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https://github.com/c64scene-ar/llvm-6502.git
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994b4c784f
Runtime unrolling is an expensive optimization which can bring benefit only if the loop is hot and iteration number is relatively large enough. For some loops, we know they are not worth to be runtime unrolled. The scalar loop from vectorization is one of the cases. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@231631 91177308-0d34-0410-b5e6-96231b3b80d8
152 lines
5.3 KiB
LLVM
152 lines
5.3 KiB
LLVM
; RUN: opt < %s -S -loop-unroll -unroll-runtime=true | FileCheck %s
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; Tests for unrolling loops with run-time trip counts
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; CHECK: %xtraiter = and i32 %n
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; CHECK: %lcmp.mod = icmp ne i32 %xtraiter, 0
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; CHECK: br i1 %lcmp.mod, label %for.body.prol, label %for.body.preheader.split
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; CHECK: for.body.prol:
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; CHECK: %indvars.iv.prol = phi i64 [ %indvars.iv.next.prol, %for.body.prol ], [ 0, %for.body.preheader ]
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; CHECK: %prol.iter.sub = sub i32 %prol.iter, 1
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; CHECK: %prol.iter.cmp = icmp ne i32 %prol.iter.sub, 0
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; CHECK: br i1 %prol.iter.cmp, label %for.body.prol, label %for.body.preheader.split, !llvm.loop !0
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define i32 @test(i32* nocapture %a, i32 %n) nounwind uwtable readonly {
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entry:
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%cmp1 = icmp eq i32 %n, 0
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br i1 %cmp1, label %for.end, label %for.body
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for.body: ; preds = %for.body, %entry
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%indvars.iv = phi i64 [ %indvars.iv.next, %for.body ], [ 0, %entry ]
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%sum.02 = phi i32 [ %add, %for.body ], [ 0, %entry ]
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%arrayidx = getelementptr inbounds i32, i32* %a, i64 %indvars.iv
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%0 = load i32, i32* %arrayidx, align 4
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%add = add nsw i32 %0, %sum.02
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%indvars.iv.next = add i64 %indvars.iv, 1
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%lftr.wideiv = trunc i64 %indvars.iv.next to i32
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%exitcond = icmp eq i32 %lftr.wideiv, %n
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br i1 %exitcond, label %for.end, label %for.body
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for.end: ; preds = %for.body, %entry
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%sum.0.lcssa = phi i32 [ 0, %entry ], [ %add, %for.body ]
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ret i32 %sum.0.lcssa
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}
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; Still try to completely unroll loops with compile-time trip counts
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; even if the -unroll-runtime is specified
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; CHECK: for.body:
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; CHECK-NOT: for.body.prol:
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define i32 @test1(i32* nocapture %a) nounwind uwtable readonly {
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entry:
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br label %for.body
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for.body: ; preds = %for.body, %entry
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%indvars.iv = phi i64 [ 0, %entry ], [ %indvars.iv.next, %for.body ]
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%sum.01 = phi i32 [ 0, %entry ], [ %add, %for.body ]
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%arrayidx = getelementptr inbounds i32, i32* %a, i64 %indvars.iv
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%0 = load i32, i32* %arrayidx, align 4
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%add = add nsw i32 %0, %sum.01
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%indvars.iv.next = add i64 %indvars.iv, 1
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%lftr.wideiv = trunc i64 %indvars.iv.next to i32
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%exitcond = icmp eq i32 %lftr.wideiv, 5
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br i1 %exitcond, label %for.end, label %for.body
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for.end: ; preds = %for.body
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ret i32 %add
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}
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; This is test 2007-05-09-UnknownTripCount.ll which can be unrolled now
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; if the -unroll-runtime option is turned on
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; CHECK: bb72.2:
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define void @foo(i32 %trips) {
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entry:
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br label %cond_true.outer
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cond_true.outer:
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%indvar1.ph = phi i32 [ 0, %entry ], [ %indvar.next2, %bb72 ]
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br label %bb72
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bb72:
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%indvar.next2 = add i32 %indvar1.ph, 1
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%exitcond3 = icmp eq i32 %indvar.next2, %trips
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br i1 %exitcond3, label %cond_true138, label %cond_true.outer
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cond_true138:
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ret void
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}
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; Test run-time unrolling for a loop that counts down by -2.
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; CHECK: for.body.prol:
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; CHECK: br i1 %prol.iter.cmp, label %for.body.prol, label %for.body.preheader.split
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define zeroext i16 @down(i16* nocapture %p, i32 %len) nounwind uwtable readonly {
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entry:
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%cmp2 = icmp eq i32 %len, 0
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br i1 %cmp2, label %for.end, label %for.body
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for.body: ; preds = %for.body, %entry
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%p.addr.05 = phi i16* [ %incdec.ptr, %for.body ], [ %p, %entry ]
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%len.addr.04 = phi i32 [ %sub, %for.body ], [ %len, %entry ]
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%res.03 = phi i32 [ %add, %for.body ], [ 0, %entry ]
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%incdec.ptr = getelementptr inbounds i16, i16* %p.addr.05, i64 1
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%0 = load i16, i16* %p.addr.05, align 2
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%conv = zext i16 %0 to i32
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%add = add i32 %conv, %res.03
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%sub = add nsw i32 %len.addr.04, -2
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%cmp = icmp eq i32 %sub, 0
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br i1 %cmp, label %for.cond.for.end_crit_edge, label %for.body
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for.cond.for.end_crit_edge: ; preds = %for.body
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%phitmp = trunc i32 %add to i16
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br label %for.end
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for.end: ; preds = %for.cond.for.end_crit_edge, %entry
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%res.0.lcssa = phi i16 [ %phitmp, %for.cond.for.end_crit_edge ], [ 0, %entry ]
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ret i16 %res.0.lcssa
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}
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; Test run-time unrolling disable metadata.
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; CHECK: for.body:
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; CHECK-NOT: for.body.prol:
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define zeroext i16 @test2(i16* nocapture %p, i32 %len) nounwind uwtable readonly {
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entry:
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%cmp2 = icmp eq i32 %len, 0
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br i1 %cmp2, label %for.end, label %for.body
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for.body: ; preds = %for.body, %entry
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%p.addr.05 = phi i16* [ %incdec.ptr, %for.body ], [ %p, %entry ]
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%len.addr.04 = phi i32 [ %sub, %for.body ], [ %len, %entry ]
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%res.03 = phi i32 [ %add, %for.body ], [ 0, %entry ]
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%incdec.ptr = getelementptr inbounds i16, i16* %p.addr.05, i64 1
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%0 = load i16, i16* %p.addr.05, align 2
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%conv = zext i16 %0 to i32
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%add = add i32 %conv, %res.03
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%sub = add nsw i32 %len.addr.04, -2
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%cmp = icmp eq i32 %sub, 0
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br i1 %cmp, label %for.cond.for.end_crit_edge, label %for.body, !llvm.loop !0
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for.cond.for.end_crit_edge: ; preds = %for.body
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%phitmp = trunc i32 %add to i16
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br label %for.end
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for.end: ; preds = %for.cond.for.end_crit_edge, %entry
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%res.0.lcssa = phi i16 [ %phitmp, %for.cond.for.end_crit_edge ], [ 0, %entry ]
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ret i16 %res.0.lcssa
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}
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!0 = distinct !{!0, !1}
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!1 = !{!"llvm.loop.unroll.runtime.disable"}
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; CHECK: !0 = distinct !{!0, !1}
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; CHECK: !1 = !{!"llvm.loop.unroll.disable"}
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