` class has the logic to do the heavy lifting, this change simply gets ScalarEvolution to exploit that when reasonable. Depends on D8345 Reviewers: atrick Subscribers: llvm-commits Differential Revision: http://reviews.llvm.org/D8346 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@232576 91177308-0d34-0410-b5e6-96231b3b80d8
31 lines
755 B
LLVM
31 lines
755 B
LLVM
; RUN: opt -indvars -S < %s | FileCheck %s
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define void @infer_via_ranges(i32 *%arr, i32 %n) {
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; CHECK-LABEL: @infer_via_ranges
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entry:
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%first.itr.check = icmp sgt i32 %n, 0
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%start = sub i32 %n, 1
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br i1 %first.itr.check, label %loop, label %exit
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loop:
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; CHECK-LABEL: loop:
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%idx = phi i32 [ %start, %entry ] , [ %idx.dec, %in.bounds ]
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%idx.dec = sub i32 %idx, 1
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%abc = icmp sge i32 %idx, 0
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; CHECK: br i1 true, label %in.bounds, label %out.of.bounds
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br i1 %abc, label %in.bounds, label %out.of.bounds
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in.bounds:
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; CHECK-LABEL: in.bounds:
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%addr = getelementptr i32, i32* %arr, i32 %idx
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store i32 0, i32* %addr
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%next = icmp sgt i32 %idx.dec, -1
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br i1 %next, label %loop, label %exit
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out.of.bounds:
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ret void
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exit:
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ret void
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}
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