Xiangyang Guo via llvm-dev
2015-Aug-22 15:47 UTC
[llvm-dev] loop unrolling introduces conditional branch
Thanks for your point that out. I just add DataLayout in my code such as
"mod->setDataLayout("e-m:e-i64:64-f80:128-n8:16:32:64-S128");",
still no
luck.
I'm really confused about this. Do I need to add more passes before
-loop-unroll?
On Sat, Aug 22, 2015 at 11:36 AM, Mehdi Amini <mehdi.amini at apple.com>
wrote:
>
> On Aug 22, 2015, at 7:27 AM, Xiangyang Guo <xguo6 at ncsu.edu> wrote:
>
> Hi, Mehdi,
>
> For example, I have this very simple source code:
> void foo( int n, int array_x[])
> {
> for (int i=0; i < n; i++)
> array_x[i] = i;
> }
>
> After I use "clang -emit-llvm -o bc_from_clang.bc -c try.cc", I
get
> bc_from_clang.bc. With my code (using LLVM IRbuilder API), I get
> bc_from_api.bc. Attachment please find thse two files. I also past the IR
> here.
> ******************************** Clang Generate IR Start
> ***********************************************************
> ; ModuleID = 'bc_from_clang.bc'
> target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
> target triple = "x86_64-unknown-linux-gnu"
>
> ; Function Attrs: nounwind uwtable
> define void @_Z3fooiPi(i32 %n, i32* %array_x) #0 {
> %1 = alloca i32, align 4
> %2 = alloca i32*, align 8
> %i = alloca i32, align 4
> store i32 %n, i32* %1, align 4
> store i32* %array_x, i32** %2, align 8
> store i32 0, i32* %i, align 4
> br label %3
>
> ; <label>:3 ; preds = %13, %0
> %4 = load i32, i32* %i, align 4
> %5 = load i32, i32* %1, align 4
> %6 = icmp slt i32 %4, %5
> br i1 %6, label %7, label %16
>
> ; <label>:7 ; preds = %3
> %8 = load i32, i32* %i, align 4
> %9 = load i32, i32* %i, align 4
> %10 = sext i32 %9 to i64
> %11 = load i32*, i32** %2, align 8
> %12 = getelementptr inbounds i32, i32* %11, i64 %10
> store i32 %8, i32* %12, align 4
> br label %13
>
> ; <label>:13 ; preds = %7
> %14 = load i32, i32* %i, align 4
> %15 = add nsw i32 %14, 1
> store i32 %15, i32* %i, align 4
> br label %3
>
> ; <label>:16 ; preds = %3
> ret void
> }
>
> attributes #0 = { nounwind uwtable
"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-nans-fp-math"="false"
"stack-protector-buffer-size"="8"
> "target-cpu"="x86-64"
"target-features"="+sse,+sse2"
> "unsafe-fp-math"="false"
"use-soft-float"="false" }
>
> !llvm.ident = !{!0}
>
> !0 = !{!"clang version 3.8.0 (trunk 245730) (llvm/trunk 245727)"}
>
> ******************************** Clang Generate IR End
> ***********************************************************
>
> ******************************** API Generate IR Start
> ***********************************************************
> ; ModuleID = 'bc_from_api.bc'
> target triple = "x86_64-unkown-linux-gnu"
>
> ; Function Attrs: nounwind
> define void @_Z3fooiPi(i32 %n, i32* %array_x) #0 {
> entry:
> %n.addr = alloca i32, align 4
> %array_x.addr = alloca i32*, align 8
> %i = alloca i32, align 4
> store i32 %n, i32* %n.addr, align 4
> store i32* %array_x, i32** %array_x.addr, align 8
> store i32 0, i32* %i, align 4
> br label %for.cond
>
> for.cond: ; preds = %for.inc,
> %entry
> %0 = load i32, i32* %i, align 4
> %1 = load i32, i32* %n.addr, align 4
> %cmp = icmp slt i32 %0, %1
> br i1 %cmp, label %for.body, label %for.end
>
> for.body: ; preds = %for.cond
> %2 = load i32, i32* %i, align 4
> %3 = load i32, i32* %i, align 4
> %idxprom = sext i32 %3 to i64
> %4 = load i32*, i32** %array_x.addr, align 8
> %arrayidx = getelementptr inbounds i32, i32* %4, i64 %idxprom
> store i32 %2, i32* %arrayidx, align 4
> br label %for.inc
>
> for.inc: ; preds = %for.body
> %5 = load i32, i32* %i, align 4
> %inc = add i32 %5, 1
> store i32 %inc, i32* %i, align 4
> br label %for.cond
>
> for.end: ; preds = %for.cond
> ret void
> }
>
> attributes #0 = { nounwind }
>
> ******************************** API Generate IR End
> ***********************************************************
>
> Then I use "opt file.bc -mem2reg -loops -loop-simplify -loop-rotate
-lcssa
> -indvars -loop-unroll -unroll-count=4 -irce -simplifycfg -S" to run
both
> .bc files.
