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<p class="MsoNormal">It looks like the runtime unroll does not support the trip count with pointer type…<o:p></o:p></p>

<p class="MsoNormal">Before handling the multiple exits, I need to resolve it first for my example…<o:p></o:p></p>

<p class="MsoNormal">If possible, can someone let me know that people are working on it or there are reviews for it on phabricator please?<o:p></o:p></p>

<p class="MsoNormal"><o:p> </o:p></p>

<p class="MsoNormal">Thanks<o:p></o:p></p>

<p class="MsoNormal">JinGu Kang<o:p></o:p></p>

<p class="MsoNormal"><o:p> </o:p></p>

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<p class="MsoNormal"><b>From:</b> llvm-dev <llvm-dev-bounces@lists.llvm.org> <b>On Behalf Of

</b>Jingu Kang via llvm-dev<br>

<b>Sent:</b> 21 July 2021 09:51<br>

<b>To:</b> Philip Reames <listmail@philipreames.com><br>

<b>Cc:</b> llvm-dev@lists.llvm.org<br>

<b>Subject:</b> Re: [llvm-dev] Question about Unrolling Loop with Multiple Exits<o:p></o:p></p>

</div>

</div>

<p class="MsoNormal"><o:p> </o:p></p>

<p class="MsoNormal">Thanks for kind suggestion Philip.<o:p></o:p></p>

<p class="MsoNormal"><o:p> </o:p></p>

<p class="MsoNormal">Let me have a look at the points where the debug message mentions.<o:p></o:p></p>

<p class="MsoNormal"><o:p> </o:p></p>

<p class="MsoNormal">Regards<o:p></o:p></p>

<p class="MsoNormal">JinGu Kang<o:p></o:p></p>

<p class="MsoNormal"><o:p> </o:p></p>

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<p class="MsoNormal"><b>From:</b> llvm-dev <<a href="mailto:llvm-dev-bounces@lists.llvm.org">llvm-dev-bounces@lists.llvm.org</a>>

<b>On Behalf Of </b>Philip Reames via llvm-dev<br>

<b>Sent:</b> 20 July 2021 18:17<br>

<b>To:</b> Jingu Kang <<a href="mailto:Jingu.Kang@arm.com">Jingu.Kang@arm.com</a>><br>

<b>Cc:</b> <a href="mailto:llvm-dev@lists.llvm.org">llvm-dev@lists.llvm.org</a><br>

<b>Subject:</b> Re: [llvm-dev] Question about Unrolling Loop with Multiple Exits<o:p></o:p></p>

</div>

</div>

<p class="MsoNormal"><o:p> </o:p></p>

<p class="MsoNormal">./opt -loop-unrollï¿½ -enable-new-pm=0 < llvm-dev.ll -S -unroll-runtime -debug<br>

Args: ./opt -loop-unroll -enable-new-pm=0 -S -unroll-runtime -debug <br>

Loop Unroll: F[test] Loop %while.body.us<br>

ï¿½ Loop Size = 10<br>

ï¿½ runtime unrolling with count: 8<br>

ï¿½ Exiting block %if.end8.us: TripCount=0, TripMultiple=1, BreakoutTrip=1<br>

ï¿½ Exiting block %while.cond.backedge: TripCount=0, TripMultiple=1, BreakoutTrip=1<br>

Trying runtime unrolling on Loop: <br>

Loop at depth 1 containing: %while.body.us<header>,%if.end8.us<exiting>,%while.cond.backedge<latch><exiting><br>

Using prolog remainder.<br>

Bailout for multi-exit handling when latch exit has >1 predecessor.<br>

Multiple exit/exiting blocks in loop and multi-exit unrolling not enabled!<br>

Won't unroll; remainder loop could not be generated when assuming runtime trip count<br>

; ModuleID = '<stdin>'<br>

source_filename = "<stdin>"<br>

<br>

declare i32 @foo(i8*)<br>

<br>

define void @test(i8* %s, i64 %a) {<br>

entry:<br>

ï¿½ %s.addr.a = getelementptr i8, i8* %s, i64 %a<br>

ï¿½ br label %while.body.us<br>

<br>

while.body.us:ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ ; preds = %while.cond.backedge, %entry<br>

