[llvm-dev] LLVM 6.0's LoopUnroll PASS is not able to work?
Leslie Zhai via llvm-dev
llvm-dev at lists.llvm.org
Tue Oct 31 20:45:13 PDT 2017
Hi Jatin,
Wrongly use -loop-simplify produce this issue
https://github.com/epiqc/ScaffCC/issues/11
在 2017年10月27日 00:54, Jatin Bhateja 写道:
> Hi Leslie,
>
> There is a disable unroll meta data (!llvm.loop !2) associated with
> unCatN loop basic block , probaly in the source pragma clang loop
> unroll (disable) was used before the loop.
>
> I tried removing that and used -unroll-count=4 both the catN and
> uncatN were unrolled.
>
> Options : -mem2reg -loops -loop-simplify -loop-rotate -lcssa
> -loop-unroll -unroll-count=4 -sccp -simplifycfg -o /tmp/1
> -debug-only=loop-unroll.
>
> Loop Unroll: F[catN] Loop %for.body
> Loop Size = 17
> UNROLLING loop %for.body by 4!
> Loop Unroll: F[unCatN] Loop %for.body
> Loop Size = 9
> UNROLLING loop %for.body by 4 with run-time trip count!
>
> Thanks,
> Jatin
>
> On Wed, Oct 25, 2017 at 10:17 AM, Leslie Zhai via llvm-dev
> <llvm-dev at lists.llvm.org <mailto:llvm-dev at lists.llvm.org>> wrote:
>
> Hi Michael,
>
> Dropped *optnone* still failed to unroll loops for this testcase:
>
> $ cat cat_state.n044.ll
> ; ModuleID = 'cat_state.n045a.ll'
> source_filename = "cat_state.n04_merged.scaffold"
> target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
> target triple = "x86_64-unknown-linux-gnu"
>
> ; Function Attrs: noinline nounwind uwtable
> define void @catN(i16* %bit, i32 %n) local_unnamed_addr #0 {
> entry:
> %0 = load i16, i16* %bit, align 2
> tail call void @llvm.H.i16(i16 %0)
> %cmp1 = icmp sgt i32 %n, 1
> br i1 %cmp1, label %for.body.lr.ph <http://for.body.lr.ph>,
> label %for.end
>
> for.body.lr.ph <http://for.body.lr.ph>: ; preds = %entry
> %1 = add i32 %n, -1
> %2 = add i32 %n, -2
> %xtraiter = and i32 %1, 1
> %3 = icmp ult i32 %2, 1
> br i1 %3, label %for.cond.for.end_crit_edge.unr-lcssa, label
> %for.body.lr.ph.new
>
> for.body.lr.ph.new: ; preds = %for.body.lr.ph
> <http://for.body.lr.ph>
> %unroll_iter = sub i32 %1, %xtraiter
> br label %for.body
>
> for.body: ; preds = %for.body, %for.body.lr.ph.new
> %inc3 = phi i32 [ 1, %for.body.lr.ph.new ], [ %inc.1, %for.body ]
> %niter = phi i32 [ %unroll_iter, %for.body.lr.ph.new ], [
> %niter.nsub.1, %for.body ]
> %idxprom = sext i32 %inc3 to i64
> %arrayidx1 = getelementptr inbounds i16, i16* %bit, i64 %idxprom
> %4 = load i16, i16* %arrayidx1, align 2
> %sub = add nsw i32 %inc3, -1
> %idxprom2 = sext i32 %sub to i64
> %arrayidx3 = getelementptr inbounds i16, i16* %bit, i64 %idxprom2
> %5 = load i16, i16* %arrayidx3, align 2
> tail call void @llvm.CNOT.i16.i16(i16 %4, i16 %5)
> %inc = add nsw i32 %inc3, 1
> %niter.nsub = sub i32 %niter, 1
> %idxprom.1 = sext i32 %inc to i64
> %arrayidx1.1 = getelementptr inbounds i16, i16* %bit, i64 %idxprom.1
> %6 = load i16, i16* %arrayidx1.1, align 2
> %idxprom2.1 = sext i32 %inc3 to i64
> %arrayidx3.1 = getelementptr inbounds i16, i16* %bit, i64
> %idxprom2.1
> %7 = load i16, i16* %arrayidx3.1, align 2
> tail call void @llvm.CNOT.i16.i16(i16 %6, i16 %7)
> %inc.1 = add nsw i32 %inc, 1