> The first .bc file give me this:
>
> ***************************** Clang Generate IR with LoopUnrolling
> Start**********************************************
> ; ModuleID = 'bc_from_clang.bc'
> target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
> target triple = "x86_64-unknown-linux-gnu"
>
> ; Function Attrs: nounwind uwtable
> define void @_Z3fooiPi(i32 %n, i32* %array_x) #0 {
> %1 = icmp slt i32 0, %n
> br i1 %1, label %.lr.ph
>
<https://urldefense.proofpoint.com/v2/url?u=http-3A__lr.ph&d=BQMFaQ&c=eEvniauFctOgLOKGJOplqw&r=v-ruWq0KCv2O3thJZiK6naxuXK8mQHZUmGq5FBtAmZ4&m=9pD2qNHBiPJscAs-ZzWT7q61NeZNcwsY8Io52JnaI3E&s=OaVJWcn8TI03qp9lgqeWMIVMySoyBIPowkHDEyR7lvQ&e=>,
> label %._crit_edge
>
> .lr.ph
>
<https://urldefense.proofpoint.com/v2/url?u=http-3A__lr.ph&d=BQMFaQ&c=eEvniauFctOgLOKGJOplqw&r=v-ruWq0KCv2O3thJZiK6naxuXK8mQHZUmGq5FBtAmZ4&m=9pD2qNHBiPJscAs-ZzWT7q61NeZNcwsY8Io52JnaI3E&s=OaVJWcn8TI03qp9lgqeWMIVMySoyBIPowkHDEyR7lvQ&e=>:
> ; preds = %0
> %2 = add i32 %n, -1
> %xtraiter = and i32 %n, 3
> %lcmp.mod = icmp ne i32 %xtraiter, 0
> br i1 %lcmp.mod, label %3, label %.lr.ph.split
>
> ; <label>:3 ; preds = %3,
%.lr.ph
>
<https://urldefense.proofpoint.com/v2/url?u=http-3A__lr.ph&d=BQMFaQ&c=eEvniauFctOgLOKGJOplqw&r=v-ruWq0KCv2O3thJZiK6naxuXK8mQHZUmGq5FBtAmZ4&m=9pD2qNHBiPJscAs-ZzWT7q61NeZNcwsY8Io52JnaI3E&s=OaVJWcn8TI03qp9lgqeWMIVMySoyBIPowkHDEyR7lvQ&e=>
> %indvars.iv.prol = phi i64 [ 0, %.lr.ph
>
<https://urldefense.proofpoint.com/v2/url?u=http-3A__lr.ph&d=BQMFaQ&c=eEvniauFctOgLOKGJOplqw&r=v-ruWq0KCv2O3thJZiK6naxuXK8mQHZUmGq5FBtAmZ4&m=9pD2qNHBiPJscAs-ZzWT7q61NeZNcwsY8Io52JnaI3E&s=OaVJWcn8TI03qp9lgqeWMIVMySoyBIPowkHDEyR7lvQ&e=>
> ], [ %indvars.iv.next.prol, %3 ]
> %prol.iter = phi i32 [ %xtraiter, %.lr.ph
>
<https://urldefense.proofpoint.com/v2/url?u=http-3A__lr.ph&d=BQMFaQ&c=eEvniauFctOgLOKGJOplqw&r=v-ruWq0KCv2O3thJZiK6naxuXK8mQHZUmGq5FBtAmZ4&m=9pD2qNHBiPJscAs-ZzWT7q61NeZNcwsY8Io52JnaI3E&s=OaVJWcn8TI03qp9lgqeWMIVMySoyBIPowkHDEyR7lvQ&e=>
> ], [ %prol.iter.sub, %3 ]
> %4 = getelementptr inbounds i32, i32* %array_x, i64 %indvars.iv.prol
> %5 = trunc i64 %indvars.iv.prol to i32
> store i32 %5, i32* %4, align 4
> %indvars.iv.next.prol = add nuw nsw i64 %indvars.iv.prol, 1
> %lftr.wideiv.prol = trunc i64 %indvars.iv.next.prol to i32
> %exitcond.prol = icmp ne i32 %lftr.wideiv.prol, %n
> %prol.iter.sub = sub i32 %prol.iter, 1
> %prol.iter.cmp = icmp ne i32 %prol.iter.sub, 0
> br i1 %prol.iter.cmp, label %3, label %.lr.ph.split, !llvm.loop !1
>
> .lr.ph.split: ; preds = %3, %.lr.ph
>
<https://urldefense.proofpoint.com/v2/url?u=http-3A__lr.ph&d=BQMFaQ&c=eEvniauFctOgLOKGJOplqw&r=v-ruWq0KCv2O3thJZiK6naxuXK8mQHZUmGq5FBtAmZ4&m=9pD2qNHBiPJscAs-ZzWT7q61NeZNcwsY8Io52JnaI3E&s=OaVJWcn8TI03qp9lgqeWMIVMySoyBIPowkHDEyR7lvQ&e=>
> %indvars.iv.unr = phi i64 [ 0, %.lr.ph
>
<https://urldefense.proofpoint.com/v2/url?u=http-3A__lr.ph&d=BQMFaQ&c=eEvniauFctOgLOKGJOplqw&r=v-ruWq0KCv2O3thJZiK6naxuXK8mQHZUmGq5FBtAmZ4&m=9pD2qNHBiPJscAs-ZzWT7q61NeZNcwsY8Io52JnaI3E&s=OaVJWcn8TI03qp9lgqeWMIVMySoyBIPowkHDEyR7lvQ&e=>
> ], [ %indvars.iv.next.prol, %3 ]
> %6 = icmp ult i32 %2, 3
> br i1 %6, label %._crit_edge, label %.lr.ph.split.split
>
> .lr.ph.split.split: ; preds = %.lr.ph.split,
> %.lr.ph.split.split
> %indvars.iv = phi i64 [ %indvars.iv.next.3, %.lr.ph.split.split ], [
> %indvars.iv.unr, %.lr.ph.split ]
> %7 = getelementptr inbounds i32, i32* %array_x, i64 %indvars.iv
> %8 = trunc i64 %indvars.iv to i32
> store i32 %8, i32* %7, align 4
> %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
> %lftr.wideiv = trunc i64 %indvars.iv.next to i32
> %9 = getelementptr inbounds i32, i32* %array_x, i64 %indvars.iv.next
> %10 = trunc i64 %indvars.iv.next to i32
> store i32 %10, i32* %9, align 4
> %indvars.iv.next.1 = add nuw nsw i64 %indvars.iv.next, 1
> %lftr.wideiv.1 = trunc i64 %indvars.iv.next.1 to i32
> %11 = getelementptr inbounds i32, i32* %array_x, i64 %indvars.iv.next.1
> %12 = trunc i64 %indvars.iv.next.1 to i32
> store i32 %12, i32* %11, align 4
> %indvars.iv.next.2 = add nuw nsw i64 %indvars.iv.next.1, 1
> %lftr.wideiv.2 = trunc i64 %indvars.iv.next.2 to i32
> %13 = getelementptr inbounds i32, i32* %array_x, i64 %indvars.iv.next.2
> %14 = trunc i64 %indvars.iv.next.2 to i32
> store i32 %14, i32* %13, align 4
> %indvars.iv.next.3 = add nuw nsw i64 %indvars.iv.next.2, 1
> %lftr.wideiv.3 = trunc i64 %indvars.iv.next.3 to i32
> %exitcond.3 = icmp ne i32 %lftr.wideiv.3, %n
> br i1 %exitcond.3, label %.lr.ph.split.split, label %._crit_edge
>
> ._crit_edge: ; preds = %.lr.ph.split,
> %.lr.ph.split.split, %0
> ret void
> }
>
> attributes #0 = { nounwind uwtable
"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-nans-fp-math"="false"
"stack-protector-buffer-size"="8"