ï¿½ %s.addr = phi i8* [ %incdec.ptr, %while.cond.backedge ], [ %s, %entry ]<br>

ï¿½ %incdec.ptr = getelementptr inbounds i8, i8* %s.addr, i64 1<br>

ï¿½ %incdec.val = load i8, i8* %s.addr, align 1<br>

ï¿½ %cmp1 = icmp eq i8 %incdec.val, 10<br>

ï¿½ br i1 %cmp1, label %if.end8.us, label %while.cond.backedge<br>

<br>

if.end8.us:ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ ; preds = %while.body.us<br>

ï¿½ %call9 = tail call i32 @foo(i8* nonnull %incdec.ptr)<br>

ï¿½ %cmp2 = icmp ult i32 %call9, 0<br>

ï¿½ br i1 %cmp2, label %while.cond.backedge, label %return.loopexit<br>

<br>

while.cond.backedge:ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ ; preds = %if.end8.us, %while.body.us<br>

ï¿½ %cmp3 = icmp eq i8* %incdec.ptr, %s.addr.a<br>

ï¿½ br i1 %cmp3, label %return.loopexit, label %while.body.us<br>

<br>

return.loopexit:ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ ; preds = %while.cond.backedge, %if.end8.us<br>

ï¿½ ret void<br>

}<o:p></o:p></p>

<p>The debug output appears to give a pretty good clue as to where you could start if desired.<o:p></o:p></p>

<p>Philip<o:p></o:p></p>

<div>

<p class="MsoNormal">On 7/20/21 9:45 AM, Jingu Kang wrote:<o:p></o:p></p>

</div>

<blockquote style="margin-top:5.0pt;margin-bottom:5.0pt">

<p class="MsoNormal">Hi Philip,<o:p></o:p></p>

<p class="MsoNormal">ï¿½<o:p></o:p></p>

<p class="MsoNormal">I have reduced the test case roughly as below.<o:p></o:p></p>

<p class="MsoNormal">ï¿½<o:p></o:p></p>

<p class="MsoNormal">declare i32 @foo(i8 *)<o:p></o:p></p>

<p class="MsoNormal">ï¿½<o:p></o:p></p>

<p class="MsoNormal">define void @test(i8* %s, i64 %a) {<o:p></o:p></p>

<p class="MsoNormal">entry:<o:p></o:p></p>

<p class="MsoNormal">ï¿½ %s.addr.a = getelementptr i8, i8* %s, i64 %a<o:p></o:p></p>

<p class="MsoNormal">ï¿½ br label %while.body.us<o:p></o:p></p>

<p class="MsoNormal">ï¿½<o:p></o:p></p>

<p class="MsoNormal">while.body.us:ï¿½ï¿½ï¿½ <o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½%s.addr = phi i8* [ %incdec.ptr, %while.cond.backedge ], [ %s, %entry ]<o:p></o:p></p>

<p class="MsoNormal">ï¿½ %incdec.ptr = getelementptr inbounds i8, i8* %s.addr, i64 1<o:p></o:p></p>

<p class="MsoNormal">ï¿½ %incdec.val = load i8, i8* %s.addr, align 1<o:p></o:p></p>

<p class="MsoNormal">ï¿½ %cmp1 = icmp eq i8 %incdec.val, 10<o:p></o:p></p>

<p class="MsoNormal">ï¿½ br i1 %cmp1, label %if.end8.us, label %while.cond.backedge<o:p></o:p></p>

<p class="MsoNormal">ï¿½<o:p></o:p></p>

<p class="MsoNormal">if.end8.us:ï¿½ï¿½ï¿½ <o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½%call9 = tail call i32 @foo(i8* nonnull %incdec.ptr)<o:p></o:p></p>

<p class="MsoNormal">ï¿½ %cmp2 = icmp ult i32 %call9, 0<o:p></o:p></p>

<p class="MsoNormal">ï¿½ br i1 %cmp2, label %while.cond.backedge, label %return.loopexit<o:p></o:p></p>

<p class="MsoNormal">ï¿½<o:p></o:p></p>

<p class="MsoNormal">while.cond.backedge:<o:p></o:p></p>

<p class="MsoNormal">ï¿½ %cmp3 = icmp eq i8* %incdec.ptr, %s.addr.a<o:p></o:p></p>

<p class="MsoNormal">ï¿½ br i1 %cmp3, label %return.loopexit, label %while.body.us<o:p></o:p></p>

<p class="MsoNormal">ï¿½<o:p></o:p></p>

<p class="MsoNormal">return.loopexit:ï¿½ï¿½ï¿½ <o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ret void<o:p></o:p></p>