> %niter.nsub.1 = sub i32 %niter.nsub, 1
> %niter.ncmp.1 = icmp ne i32 %niter.nsub.1, 0
> br i1 %niter.ncmp.1, label %for.body, label
> %for.cond.for.end_crit_edge.unr-lcssa
>
> for.cond.for.end_crit_edge.unr-lcssa: ; preds =
> %for.body, %for.body.lr.ph <http://for.body.lr.ph>
> %inc3.unr = phi i32 [ 1, %for.body.lr.ph <http://for.body.lr.ph>
> ], [ %inc.1, %for.body ]
> %lcmp.mod = icmp ne i32 %xtraiter, 0
> br i1 %lcmp.mod, label %for.body.epil, label %for.end
>
> for.body.epil: ; preds =
> %for.cond.for.end_crit_edge.unr-lcssa
> %inc3.epil = phi i32 [ %inc3.unr,
> %for.cond.for.end_crit_edge.unr-lcssa ]
> %idxprom.epil = sext i32 %inc3.epil to i64
> %arrayidx1.epil = getelementptr inbounds i16, i16* %bit, i64
> %idxprom.epil
> %8 = load i16, i16* %arrayidx1.epil, align 2
> %sub.epil = add nsw i32 %inc3.epil, -1
> %idxprom2.epil = sext i32 %sub.epil to i64
> %arrayidx3.epil = getelementptr inbounds i16, i16* %bit, i64
> %idxprom2.epil
> %9 = load i16, i16* %arrayidx3.epil, align 2
> tail call void @llvm.CNOT.i16.i16(i16 %8, i16 %9)
> %inc.epil = add nsw i32 %inc3.epil, 1
> %cmp.epil = icmp slt i32 %inc.epil, %n
> br label %for.end
>
> for.end: ; preds = %for.body.epil,
> %for.cond.for.end_crit_edge.unr-lcssa, %entry
> ret void
> }
>
> ; Function Attrs: nounwind
> declare void @llvm.H.i16(i16) #1
>
> ; Function Attrs: nounwind
> declare void @llvm.CNOT.i16.i16(i16, i16) #1
>
> ; Function Attrs: noinline nounwind uwtable
> define void @unCatN(i16* %bit, i32 %n) local_unnamed_addr #0 {
> entry:
> %storemerge1 = add nsw i32 %n, -1
> %cmp2 = icmp sgt i32 %n, 1
> br i1 %cmp2, label %for.body.peel, label %for.end
>
> for.body.peel: ; preds = %entry
> %idxprom.peel = sext i32 %storemerge1 to i64
> %arrayidx.peel = getelementptr inbounds i16, i16* %bit, i64
> %idxprom.peel
> %0 = load i16, i16* %arrayidx.peel, align 2
> %sub1.peel = add nsw i32 %n, -2
> %idxprom2.peel = sext i32 %sub1.peel to i64
> %arrayidx3.peel = getelementptr inbounds i16, i16* %bit, i64
> %idxprom2.peel
> %1 = load i16, i16* %arrayidx3.peel, align 2
> tail call void @llvm.CNOT.i16.i16(i16 %0, i16 %1)
> %storemerge.peel = add nsw i32 %storemerge1, -1
> %cmp.peel = icmp sgt i32 %storemerge1, 1
> br i1 %cmp.peel, label %for.body.lr.ph.peel.newph, label %for.end
>
> for.body.lr.ph.peel.newph: ; preds =
> %for.body.peel
> br label %for.body
>
> for.body: ; preds = %for.body,
> %for.body.lr.ph.peel.newph
> %storemerge5 = phi i32 [ %storemerge.peel,
> %for.body.lr.ph.peel.newph ], [ %storemerge, %for.body ]
> %storemerge.in3 = phi i32 [ %storemerge1,
> %for.body.lr.ph.peel.newph ], [ %storemerge5, %for.body ]
> %idxprom = sext i32 %storemerge5 to i64
> %arrayidx = getelementptr inbounds i16, i16* %bit, i64 %idxprom
> %2 = load i16, i16* %arrayidx, align 2
> %sub1 = add nsw i32 %storemerge.in3, -2
> %idxprom2 = sext i32 %sub1 to i64
> %arrayidx3 = getelementptr inbounds i16, i16* %bit, i64 %idxprom2
> %3 = load i16, i16* %arrayidx3, align 2
> tail call void @llvm.CNOT.i16.i16(i16 %2, i16 %3)
> %storemerge = add nsw i32 %storemerge5, -1
> %cmp = icmp sgt i32 %storemerge5, 1
> br i1 %cmp, label %for.body, label %for.end, !llvm.loop !2