> "target-cpu"="x86-64"
"target-features"="+sse,+sse2"
> "unsafe-fp-math"="false"
"use-soft-float"="false" }
>
> !llvm.ident = !{!0}
>
> !0 = !{!"clang version 3.8.0 (trunk 245730) (llvm/trunk 245727)"}
> !1 = distinct !{!1, !2}
> !2 = !{!"llvm.loop.unroll.disable"}
>
> ******************************Clang Generate IR with LoopUnrolling
> End***********************************************
>
> The second .bc file gives me this:
> ******************************API Generate IR with LoopUnrolling
> Start*************************************************
> ; ModuleID = 'bc_from_api.bc'
> target triple = "x86_64-unkown-linux-gnu"
>
> ; Function Attrs: nounwind
> define void @_Z3fooiPi(i32 %n, i32* %array_x) #0 {
> entry:
> %cmp.1 = icmp slt i32 0, %n
> br i1 %cmp.1, label %for.body, label %for.end
>
> for.body: ; preds = %entry,
> %for.body.3
> %i.02 = phi i32 [ %inc.3, %for.body.3 ], [ 0, %entry ]
> %idxprom = sext i32 %i.02 to i64
> %arrayidx = getelementptr inbounds i32, i32* %array_x, i64 %idxprom
> store i32 %i.02, i32* %arrayidx, align 4
> %inc = add nuw nsw i32 %i.02, 1
> %cmp = icmp slt i32 %inc, %n
> br i1 %cmp, label %for.body.1, label %for.end
>
> for.end: ; preds = %for.body,
> %for.body.1, %for.body.2, %for.body.3, %entry
> ret void
>
> for.body.1: ; preds = %for.body
> %idxprom.1 = sext i32 %inc to i64
> %arrayidx.1 = getelementptr inbounds i32, i32* %array_x, i64 %idxprom.1
> store i32 %inc, i32* %arrayidx.1, align 4
> %inc.1 = add nuw nsw i32 %inc, 1
> %cmp.1.3 = icmp slt i32 %inc.1, %n
> br i1 %cmp.1.3, label %for.body.2, label %for.end
>
> for.body.2: ; preds = %for.body.1
> %idxprom.2 = sext i32 %inc.1 to i64
> %arrayidx.2 = getelementptr inbounds i32, i32* %array_x, i64 %idxprom.2
> store i32 %inc.1, i32* %arrayidx.2, align 4
> %inc.2 = add nuw nsw i32 %inc.1, 1
> %cmp.2 = icmp slt i32 %inc.2, %n
> br i1 %cmp.2, label %for.body.3, label %for.end
>
> for.body.3: ; preds = %for.body.2
> %idxprom.3 = sext i32 %inc.2 to i64
> %arrayidx.3 = getelementptr inbounds i32, i32* %array_x, i64 %idxprom.3
> store i32 %inc.2, i32* %arrayidx.3, align 4
> %inc.3 = add nuw nsw i32 %inc.2, 1
> %cmp.3 = icmp slt i32 %inc.3, %n
> br i1 %cmp.3, label %for.body, label %for.end
> }
>
> attributes #0 = { nounwind }
> ******************************API Generate IR with LoopUnrolling
> End**************************************************
>
> Sorry I post two many code here. Can you give me any suggestion?
>
>
> Yes, use an online service like pastebin :)
>
> You don’t have defined the DataLayout in the API cases, it should help to
> do so.
>
> —
> Mehdi
>
>
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Mehdi Amini via llvm-dev
2015-Aug-22 17:17 UTC
[llvm-dev] loop unrolling introduces conditional branch
There is something fishy, can you try adding copy/pasting the datalayout in the .ll file? When I did it I ended up with the same result for the two IR with opt. — Mehdi> On Aug 22, 2015, at 8:47 AM, Xiangyang Guo <xguo6 at ncsu.edu> wrote: > > Thanks for your point that out. I just add DataLayout in my code such as "mod->setDataLayout("e-m:e-i64:64-f80:128-n8:16:32:64-S128");", still no luck. > > I'm really confused about this. Do I need to add more passes before -loop-unroll? > > On Sat, Aug 22, 2015 at 11:36 AM, Mehdi Amini <mehdi.amini at apple.com <mailto:mehdi.amini at apple.com>> wrote: > >> On Aug 22, 2015, at 7:27 AM, Xiangyang Guo <xguo6 at ncsu.edu <mailto:xguo6 at ncsu.edu>> wrote: >> >> Hi, Mehdi, >> >> For example, I have this very simple source code: >> void foo( int n, int array_x[]) >> { >> for (int i=0; i < n; i++) >> array_x[i] = i; >> } >> >> After I use "clang -emit-llvm -o bc_from_clang.bc -c try.cc <https://urldefense.proofpoint.com/v2/url?u=http-3A__try.cc&d=BQMFaQ&c=eEvniauFctOgLOKGJOplqw&r=v-ruWq0KCv2O3thJZiK6naxuXK8mQHZUmGq5FBtAmZ4&m=Md4uZe64Q--bOhDzJswg35Dg5r4vcRon11DYXKI7lWU&s=KFMdI-L8rtHmALGsOCSPwRv8wIbnj6gXzo7sub9gRPw&e=>", I get bc_from_clang.bc. With my code (using LLVM IRbuilder API), I get bc_from_api.bc. Attachment please find thse two files. I also past the IR here. >> ******************************** Clang Generate IR Start *********************************************************** >> ; ModuleID = 'bc_from_clang.bc' >> target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128" >> target triple = "x86_64-unknown-linux-gnu" >> >> ; Function Attrs: nounwind uwtable >> define void @_Z3fooiPi(i32 %n, i32* %array_x) #0 { >> %1 = alloca i32, align 4 >> %2 = alloca i32*, align 8 >> %i = alloca i32, align 4 >> store i32 %n, i32* %1, align 4 >> store i32* %array_x, i32** %2, align 8 >> store i32 0, i32* %i, align 4 >> br label %3 >> >> ; <label>:3 ; preds = %13, %0 >> %4 = load