<p class="MsoNormal">}<o:p></o:p></p>

<p class="MsoNormal">ï¿½<o:p></o:p></p>

<p class="MsoNormal">Roughly, I unrolled the loop manually 2 times as below and ignored the remaining loop simply.<o:p></o:p></p>

<p class="MsoNormal">ï¿½<o:p></o:p></p>

<p class="MsoNormal">define void @test(i8* %s, i64 %a) {<o:p></o:p></p>

<p class="MsoNormal">entry:<o:p></o:p></p>

<p class="MsoNormal">ï¿½ %s.addr.a = getelementptr i8, i8* %s, i64 %a<o:p></o:p></p>

<p class="MsoNormal">ï¿½ br label %while.body.us<o:p></o:p></p>

<p class="MsoNormal">ï¿½<o:p></o:p></p>

<p class="MsoNormal">while.body.us:ï¿½ï¿½ï¿½ <o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½%s.addr = phi i8* [ %incdec.ptr, %while.cond.backedge ], [ %s, %entry ]<o:p></o:p></p>

<p class="MsoNormal">ï¿½ %incdec.ptr = getelementptr inbounds i8, i8* %s.addr, i64 1<o:p></o:p></p>

<p class="MsoNormal">ï¿½ %incdec.val = load i8, i8* %s.addr, align 1<o:p></o:p></p>

<p class="MsoNormal">ï¿½ %cmp1 = icmp eq i8 %incdec.val, 10<o:p></o:p></p>

<p class="MsoNormal">ï¿½ br i1 %cmp1, label %if.end8.us, label %while.body.us.1<o:p></o:p></p>

<p class="MsoNormal">ï¿½<o:p></o:p></p>

<p class="MsoNormal">while.body.us.1:ï¿½ï¿½ï¿½ <o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½%incdec.ptr.1 = getelementptr inbounds i8, i8* %incdec.ptr, i64 1<o:p></o:p></p>

<p class="MsoNormal">ï¿½ %incdec.val.1 = load i8, i8* %incdec.ptr, align 1<o:p></o:p></p>

<p class="MsoNormal">ï¿½ %cmp1.1 = icmp eq i8 %incdec.val.1, 10<o:p></o:p></p>

<p class="MsoNormal">ï¿½ br i1 %cmp1.1, label %if.end8.us, label %while.cond.backedge<o:p></o:p></p>

<p class="MsoNormal">ï¿½<o:p></o:p></p>

<p class="MsoNormal">if.end8.us:ï¿½ï¿½ï¿½ <o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½%incdec.ptr.phi = phi i8* [ %incdec.ptr, %while.body.us ], [ %incdec.ptr.1, %while.body.us.1 ]<o:p></o:p></p>

<p class="MsoNormal">ï¿½ %call9 = tail call i32 @foo(i8* nonnull %incdec.ptr.phi)<o:p></o:p></p>

<p class="MsoNormal">ï¿½ %cmp2 = icmp ult i32 %call9, 0<o:p></o:p></p>

<p class="MsoNormal">ï¿½ br i1 %cmp2, label %while.cond.backedge, label %return.loopexit<o:p></o:p></p>

<p class="MsoNormal">ï¿½<o:p></o:p></p>

<p class="MsoNormal">while.cond.backedge:<o:p></o:p></p>

<p class="MsoNormal">ï¿½ %cmp3 = icmp eq i8* %incdec.ptr.1, %s.addr.a<o:p></o:p></p>

<p class="MsoNormal">ï¿½ br i1 %cmp3, label %return.loopexit, label %while.body.us<o:p></o:p></p>

<p class="MsoNormal">ï¿½<o:p></o:p></p>

<p class="MsoNormal">return.loopexit:ï¿½ï¿½ï¿½ <o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ret void<o:p></o:p></p>

<p class="MsoNormal">}<o:p></o:p></p>

<p class="MsoNormal">ï¿½<o:p></o:p></p>

<p class="MsoNormal">If possible, can we make loop unroll pass handle this kind of cases please?<o:p></o:p></p>

<p class="MsoNormal">If I missed something, please let me know.<o:p></o:p></p>

<p class="MsoNormal">ï¿½<o:p></o:p></p>

<p class="MsoNormal">Thanks<o:p></o:p></p>

<p class="MsoNormal">JinGu Kang<o:p></o:p></p>

<p class="MsoNormal">ï¿½<o:p></o:p></p>

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<div style="border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0cm 0cm 0cm">