>
> for.end: ; preds = %for.body, %for.body.peel,
> %entry
> %.lcssa = phi i16* [ %bit, %entry ], [ %bit, %for.body.peel ], [
> %bit, %for.body ]
> %4 = load i16, i16* %.lcssa, align 2
> tail call void @llvm.H.i16(i16 %4)
> ret void
> }
>
> ; Function Attrs: noinline nounwind uwtable
> define i32 @main() local_unnamed_addr #0 {
> entry:
> %bits = alloca [4 x i16], align 2
> %arraydecay = getelementptr inbounds [4 x i16], [4 x i16]*
> %bits, i64 0, i64 0
> call void @catN_IP4_IPx_IPx_IPx_DPx_DPx_DPx_DPx(i16*
> %arraydecay, i32 undef)
> ret i32 0
> }
>
> define void @catN_IP4_IPx_IPx_IPx_DPx_DPx_DPx_DPx(i16* %bit, i32 %n) {
> entry.:
> %0 = load i16, i16* %bit, align 2
> tail call void @llvm.H.i16(i16 %0)
> %arrayidx1. = getelementptr inbounds i16, i16* %bit, i64 1
> <https://maps.google.com/?q=i64+1&entry=gmail&source=g>
> %1 = load i16, i16* %arrayidx1., align 2
> %2 = load i16, i16* %bit, align 2
> tail call void @llvm.CNOT.i16.i16(i16 %1, i16 %2)
> %arrayidx1.1. = getelementptr inbounds i16, i16* %bit, i64 2
> <https://maps.google.com/?q=i64+2&entry=gmail&source=g>
> %3 = load i16, i16* %arrayidx1.1., align 2
> %arrayidx3.1. = getelementptr inbounds i16, i16* %bit, i64 1
> <https://maps.google.com/?q=i64+1&entry=gmail&source=g>
> %4 = load i16, i16* %arrayidx3.1., align 2
> tail call void @llvm.CNOT.i16.i16(i16 %3, i16 %4)
> %arrayidx1.epil. = getelementptr inbounds i16, i16* %bit, i64 3
> <https://maps.google.com/?q=i64+3&entry=gmail&source=g>
> %5 = load i16, i16* %arrayidx1.epil., align 2
> %arrayidx3.epil. = getelementptr inbounds i16, i16* %bit, i64 2
> <https://maps.google.com/?q=i64+2&entry=gmail&source=g>
> %6 = load i16, i16* %arrayidx3.epil., align 2
> tail call void @llvm.CNOT.i16.i16(i16 %5, i16 %6)
> ret void
> }
>
> attributes #0 = { noinline nounwind uwtable
> "correctly-rounded-divide-sqrt-fp-math"="false"
> "disable-tail-calls"="false" "less-precise-fpmad"="false"
> "no-frame-pointer-elim"="true" "no-frame-pointer-elim-non-leaf"
> "no-infs-fp-math"="false" "no-jump-tables"="false"
> "no-nans-fp-math"="false" "no-signed-zeros-fp-math"="false"
> "no-trapping-math"="false" "stack-protector-buffer-size"="8"
> "target-cpu"="x86-64"
> "target-features"="+fxsr,+mmx,+sse,+sse2,+x87"
> "unsafe-fp-math"="false" "use-soft-float"="false" }
> attributes #1 = { nounwind }
>
> !llvm.module.flags = !{!0}
> !llvm.ident = !{!1}
>
> !0 = !{i32 1, !"wchar_size", i32 4}
> !1 = !{!"clang version 6.0.0 (git at github.com:llvm-mirror/clang.git
> 0aed123216ad4a38a9c2b16f1783895fd5cb1a04)
> (git at github.com:llvm-mirror/llvm.git
> d209b37aec1e392dabbf9b5324ea4a60c36fbc55)"}
> !2 = distinct !{!2, !3}
> !3 = !{!"llvm.loop.unroll.disable"}
>
> $(OPT) -S cat_state.n044.ll -mem2reg -loops -loop-simplify
> -loop-rotate -lcssa -loop-unroll -unroll-threshold=100000000 -sccp
> -simplifycfg -o cat_state.n045.ll
>
> $ cat cat_state.n045.ll
> ; ModuleID = 'cat_state.n044.ll'
> source_filename = "cat_state.n04_merged.scaffold"
> target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
> target triple = "x86_64-unknown-linux-gnu"
>
> ; Function Attrs: noinline nounwind uwtable