i32, i32* %i, align 4 >> %5 = load i32, i32* %1, align 4 >> %6 = icmp slt i32 %4, %5 >> br i1 %6, label %7, label %16 >> >> ; <label>:7 ; preds = %3 >> %8 = load i32, i32* %i, align 4 >> %9 = load i32, i32* %i, align 4 >> %10 = sext i32 %9 to i64 >> %11 = load i32*, i32** %2, align 8 >> %12 = getelementptr inbounds i32, i32* %11, i64 %10 >> store i32 %8, i32* %12, align 4 >> br label %13 >> >> ; <label>:13 ; preds = %7 >> %14 = load i32, i32* %i, align 4 >> %15 = add nsw i32 %14, 1 >> store i32 %15, i32* %i, align 4 >> br label %3 >> >> ; <label>:16 ; preds = %3 >> ret void >> } >> >> attributes #0 = { nounwind uwtable "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-nans-fp-math"="false" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+sse,+sse2" "unsafe-fp-math"="false" "use-soft-float"="false" } >> >> !llvm.ident = !{!0} >> >> !0 = !{!"clang version 3.8.0 (trunk 245730) (llvm/trunk 245727)"} >> >> ******************************** Clang Generate IR End *********************************************************** >> >> ******************************** API Generate IR Start *********************************************************** >> ; ModuleID = 'bc_from_api.bc' >> target triple = "x86_64-unkown-linux-gnu" >> >> ; Function Attrs: nounwind >> define void @_Z3fooiPi(i32 %n, i32* %array_x) #0 { >> entry: >> %n.addr = alloca i32, align 4 >> %array_x.addr = alloca i32*, align 8 >> %i = alloca i32, align 4 >> store i32 %n, i32* %n.addr, align 4 >> store i32* %array_x, i32** %array_x.addr, align 8 >> store i32 0, i32* %i, align 4 >> br label %for.cond >> >> for.cond: ; preds = %for.inc, %entry >> %0 = load i32, i32* %i, align 4 >> %1 = load i32, i32* %n.addr, align 4 >> %cmp = icmp slt i32 %0, %1 >> br i1 %cmp, label %for.body, label %for.end >> >> for.body: ; preds = %for.cond >> %2 = load i32, i32* %i, align 4 >> %3 = load i32, i32* %i, align 4 >> %idxprom = sext i32 %3 to i64 >> %4 = load i32*, i32** %array_x.addr, align 8 >> %arrayidx = getelementptr inbounds i32, i32* %4, i64 %idxprom >> store i32 %2, i32* %arrayidx, align 4 >> br label %for.inc >> >> for.inc: ; preds = %for.body >> %5 = load i32, i32* %i, align 4 >> %inc = add i32 %5, 1 >> store i32 %inc, i32* %i, align 4 >> br label %for.cond >> >> for.end: ; preds = %for.cond >> ret void >> } >> >> attributes #0 = { nounwind } >> >> ******************************** API Generate IR End *********************************************************** >> >> Then I use "opt file.bc -mem2reg -loops -loop-simplify -loop-rotate -lcssa -indvars -loop-unroll -unroll-count=4 -irce -simplifycfg -S" to run both .bc files. >> The first .bc file give me this: >> >> ***************************** Clang Generate IR with LoopUnrolling Start********************************************** >> ; ModuleID = 'bc_from_clang.bc' >> target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128" >> target triple = "x86_64-unknown-linux-gnu" >> >> ; Function Attrs: nounwind uwtable >> define void @_Z3fooiPi(i32 %n, i32* %array_x) #0 { >> %1 = icmp slt i32 0, %n >> br i1 %1, label %.lr.ph <https://urldefense.proofpoint.com/v2/url?u=http-3A__lr.ph&d=BQMFaQ&c=eEvniauFctOgLOKGJOplqw&r=v-ruWq0KCv2O3thJZiK6naxuXK8mQHZUmGq5FBtAmZ4&m=9pD2qNHBiPJscAs-ZzWT7q61NeZNcwsY8Io52JnaI3E&s=OaVJWcn8TI03qp9lgqeWMIVMySoyBIPowkHDEyR7lvQ&e=>, label %._crit_edge >> >> .lr.ph <https://urldefense.proofpoint.com/v2/url?u=http-3A__lr.ph&d=BQMFaQ&c=eEvniauFctOgLOKGJOplqw&r=v-ruWq0KCv2O3thJZiK6naxuXK8mQHZUmGq5FBtAmZ4&m=9pD2qNHBiPJscAs-ZzWT7q61NeZNcwsY8Io52JnaI3E&s=OaVJWcn8TI03qp9lgqeWMIVMySoyBIPowkHDEyR7lvQ&e=>: ; preds = %0 >> %2 = add i32 %n, -1 >> %xtraiter = and i32 %n, 3 >> %lcmp.mod = icmp ne i32 %xtraiter, 0 >> br i1 %lcmp.mod, label %3, label %.lr.ph.split >> >> ; <label>:3 ; preds = %3, %.lr.ph <https://urldefense.proofpoint.com/v2/url?u=http-3A__lr.ph&d=BQMFaQ&c=eEvniauFctOgLOKGJOplqw&r=v-ruWq0KCv2O3thJZiK6naxuXK8mQHZUmGq5FBtAmZ4&m=9pD2qNHBiPJscAs-ZzWT7q61NeZNcwsY8Io52JnaI3E&s=OaVJWcn8TI03qp9lgqeWMIVMySoyBIPowkHDEyR7lvQ&e=> >> %indvars.iv.prol = phi i64 [ 0, %.lr.ph <https://urldefense.proofpoint.com/v2/url?u=http-3A__lr.ph&d=BQMFaQ&c=eEvniauFctOgLOKGJOplqw&r=v-ruWq0KCv2O3thJZiK6naxuXK8mQHZUmGq5FBtAmZ4&m=9pD2qNHBiPJscAs-ZzWT7q61NeZNcwsY8Io52JnaI3E&s=OaVJWcn8TI03qp9lgqeWMIVMySoyBIPowkHDEyR7lvQ&e=> ], [ %indvars.iv.next.prol, %3 ] >> %prol.iter = phi i32 [ %xtraiter, %.lr.ph <https://urldefense.proofpoint.com/v2/url?u=http-3A__lr.ph&d=BQMFaQ&c=eEvniauFctOgLOKGJOplqw&r=v-ruWq0KCv2O3thJZiK6naxuXK8mQHZUmGq5FBtAmZ4&m=9pD2qNHBiPJscAs-ZzWT7q61NeZNcwsY8Io52JnaI3E&s=OaVJWcn8TI03qp9lgqeWMIVMySoyBIPowkHDEyR7lvQ&e=> ], [ %prol.iter.sub, %3 ] >> %4 = getelementptr inbounds i32, i32* %array_x, i64 %indvars.iv.prol >> %5 = trunc i64 %indvars.iv.prol to i32 >> store i32 %5, i32* %4, align 4 >> %indvars.iv.next.prol = add nuw nsw i64 %indvars.iv.prol, 1 >> %lftr.wideiv.prol = trunc i64 %indvars.iv.next.prol to i32 >> %exitcond.prol = icmp ne i32 %lftr.wideiv.prol, %n >> %prol.iter.sub = sub i32 %prol.iter, 1 >> %prol.iter.cmp = icmp ne i32 %prol.iter.sub, 0 >> br i1 %prol.iter.cmp, label %3, label %.lr.ph.split, !llvm.loop !1 >> >> .lr.ph.split: ; preds = %3, %.lr.ph <https://urldefense.proofpoint.com/v2/url?u=http-3A__lr.ph&d=BQMFaQ&c=eEvniauFctOgLOKGJOplqw&r=v-ruWq0KCv2O3thJZiK6naxuXK8mQHZUmGq5FBtAmZ4&m=9pD2qNHBiPJscAs-ZzWT7q61NeZNcwsY8Io52JnaI3E&s=OaVJWcn8TI03qp9lgqeWMIVMySoyBIPowkHDEyR7lvQ&e=> >> %indvars.iv.unr = phi i64 [ 0, %.lr.ph <https://urldefense.proofpoint.com/v2/url?u=http-3A__lr.ph&d=BQMFaQ&c=eEvniauFctOgLOKGJOplqw&r=v-ruWq0KCv2O3thJZiK6naxuXK8mQHZUmGq5FBtAmZ4&m=9pD2qNHBiPJscAs-ZzWT7q61NeZNcwsY8Io52JnaI3E&s=OaVJWcn8TI03qp9lgqeWMIVMySoyBIPowkHDEyR7lvQ&e=> ], [ %indvars.iv.next.prol, %3 ] >> %6 = icmp ult i32 %2, 3 >> br i1 %6, label %._crit_edge, label %.lr.ph.split.split >> >> .lr.ph.split.split: ; preds = %.lr.ph.split, %.lr.ph.split.split >> %indvars.iv = phi i64 [ %indvars.iv.next.3, %.lr.ph.split.split ], [ %indvars.iv.unr, %.lr.ph.split ] >> %7 = getelementptr inbounds i32, i32* %array_x, i64 %indvars.iv >> %8 = trunc i64 %indvars.iv to i32 >> store i32 %8, i32* %7, align 4 >> %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1 >> %lftr.wideiv = trunc i64 %indvars.iv.next to i32 >> %9 = getelementptr inbounds i32, i32* %array_x, i64 %indvars.iv.next >> %10 = trunc i64 %indvars.iv.next to i32 >> store i32 %10, i32* %9, align 4 >> %indvars.iv.next.1 = add nuw nsw i64 %indvars.iv.next, 1 >> %lftr.wideiv.1 = trunc i64 %indvars.iv.next.1 to i32 >> %11 = getelementptr inbounds i32, i32* %array_x, i64 %indvars.iv.next.1 >> %12 = trunc i64 %indvars.iv.next.1 to i32 >> store i32 %12, i32* %11, align 4 >> %indvars.iv.next.2 = add nuw nsw i64 %indvars.iv.next.1, 1 >> %lftr.wideiv.2 = trunc i64 %indvars.iv.next.2 to i32 >> %13 = getelementptr inbounds i32, i32* %array_x, i64 %indvars.iv.next.2 >> %14 = trunc i64 %indvars.iv.next.2 to i32 >> store i32 %14, i32* %13, align 4 >> %indvars.iv.next.3 = add nuw nsw i64 %indvars.iv.next.2, 1 >> %lftr.wideiv.3 = trunc i64 %indvars.iv.next.3 to i32 >> %exitcond.3 = icmp ne i32 %lftr.wideiv.3, %n >> br i1 %exitcond.3, label %.lr.ph.split.split, label %._crit_edge >> >> ._crit_edge: ; preds = %.lr.ph.split, %.lr.ph.split.split, %0 >> ret void >> } >> >> attributes #0 = { nounwind uwtable "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-nans-fp-math"="false" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+sse,+sse2" "unsafe-fp-math"="false" "use-soft-float"="false" } >> >> !llvm.ident = !{!0} >> >> !0 = !{!"clang version 3.8.0 (trunk 245730) (llvm/trunk 245727)"} >> !1 = distinct !{!1, !2} >> !2 = !{!"llvm.loop.unroll.disable"} >> >> ******************************Clang Generate IR with LoopUnrolling End*********************************************** >> >> The second .bc file gives me this: >> ******************************API Generate IR with LoopUnrolling Start************************************************* >> ; ModuleID = 'bc_from_api.bc' >> target triple = "x86_64-unkown-linux-gnu" >> >> ; Function Attrs: nounwind >> define void @_Z3fooiPi(i32 %n, i32* %array_x) #0 { >> entry: >> %cmp.1 = icmp slt i32 0, %n >> br i1 %cmp.1, label %for.body, label %for.end >> >> for.body: ; preds = %entry, %for.body.3 >> %i.02 = phi i32 [ %inc.3, %for.body.3 ], [ 0, %entry ] >> %idxprom = sext i32 %i.02 to i64 >> %arrayidx = getelementptr inbounds i32, i32* %array_x, i64 %idxprom >> store i32 %i.02, i32* %arrayidx, align 4 >> %inc = add nuw nsw i32 %i.02, 1 >> %cmp = icmp slt i32 %inc, %n >> br i1 %cmp, label %for.body.1, label %for.end >> >> for.end: ; preds = %for.body, %for.body.1, %for.body.2, %for.body.3, %entry >> ret void >> >> for.body.1: ; preds = %for.body >> %idxprom.1 = sext i32 %inc to i64 >> %arrayidx.1 = getelementptr inbounds i32, i32* %array_x, i64 %idxprom.1 >> store i32 %inc, i32* %arrayidx.1, align 4 >> %inc.1 = add nuw nsw i32 %inc, 1 >> %cmp.1.3 = icmp slt i32 %inc.1, %n >> br i1 %cmp.1.3, label %for.body.2, label %for.end >> >> for.body.2: ; preds = %for.body.1 >> %idxprom.2 = sext i32 %inc.1 to i64 >> %arrayidx.2 = getelementptr inbounds i32, i32* %array_x, i64 %idxprom.2 >> store i32 %inc.1, i32* %arrayidx.2, align 4 >> %inc.2 = add nuw nsw i32 %inc.1, 1 >> %cmp.2 = icmp slt i32 %inc.2, %n >> br i1 %cmp.2, label %for.body.3, label %for.end >> >> for.body.3: ; preds = %for.body.2 >> %idxprom.3 = sext i32 %inc.2 to i64 >> %arrayidx.3 = getelementptr inbounds i32, i32* %array_x, i64 %idxprom.3 >> store i32 %inc.2, i32* %arrayidx.3, align 4 >> %inc.3 = add nuw nsw i32 %inc.2, 1 >> %cmp.3 = icmp slt i32 %inc.3, %n >> br i1 %cmp.3, label %for.body, label %for.end >> } >> >> attributes #0 = { nounwind } >> ******************************API Generate IR with LoopUnrolling End************************************************** >> >> Sorry I post two many code here. Can you give me any suggestion? > > Yes, use an online service like pastebin :) > > You don’t have defined the DataLayout in the API cases, it should help to do so. > > — > Mehdi > >-------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20150822/fd5ad1c5/attachment.html>