<p class="MsoNormal"><b>From:</b> llvm-dev <a href="mailto:llvm-dev-bounces@lists.llvm.org">

<llvm-dev-bounces@lists.llvm.org></a> <b>On Behalf Of </b>Philip Reames via llvm-dev<br>

<b>Sent:</b> 16 July 2021 20:12<br>

<b>To:</b> Jingu Kang <a href="mailto:Jingu.Kang@arm.com"><Jingu.Kang@arm.com></a><br>

<b>Cc:</b> <a href="mailto:llvm-dev@lists.llvm.org">llvm-dev@lists.llvm.org</a><br>

<b>Subject:</b> Re: [llvm-dev] Question about Unrolling Loop with Multiple Exits<o:p></o:p></p>

</div>

</div>

<p class="MsoNormal">ï¿½<o:p></o:p></p>

<p>Jingu,<o:p></o:p></p>

<p>I'm not fluent in AArch64 assembly, sorry.ï¿½ If you want more meaningful commentary, you'll need to reduce your c++ example further, and give a better explanation of what you expect the unroller to do for you.ï¿½

<o:p></o:p></p>

<p>Philip<o:p></o:p></p>

<div>

<p class="MsoNormal">On 7/16/21 12:09 PM, Jingu Kang wrote:<o:p></o:p></p>

</div>

<blockquote style="margin-top:5.0pt;margin-bottom:5.0pt">

<p class="MsoNormal">Sorry for poor exampleï¿½<o:p></o:p></p>

<p class="MsoNormal">ï¿½<o:p></o:p></p>

<p class="MsoNormal">The AArch64 assembly output of the example from gcc is as below. The loop is unrolled 7 times. I have written some comments to explain how the assembly code is mapped to C source code. As you can see on `.L3` label, the ï¿½if (*s++ != '\n')ï¿½

 block is unrolled 7 times. <o:p></o:p></p>

<p class="MsoNormal">ï¿½<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ stpï¿½ï¿½ï¿½ï¿½ x29, x30, [sp, -48]!<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ movï¿½ï¿½ï¿½ï¿½ x29, sp<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ stpï¿½ï¿½ï¿½ï¿½ x19, x20, [sp, 16]<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ movï¿½ï¿½ï¿½ï¿½ x19, x0ï¿½ --> x19 is char *s<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ movï¿½ï¿½ï¿½ï¿½ x20, x1ï¿½ --> x20 is char *end<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ strï¿½ï¿½ï¿½ï¿½ x21, [sp, 32]<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ orrï¿½ï¿½ï¿½ï¿½ x21, x3, x2ï¿½ --> x21 is check1 | check2<o:p></o:p></p>

<p class="MsoNormal">.L70:<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ subï¿½ï¿½ï¿½ï¿½ x0, x20, x19ï¿½ --> x0 = end - s;<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ addï¿½ï¿½ï¿½ï¿½ x1, x0, 1<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ andsï¿½ï¿½ï¿½ x2, x1, 7ï¿½ --> unroll count is 7<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ beqï¿½ï¿½ï¿½ï¿½ .L3ï¿½ï¿½ï¿½ï¿½ --> .L3 is inside while loop. if (*s++ != '\n')<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ cmpï¿½ï¿½ï¿½ï¿½ x19, x20 ï¿½--> while(s <= end)<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ bhiï¿½ï¿½ï¿½ï¿½ .L2ï¿½ï¿½ï¿½ï¿½ --> .L2 is label ret1.<o:p></o:p></p>

<p class="MsoNormal">ï¿½<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ ldrbï¿½ï¿½ï¿½ w3, [x19], 1ï¿½ --> start of remainder<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ cmpï¿½ï¿½ï¿½ï¿½ w3, 10<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ beqï¿½ï¿½ï¿½ï¿½ .L71<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ cmpï¿½ï¿½ï¿½ï¿½ x2, 1<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ beqï¿½ï¿½ï¿½ï¿½ .L3<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ cmpï¿½ï¿½ï¿½ï¿½ x2, 2<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ beqï¿½ï¿½ï¿½ï¿½ .L49<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ cmpï¿½ï¿½ï¿½ï¿½ x2, 3<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ beqï¿½ï¿½ï¿½ï¿½ .L50<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ cmpï¿½ï¿½ï¿½ï¿½ x2, 4<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ beqï¿½ï¿½ï¿½ï¿½ .L51<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ cmpï¿½ï¿½ï¿½ï¿½ x2, 5<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ beqï¿½ï¿½ï¿½ï¿½ .L52<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ cmpï¿½ï¿½ï¿½ï¿½ x2, 6<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ beqï¿½ï¿½ï¿½ï¿½ .L53<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ ldrbï¿½ï¿½ï¿½ w4, [x19], 1<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ cmpï¿½ï¿½ï¿½ï¿½ w4, 10<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ bneï¿½ï¿½ï¿½ï¿½ .L53<o:p></o:p></p>