> define void @catN(i16* %bit, i32 %n) local_unnamed_addr #0 {
> entry:
> %0 = load i16, i16* %bit, align 2
> tail call void @llvm.H.i16(i16 %0)
> %cmp1 = icmp sgt i32 %n, 1
> br i1 %cmp1, label %for.body.lr.ph <http://for.body.lr.ph>,
> label %for.end
>
> for.body.lr.ph <http://for.body.lr.ph>: ; preds = %entry
> %1 = add i32 %n, -1
> %2 = add i32 %n, -2
> %xtraiter = and i32 %1, 1
> %3 = icmp ult i32 %2, 1
> br i1 %3, label %for.cond.for.end_crit_edge.unr-lcssa, label
> %for.body.lr.ph.new
>
> for.body.lr.ph.new: ; preds = %for.body.lr.ph
> <http://for.body.lr.ph>
> %unroll_iter = sub i32 %1, %xtraiter
> br label %for.body
>
> for.body: ; preds = %for.body, %for.body.lr.ph.new
> %inc3 = phi i32 [ 1, %for.body.lr.ph.new ], [ %inc.1, %for.body ]
> %niter = phi i32 [ %unroll_iter, %for.body.lr.ph.new ], [
> %niter.nsub.1, %for.body ]
> %idxprom = sext i32 %inc3 to i64
> %arrayidx1 = getelementptr inbounds i16, i16* %bit, i64 %idxprom
> %4 = load i16, i16* %arrayidx1, align 2
> %sub = add nsw i32 %inc3, -1
> %idxprom2 = sext i32 %sub to i64
> %arrayidx3 = getelementptr inbounds i16, i16* %bit, i64 %idxprom2
> %5 = load i16, i16* %arrayidx3, align 2
> tail call void @llvm.CNOT.i16.i16(i16 %4, i16 %5)
> %inc = add nsw i32 %inc3, 1
> %niter.nsub = sub i32 %niter, 1
> %idxprom.1 = sext i32 %inc to i64
> %arrayidx1.1 = getelementptr inbounds i16, i16* %bit, i64 %idxprom.1
> %6 = load i16, i16* %arrayidx1.1, align 2
> %idxprom2.1 = sext i32 %inc3 to i64
> %arrayidx3.1 = getelementptr inbounds i16, i16* %bit, i64
> %idxprom2.1
> %7 = load i16, i16* %arrayidx3.1, align 2
> tail call void @llvm.CNOT.i16.i16(i16 %6, i16 %7)
> %inc.1 = add nsw i32 %inc, 1
> %niter.nsub.1 = sub i32 %niter.nsub, 1
> %niter.ncmp.1 = icmp ne i32 %niter.nsub.1, 0
> br i1 %niter.ncmp.1, label %for.body, label
> %for.cond.for.end_crit_edge.unr-lcssa
>
> for.cond.for.end_crit_edge.unr-lcssa: ; preds =
> %for.body, %for.body.lr.ph <http://for.body.lr.ph>
> %inc3.unr = phi i32 [ 1, %for.body.lr.ph <http://for.body.lr.ph>
> ], [ %inc.1, %for.body ]
> %lcmp.mod = icmp ne i32 %xtraiter, 0
> br i1 %lcmp.mod, label %for.body.epil, label %for.end
>
> for.body.epil: ; preds =
> %for.cond.for.end_crit_edge.unr-lcssa
> %inc3.epil = phi i32 [ %inc3.unr,
> %for.cond.for.end_crit_edge.unr-lcssa ]
> %idxprom.epil = sext i32 %inc3.epil to i64
> %arrayidx1.epil = getelementptr inbounds i16, i16* %bit, i64
> %idxprom.epil
> %8 = load i16, i16* %arrayidx1.epil, align 2
> %sub.epil = add nsw i32 %inc3.epil, -1
> %idxprom2.epil = sext i32 %sub.epil to i64
> %arrayidx3.epil = getelementptr inbounds i16, i16* %bit, i64
> %idxprom2.epil
> %9 = load i16, i16* %arrayidx3.epil, align 2
> tail call void @llvm.CNOT.i16.i16(i16 %8, i16 %9)
> %inc.epil = add nsw i32 %inc3.epil, 1
> %cmp.epil = icmp slt i32 %inc.epil, %n
> br label %for.end
>
> for.end: ; preds = %for.body.epil,
> %for.cond.for.end_crit_edge.unr-lcssa, %entry
> ret void
> }
>
> ; Function Attrs: nounwind
> declare void @llvm.H.i16(i16) #1
>
> ; Function Attrs: nounwind
> declare void @llvm.CNOT.i16.i16(i16, i16) #1
>
> ; Function Attrs: noinline nounwind uwtable