Michael Zolotukhin via llvm-dev
2015-Aug-22 18:13 UTC
[llvm-dev] loop unrolling introduces conditional branch
Hi Xiangyang, I also see that the function attributes differ - I think that’s the reason. When I added the attributes and target data-layout to the abi-file, both of them yielded me the same output (minus some blocks and variable names). Thanks, Michael> On Aug 22, 2015, at 10:17 AM, Mehdi Amini via llvm-dev <llvm-dev at lists.llvm.org> wrote: > > There is something fishy, can you try adding copy/pasting the datalayout in the .ll file? > When I did it I ended up with the same result for the two IR with opt. > > — > Mehdi > >> On Aug 22, 2015, at 8:47 AM, Xiangyang Guo <xguo6 at ncsu.edu <mailto:xguo6 at ncsu.edu>> wrote: >> >> Thanks for your point that out. I just add DataLayout in my code such as "mod->setDataLayout("e-m:e-i64:64-f80:128-n8:16:32:64-S128");", still no luck. >> >> I'm really confused about this. Do I need to add more passes before -loop-unroll? >> >> On Sat, Aug 22, 2015 at 11:36 AM, Mehdi Amini <mehdi.amini at apple.com <mailto:mehdi.amini at apple.com>> wrote: >> >>> On Aug 22, 2015, at 7:27 AM, Xiangyang Guo <xguo6 at ncsu.edu <mailto:xguo6 at ncsu.edu>> wrote: >>> >>> Hi, Mehdi, >>> >>> For example, I have this very simple source code: >>> void foo( int n, int array_x[]) >>> { >>> for (int i=0; i < n; i++) >>> array_x[i] = i; >>> } >>> >>> After I use "clang -emit-llvm -o bc_from_clang.bc -c try.cc <https://urldefense.proofpoint.com/v2/url?u=http-3A__try.cc&d=BQMFaQ&c=eEvniauFctOgLOKGJOplqw&r=v-ruWq0KCv2O3thJZiK6naxuXK8mQHZUmGq5FBtAmZ4&m=Md4uZe64Q--bOhDzJswg35Dg5r4vcRon11DYXKI7lWU&s=KFMdI-L8rtHmALGsOCSPwRv8wIbnj6gXzo7sub9gRPw&e=>", I get bc_from_clang.bc. With my code (using LLVM IRbuilder API), I get bc_from_api.bc. Attachment please find thse two files. I also past the IR here. >>> ******************************** Clang Generate IR Start *********************************************************** >>> ; ModuleID = 'bc_from_clang.bc' >>> target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128" >>> target triple = "x86_64-unknown-linux-gnu" >>> >>> ; Function Attrs: nounwind uwtable >>> define void @_Z3fooiPi(i32 %n, i32* %array_x) #0 { >>> %1 = alloca i32, align 4 >>> %2 = alloca i32*, align 8 >>> %i = alloca i32, align 4 >>> store i32 %n, i32* %1, align 4 >>> store i32* %array_x, i32** %2, align 8 >>> store i32 0, i32* %i, align 4 >>> br label %3 >>> >>> ; <label>:3 ; preds = %13, %0 >>> %4 = load i32, i32* %i, align 4 >>> %5 = load i32, i32* %1, align 4 >>> %6 = icmp slt i32 %4, %5 >>> br i1 %6, label %7, label %16 >>> >>> ; <label>:7 ; preds = %3 >>> %8 = load i32, i32* %i, align 4 >>> %9 = load i32, i32* %i, align 4 >>> %10 = sext i32 %9 to i64 >>> %11 = load i32*, i32** %2, align 8 >>> %12 = getelementptr inbounds i32, i32* %11, i64 %10 >>> store i32 %8, i32* %12, align 4 >>> br label %13 >>> >>> ; <label>:13 ; preds = %7 >>> %14 = load i32, i32* %i, align 4 >>> %15 = add nsw i32 %14, 1 >>> store i32 %15, i32* %i, align 4 >>> br label %3 >>> >>> ; <label>:16 ; preds = %3 >>> ret void >>> } >>> >>> attributes #0 = { nounwind uwtable "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-nans-fp-math"="false" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+sse,+sse2" "unsafe-fp-math"="false" "use-soft-float"="false" } >>> >>> !llvm.ident = !{!0} >>> >>> !0 = !