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https://github.com/c64scene-ar/llvm-6502.git
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23b0065f29
If the loop trip count may underflow or wrap, the compiler should not generate a hardware loop since the trip count will be incorrect. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237365 91177308-0d34-0410-b5e6-96231b3b80d8
46 lines
1.4 KiB
LLVM
46 lines
1.4 KiB
LLVM
;RUN: llc -march=hexagon < %s | FileCheck %s
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; Test that a hardware loop is not generaetd due to a potential
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; underflow.
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; CHECK-NOT: loop0
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define i32 @main() #0 {
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entry:
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br label %while.cond.outer
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while.cond.outer.loopexit:
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%.lcssa = phi i32 [ %0, %for.body.preheader ]
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br label %while.cond.outer
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while.cond.outer:
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%i.0.ph = phi i32 [ 0, %entry ], [ 3, %while.cond.outer.loopexit ]
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%j.0.ph = phi i32 [ 0, %entry ], [ %.lcssa, %while.cond.outer.loopexit ]
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%k.0.ph = phi i32 [ 0, %entry ], [ 1, %while.cond.outer.loopexit ]
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br label %while.cond
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while.cond:
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%i.0 = phi i32 [ %i.0.ph, %while.cond.outer ], [ %inc, %for.body.preheader ]
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%j.0 = phi i32 [ %j.0.ph, %while.cond.outer ], [ %0, %for.body.preheader ]
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%inc = add nsw i32 %i.0, 1
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%cmp = icmp slt i32 %i.0, 4
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br i1 %cmp, label %for.body.preheader, label %while.end
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for.body.preheader:
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%0 = add i32 %j.0, 3
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%cmp5 = icmp eq i32 %inc, 3
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br i1 %cmp5, label %while.cond.outer.loopexit, label %while.cond
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while.end:
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%k.0.ph.lcssa = phi i32 [ %k.0.ph, %while.cond ]
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%inc.lcssa = phi i32 [ %inc, %while.cond ]
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%j.0.lcssa = phi i32 [ %j.0, %while.cond ]
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%cmp6 = icmp ne i32 %inc.lcssa, 5
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%cmp7 = icmp ne i32 %j.0.lcssa, 12
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%or.cond = or i1 %cmp6, %cmp7
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%cmp9 = icmp ne i32 %k.0.ph.lcssa, 1
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%or.cond12 = or i1 %or.cond, %cmp9
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%locflg.0 = zext i1 %or.cond12 to i32
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ret i32 %locflg.0
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}
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