> define void @unCatN(i16* %bit, i32 %n) local_unnamed_addr #0 {
> entry:
> %storemerge1 = add nsw i32 %n, -1
> %cmp2 = icmp sgt i32 %n, 1
> br i1 %cmp2, label %for.body.peel, label %for.end
>
> for.body.peel: ; preds = %entry
> %idxprom.peel = sext i32 %storemerge1 to i64
> %arrayidx.peel = getelementptr inbounds i16, i16* %bit, i64
> %idxprom.peel
> %0 = load i16, i16* %arrayidx.peel, align 2
> %sub1.peel = add nsw i32 %n, -2
> %idxprom2.peel = sext i32 %sub1.peel to i64
> %arrayidx3.peel = getelementptr inbounds i16, i16* %bit, i64
> %idxprom2.peel
> %1 = load i16, i16* %arrayidx3.peel, align 2
> tail call void @llvm.CNOT.i16.i16(i16 %0, i16 %1)
> %storemerge.peel = add nsw i32 %storemerge1, -1
> %cmp.peel = icmp sgt i32 %storemerge1, 1
> br i1 %cmp.peel, label %for.body.lr.ph.peel.newph, label %for.end
>
> for.body.lr.ph.peel.newph: ; preds =
> %for.body.peel
> br label %for.body
>
> for.body: ; preds = %for.body,
> %for.body.lr.ph.peel.newph
> %storemerge5 = phi i32 [ %storemerge.peel,
> %for.body.lr.ph.peel.newph ], [ %storemerge, %for.body ]
> %storemerge.in3 = phi i32 [ %storemerge1,
> %for.body.lr.ph.peel.newph ], [ %storemerge5, %for.body ]
> %idxprom = sext i32 %storemerge5 to i64
> %arrayidx = getelementptr inbounds i16, i16* %bit, i64 %idxprom
> %2 = load i16, i16* %arrayidx, align 2
> %sub1 = add nsw i32 %storemerge.in3, -2
> %idxprom2 = sext i32 %sub1 to i64
> %arrayidx3 = getelementptr inbounds i16, i16* %bit, i64 %idxprom2
> %3 = load i16, i16* %arrayidx3, align 2
> tail call void @llvm.CNOT.i16.i16(i16 %2, i16 %3)
> %storemerge = add nsw i32 %storemerge5, -1
> %cmp = icmp sgt i32 %storemerge5, 1
> br i1 %cmp, label %for.body, label %for.end, !llvm.loop !2
>
> for.end: ; preds = %for.body, %for.body.peel,
> %entry
> %.lcssa = phi i16* [ %bit, %entry ], [ %bit, %for.body.peel ], [
> %bit, %for.body ]
> %4 = load i16, i16* %.lcssa, align 2
> tail call void @llvm.H.i16(i16 %4)
> ret void
> }
>
> ; Function Attrs: noinline nounwind uwtable
> define i32 @main() local_unnamed_addr #0 {
> entry:
> %bits = alloca [4 x i16], align 2
> %arraydecay = getelementptr inbounds [4 x i16], [4 x i16]*
> %bits, i64 0, i64 0
> call void @catN_IP4_IPx_IPx_IPx_DPx_DPx_DPx_DPx(i16*
> %arraydecay, i32 undef)
> ret i32 0
> }
>
> define void @catN_IP4_IPx_IPx_IPx_DPx_DPx_DPx_DPx(i16* %bit, i32 %n) {
> entry.:
> %0 = load i16, i16* %bit, align 2
> tail call void @llvm.H.i16(i16 %0)
> %arrayidx1. = getelementptr inbounds i16, i16* %bit, i64 1
> <https://maps.google.com/?q=i64+1&entry=gmail&source=g>
> %1 = load i16, i16* %arrayidx1., align 2
> %2 = load i16, i16* %bit, align 2
> tail call void @llvm.CNOT.i16.i16(i16 %1, i16 %2)
> %arrayidx1.1. = getelementptr inbounds i16, i16* %bit, i64 2
> <https://maps.google.com/?q=i64+2&entry=gmail&source=g>
> %3 = load i16, i16* %arrayidx1.1., align 2
> %arrayidx3.1. = getelementptr inbounds i16, i16* %bit, i64 1
> <https://maps.google.com/?q=i64+1&entry=gmail&source=g>
> %4 = load i16, i16* %arrayidx3.1., align 2
> tail call void @llvm.CNOT.i16.i16(i16 %3, i16 %4)
> %arrayidx1.epil. = getelementptr inbounds i16, i16* %bit, i64 3