{!"clang version 3.8.0 (trunk 245730) (llvm/trunk 245727)"} >>> >>> ******************************** Clang Generate IR End *********************************************************** >>> >>> ******************************** API Generate IR Start *********************************************************** >>> ; ModuleID = 'bc_from_api.bc' >>> target triple = "x86_64-unkown-linux-gnu" >>> >>> ; Function Attrs: nounwind >>> define void @_Z3fooiPi(i32 %n, i32* %array_x) #0 { >>> entry: >>> %n.addr = alloca i32, align 4 >>> %array_x.addr = alloca i32*, align 8 >>> %i = alloca i32, align 4 >>> store i32 %n, i32* %n.addr, align 4 >>> store i32* %array_x, i32** %array_x.addr, align 8 >>> store i32 0, i32* %i, align 4 >>> br label %for.cond >>> >>> for.cond: ; preds = %for.inc, %entry >>> %0 = load i32, i32* %i, align 4 >>> %1 = load i32, i32* %n.addr, align 4 >>> %cmp = icmp slt i32 %0, %1 >>> br i1 %cmp, label %for.body, label %for.end >>> >>> for.body: ; preds = %for.cond >>> %2 = load i32, i32* %i, align 4 >>> %3 = load i32, i32* %i, align 4 >>> %idxprom = sext i32 %3 to i64 >>> %4 = load i32*, i32** %array_x.addr, align 8 >>> %arrayidx = getelementptr inbounds i32, i32* %4, i64 %idxprom >>> store i32 %2, i32* %arrayidx, align 4 >>> br label %for.inc >>> >>> for.inc: ; preds = %for.body >>> %5 = load i32, i32* %i, align 4 >>> %inc = add i32 %5, 1 >>> store i32 %inc, i32* %i, align 4 >>> br label %for.cond >>> >>> for.end: ; preds = %for.cond >>> ret void >>> } >>> >>> attributes #0 = { nounwind } >>> >>> ******************************** API Generate IR End *********************************************************** >>> >>> Then I use "opt file.bc -mem2reg -loops -loop-simplify -loop-rotate -lcssa -indvars -loop-unroll -unroll-count=4 -irce -simplifycfg -S" to run both .bc files. >>> The first .bc file give me this: >>> >>> ***************************** Clang Generate IR with LoopUnrolling Start********************************************** >>> ; ModuleID = 'bc_from_clang.bc' >>> target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128" >>> target triple = "x86_64-unknown-linux-gnu" >>> >>> ; Function Attrs: nounwind uwtable >>> define void @_Z3fooiPi(i32 %n, i32* %array_x) #0 { >>> %1 = icmp slt i32 0, %n >>> br i1 %1, label %.lr.ph <https://urldefense.proofpoint.com/v2/url?u=http-3A__lr.ph&d=BQMFaQ&c=eEvniauFctOgLOKGJOplqw&r=v-ruWq0KCv2O3thJZiK6naxuXK8mQHZUmGq5FBtAmZ4&m=9pD2qNHBiPJscAs-ZzWT7q61NeZNcwsY8Io52JnaI3E&s=OaVJWcn8TI03qp9lgqeWMIVMySoyBIPowkHDEyR7lvQ&e=>, label %._crit_edge >>> >>> .lr.ph <https://urldefense.proofpoint.com/v2/url?u=http-3A__lr.ph&d=BQMFaQ&c=eEvniauFctOgLOKGJOplqw&r=v-ruWq0KCv2O3thJZiK6naxuXK8mQHZUmGq5FBtAmZ4&m=9pD2qNHBiPJscAs-ZzWT7q61NeZNcwsY8Io52JnaI3E&s=OaVJWcn8TI03qp9lgqeWMIVMySoyBIPowkHDEyR7lvQ&e=>: ; preds = %0 >>> %2 = add i32 %n, -1 >>> %xtraiter = and i32 %n, 3 >>> %lcmp.mod = icmp ne i32 %xtraiter, 0 >>> br i1 %lcmp.mod, label %3, label %.lr.ph.split >>> >>> ; <label>:3 ; preds = %3, %.lr.ph <https://urldefense.proofpoint.com/v2/url?u=http-3A__lr.ph&d=BQMFaQ&c=eEvniauFctOgLOKGJOplqw&r=v-ruWq0KCv2O3thJZiK6naxuXK8mQHZUmGq5FBtAmZ4&m=9pD2qNHBiPJscAs-ZzWT7q61NeZNcwsY8Io52JnaI3E&s=OaVJWcn8TI03qp9lgqeWMIVMySoyBIPowkHDEyR7lvQ&e=> >>> %indvars.iv.prol = phi i64 [ 0, %.lr.ph <https://urldefense.proofpoint.com/v2/url?u=http-3A__lr.ph&d=BQMFaQ&c=eEvniauFctOgLOKGJOplqw&r=v-ruWq0KCv2O3thJZiK6naxuXK8mQHZUmGq5FBtAmZ4&m=9pD2qNHBiPJscAs-ZzWT7q61NeZNcwsY8Io52JnaI3E&s=OaVJWcn8TI03qp9lgqeWMIVMySoyBIPowkHDEyR7lvQ&e=> ], [ %indvars.iv.next.prol, %3 ] >>> %prol.iter = phi i32 [ %xtraiter, %.lr.ph <https://urldefense.proofpoint.com/v2/url?u=http-3A__lr.ph&d=BQMFaQ&c=eEvniauFctOgLOKGJOplqw&r=v-ruWq0KCv2O3thJZiK6naxuXK8mQHZUmGq5FBtAmZ4&m=9pD2qNHBiPJscAs-ZzWT7q61NeZNcwsY8Io52JnaI3E&s=OaVJWcn8TI03qp9lgqeWMIVMySoyBIPowkHDEyR7lvQ&e=> ], [ %prol.iter.sub, %3 ] >>> %4 = getelementptr inbounds i32, i32* %array_x, i64 %indvars.iv.prol >>> %5 = trunc i64 %indvars.iv.prol to i32 >>> store i32 %5, i32* %4, align 4 >>> %indvars.iv.next.prol = add nuw nsw i64 %indvars.iv.prol, 1 >>> %lftr.wideiv.prol = trunc i64 %indvars.iv.next.prol to i32 >>> %exitcond.prol = icmp ne i32 %lftr.wideiv.prol, %n >>> %prol.iter.sub = sub i32 %prol.iter, 1 >>> %prol.iter.cmp = icmp ne i32 %prol.iter.sub, 0 >>> br i1 %prol.iter.cmp, label %3, label %.lr.ph.split, !llvm.loop !1 >>> >>> .lr.ph.split: ; preds = %3, %.lr.ph <https://urldefense.proofpoint.com/v2/url?u=http-3A__lr.ph&d=BQMFaQ&c=eEvniauFctOgLOKGJOplqw&r=v-ruWq0KCv2O3thJZiK6naxuXK8mQHZUmGq5FBtAmZ4&m=9pD2qNHBiPJscAs-ZzWT7q61NeZNcwsY8Io52JnaI3E&s=OaVJWcn8TI03qp9lgqeWMIVMySoyBIPowkHDEyR7lvQ&e=> >>> %indvars.iv.unr = phi i64 [ 0, %.lr.ph <https://urldefense.proofpoint.com/v2/url?u=http-3A__lr.ph&d=BQMFaQ&c=eEvniauFctOgLOKGJOplqw&r=v-ruWq0KCv2O3thJZiK6naxuXK8mQHZUmGq5FBtAmZ4&m=9pD2qNHBiPJscAs-ZzWT7q61NeZNcwsY8Io52JnaI3E&s=OaVJWcn8TI03qp9lgqeWMIVMySoyBIPowkHDEyR7lvQ&e=> ], [ %indvars.iv.next.prol, %3 ] >>> %6 = icmp ult i32 %2, 3 >>> br i1 %6, label %._crit_edge, label %.lr.ph.split.split >>> >>> .lr.ph.split.split: ; preds = %.lr.ph.split, %.lr.ph.split.split >>> %indvars.iv = phi i64 [ %indvars.iv.next.3, %.lr.ph.split.split ], [ %indvars.iv.unr, %.lr.ph.split ] >>> %7 = getelementptr inbounds i32, i32* %array_x, i64 %indvars.iv >>> %8 = trunc i64 %indvars.iv to i32 >>> store i32 %8, i32* %7, align 4 >>> %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1 >>> %lftr.wideiv = trunc i64 %indvars.iv.next to i32 >>> %9 = getelementptr inbounds i32, i32* %array_x, i64 %indvars.iv.next >>> %10 = trunc i64 %indvars.iv.next to i32 >>> store i32 %10, i32* %9, align 4 >>> %indvars.iv.next.1 = add nuw nsw i64 %indvars.iv.next, 1 >>> %lftr.wideiv.1 = trunc i64 %indvars.iv.next.1 to i32 >>> %11 = getelementptr inbounds i32, i32* %array_x, i64 %indvars.iv.next.1 >>> %12 = trunc i64 %indvars.iv.next.1 to i32 >>> store i32 %12, i32* %11, align 4 >>> %indvars.iv.next.2 = add nuw nsw i64 %indvars.iv.next.1, 1 >>> %lftr.wideiv.2 = trunc i64 %indvars.iv.next.2 to i32 >>> %13 = getelementptr inbounds i32, i32* %array_x, i64 %indvars.iv.next.2 >>> %14 = trunc i64 %indvars.iv.next.2 to i32 >>> store i32 %14, i32* %13, align 4 >>> %indvars.iv.next.3 = add nuw nsw i64 %indvars.iv.next.2, 1 >>> %lftr.wideiv.3 = trunc i64 %indvars.iv.next.3 to i32 >>> %exitcond.3 = icmp ne i32 %lftr.wideiv.3, %n >>> br i1 %exitcond.3, label %.lr.ph.split.split, label %._crit_edge >>> >>> ._crit_edge: ; preds = %.lr.ph.split, %.lr.ph.split.split, %0 >>> ret void >>> } >>> >>> attributes #0 = { nounwind uwtable "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-nans-fp-math"="false" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+sse,+sse2" "unsafe-fp-math"="false" "use-soft-float"="false" } >>> >>> !llvm.ident = !{!0} >>> >>> !0 = !{!"clang version 3.8.0 (trunk 245730) (llvm/trunk 245727)"} >>> !1 = distinct !{!1, !2} >>> !2 = !{!"llvm.loop.unroll.disable"} >>> >>> ******************************Clang Generate IR with LoopUnrolling End*********************************************** >>> >>> The second .bc file gives me this: >>> ******************************API Generate IR with LoopUnrolling Start************************************************* >>> ; ModuleID = 'bc_from_api.bc' >>> target triple = "x86_64-unkown-linux-gnu" >>> >>> ; Function Attrs: nounwind >>> define void @_Z3fooiPi(i32 %n, i32* %array_x) #0 { >>> entry: >>> %cmp.1 = icmp slt i32 0, %n >>> br i1 %cmp.1, label %for.body, label %for.end >>> >>> for.body: ; preds = %entry, %for.body.3 >>> %i.02 = phi i32 [ %inc.3, %for.body.3 ], [ 0, %entry ] >>> %idxprom = sext i32 %i.02 to i64 >>> %arrayidx = getelementptr inbounds i32, i32* %array_x, i64 %idxprom >>> store i32 %i.02, i32* %arrayidx, align 4 >>> %inc = add nuw nsw i32 %i.02, 1 >>> %cmp = icmp slt i32 %inc, %n >>> br i1 %cmp, label %for.body.1, label %for.end >>> >>> for.end: ; preds = %for.body, %for.body.1, %for.body.2, %for.body.3, %entry >>> ret void >>> >>> for.body.1: ; preds = %for.body >>> %idxprom.1 = sext i32 %inc to i64 >>> %arrayidx.1 = getelementptr inbounds i32, i32* %array_x, i64 %idxprom.1 >>> store i32 %inc, i32* %arrayidx.1, align 4 >>> %inc.1 = add nuw nsw i32 %inc, 1 >>> %cmp.1.3 = icmp slt i32 %inc.1, %n >>> br i1 %cmp.1.3, label %for.body.2, label %for.end >>> >>> for.body.2: ; preds = %for.body.1 >>> %idxprom.2 = sext i32 %inc.1 to i64 >>> %arrayidx.2 = getelementptr inbounds i32, i32* %array_x, i64 %idxprom.2 >>> store i32 %inc.1, i32* %arrayidx.2, align 4 >>> %inc.2 = add nuw nsw i32 %inc.1, 1 >>> %cmp.2 = icmp slt i32 %inc.2, %n >>> br i1 %cmp.2, label %for.body.3, label %for.end >>> >>> for.body.3: ; preds = %for.body.2 >>> %idxprom.3 = sext i32 %inc.2 to i64 >>> %arrayidx.3 = getelementptr inbounds i32, i32* %array_x, i64 %idxprom.3 >>> store i32 %inc.2, i32* %arrayidx.3, align 4 >>> %inc.3 = add nuw nsw i32 %inc.2, 1 >>> %cmp.3 = icmp slt i32 %inc.3, %n >>> br i1 %cmp.3, label %for.body, label %for.end >>> } >>> >>> attributes #0 = { nounwind } >>> ******************************API Generate IR with LoopUnrolling End************************************************** >>> >>> Sorry I post two many code here. Can you give me any suggestion? >> >> Yes, use an online service like pastebin :) >> >> You don’t have defined the DataLayout in the API cases, it should help to do so. >> >> — >> Mehdi >> >> > > _______________________________________________ > LLVM Developers mailing list > llvm-dev at lists.llvm.org > https://urldefense.proofpoint.com/v2/url?u=http-3A__lists.llvm.org_cgi-2Dbin_mailman_listinfo_llvm-2Ddev&d=BQIGaQ&c=eEvniauFctOgLOKGJOplqw&r=ygVmcuuQ1MUhRUoJm-IgPtgjmvM0byfjlHDg99vufEI&m=fTaYh_3htnphmYaZnIJ7RlD2zF78C946V9piONj6elY&s=oufO2GrLzz_kSSL7lrubmFJRhih1i0Yx3y5AHMx81pE&e= <https://urldefense.proofpoint.com/v2/url?u=http-3A__lists.llvm.org_cgi-2Dbin_mailman_listinfo_llvm-2Ddev&d=BQIGaQ&c=eEvniauFctOgLOKGJOplqw&r=ygVmcuuQ1MUhRUoJm-IgPtgjmvM0byfjlHDg99vufEI&m=fTaYh_3htnphmYaZnIJ7RlD2zF78C946V9piONj6elY&s=oufO2GrLzz_kSSL7lrubmFJRhih1i0Yx3y5AHMx81pE&e=>-------------- next part -------------- An HTML attachment was scrubbed... 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