> <https://maps.google.com/?q=i64+3&entry=gmail&source=g>
> %5 = load i16, i16* %arrayidx1.epil., align 2
> %arrayidx3.epil. = getelementptr inbounds i16, i16* %bit, i64 2
> <https://maps.google.com/?q=i64+2&entry=gmail&source=g>
> %6 = load i16, i16* %arrayidx3.epil., align 2
> tail call void @llvm.CNOT.i16.i16(i16 %5, i16 %6)
> ret void
> }
>
> attributes #0 = { noinline nounwind uwtable
> "correctly-rounded-divide-sqrt-fp-math"="false"
> "disable-tail-calls"="false" "less-precise-fpmad"="false"
> "no-frame-pointer-elim"="true" "no-frame-pointer-elim-non-leaf"
> "no-infs-fp-math"="false" "no-jump-tables"="false"
> "no-nans-fp-math"="false" "no-signed-zeros-fp-math"="false"
> "no-trapping-math"="false" "stack-protector-buffer-size"="8"
> "target-cpu"="x86-64"
> "target-features"="+fxsr,+mmx,+sse,+sse2,+x87"
> "unsafe-fp-math"="false" "use-soft-float"="false" }
> attributes #1 = { nounwind }
>
> !llvm.module.flags = !{!0}
> !llvm.ident = !{!1}
>
> !0 = !{i32 1, !"wchar_size", i32 4}
> !1 = !{!"clang version 6.0.0 (git at github.com:llvm-mirror/clang.git
> 0aed123216ad4a38a9c2b16f1783895fd5cb1a04)
> (git at github.com:llvm-mirror/llvm.git
> d209b37aec1e392dabbf9b5324ea4a60c36fbc55)"}
> !2 = distinct !{!2, !3}
> !3 = !{!"llvm.loop.unroll.disable"}
>
>
> There are still for *loops* in catN and unCatN Functions,
> workaround might be using GlobalDCE PASS towards cat_state.n045.ll
> to remove !Live DeadFunctions.
>
> Cat_State testcase:
> https://github.com/ScaffCC/ScaffCC/blob/master/Algorithms/Cat_State/cat_state.n04.scaffold
> <https://github.com/ScaffCC/ScaffCC/blob/master/Algorithms/Cat_State/cat_state.n04.scaffold>
>
> Scaffold builtin gates:
> https://github.com/ScaffCC/scaff-clang/blob/master/include/clang/Basic/Builtins.def#L108
> <https://github.com/ScaffCC/scaff-clang/blob/master/include/clang/Basic/Builtins.def#L108>
>
> Ali JavadiAbhari, Shruti Patil, Daniel Kudrow, Jeff Heckey, Alexey
> Lvov, Frederic Chong and Margaret Martonosi, ScaffCC: A Framework
> for Compilation and Analysis of Quantum Computing Programs, ACM
> International Conference on Computing Frontiers (CF 2014),
> Cagliari, Italy, May 2014
>
>
> 在 2017年10月24日 12:52, Michael Kruse 写道:
>
> 2017-10-24 6:19 GMT+02:00 Leslie Zhai via llvm-dev
> <llvm-dev at lists.llvm.org <mailto:llvm-dev at lists.llvm.org>
> <mailto:llvm-dev at lists.llvm.org
> <mailto:llvm-dev at lists.llvm.org>>>:
> > attributes #0 = { noinline nounwind *optnone *uwtable
>
> The optnone attribute (added by clang in -O0) says LLV? to not
> apply any transformation. Avoid with -Xclang -disable-O0-optnone
>
> Michael
>
>
> --
> Regards,
> Leslie Zhai - https://reviews.llvm.org/p/xiangzhai/
> <https://reviews.llvm.org/p/xiangzhai/>
>
>
>
> _______________________________________________
> LLVM Developers mailing list
> llvm-dev at lists.llvm.org <mailto:llvm-dev at lists.llvm.org>
> http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev
> <http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev>
>
>
--
Regards,
Leslie Zhai - https://reviews.llvm.org/p/xiangzhai/
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