<p class="MsoNormal">.L71:<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ cbzï¿½ï¿½ï¿½ï¿½ x21, .L4ï¿½ --> if(check1 || check2)<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ blï¿½ï¿½ï¿½ï¿½ï¿½ foo()<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ movï¿½ï¿½ï¿½ï¿½ x19, x0<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ cbzï¿½ï¿½ï¿½ï¿½ x0, .L2ï¿½ï¿½ --> if (!s) goto ret1;<o:p></o:p></p>

<p class="MsoNormal">ï¿½<o:p></o:p></p>

<p class="MsoNormal">.L4:ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ --> if(boo(s)) goto ret0;<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ movï¿½ï¿½ï¿½ï¿½ x0, x19<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ ï¿½ï¿½blï¿½ï¿½ï¿½ï¿½ï¿½ boo(char*)<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ cbzï¿½ï¿½ï¿½ï¿½ w0, .L70<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ movï¿½ï¿½ï¿½ï¿½ w0, 0<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ ldpï¿½ï¿½ï¿½ï¿½ x19, x20, [sp, 16]<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ ldrï¿½ï¿½ï¿½ï¿½ x21, [sp, 32]<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ ldpï¿½ï¿½ï¿½ï¿½ x29, x30, [sp], 48<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ ret<o:p></o:p></p>

<p class="MsoNormal">.L53:ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ --> if (*s++ != '\n') for remainder<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ ldrbï¿½ï¿½ï¿½ w5, [x19], 1<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ cmpï¿½ï¿½ï¿½ï¿½ w5, 10<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ beqï¿½ï¿½ï¿½ï¿½ .L71<o:p></o:p></p>

<p class="MsoNormal">.L52:ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ --> if (*s++ != '\n') for remainder<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ ldrbï¿½ï¿½ï¿½ w6, [x19], 1<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ cmpï¿½ï¿½ï¿½ï¿½ w6, 10<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ beqï¿½ï¿½ï¿½ï¿½ .L71<o:p></o:p></p>

<p class="MsoNormal">.L51:ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ --> if (*s++ != '\n') for remainder<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ ldrbï¿½ï¿½ï¿½ w7, [x19], 1<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ cmpï¿½ï¿½ï¿½ï¿½ w7, 10<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ beqï¿½ï¿½ï¿½ï¿½ .L71<o:p></o:p></p>

<p class="MsoNormal">.L50:ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ --> if (*s++ != '\n') for remainder<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ ldrbï¿½ï¿½ï¿½ w8, [x19], 1<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ cmpï¿½ï¿½ï¿½ï¿½ w8, 10<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ beqï¿½ï¿½ï¿½ï¿½ .L71<o:p></o:p></p>

<p class="MsoNormal">.L49:ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ --> if (*s++ != '\n') for remainder<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ ldrbï¿½ï¿½ï¿½ w9, [x19], 1<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ cmpï¿½ï¿½ï¿½ï¿½ w9, 10<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ beqï¿½ï¿½ï¿½ï¿½ .L71<o:p></o:p></p>

<p class="MsoNormal">.L3:ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ --> if (*s++ != '\n'), 7 times unrolled<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ cmpï¿½ï¿½ï¿½ï¿½ x19, x20<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ bhiï¿½ï¿½ï¿½ï¿½ .L2<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ ldrbï¿½ï¿½ï¿½ w10, [x19]<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ addï¿½ï¿½ ï¿½ï¿½x19, x19, 1<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ movï¿½ï¿½ï¿½ï¿½ x11, x19<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ cmpï¿½ï¿½ï¿½ï¿½ w10, 10<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ beqï¿½ï¿½ï¿½ï¿½ .L71<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ ldrbï¿½ï¿½ï¿½ w12, [x19], 1<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ cmpï¿½ï¿½ï¿½ï¿½ w12, 10<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ beqï¿½ï¿½ï¿½ï¿½ .L71<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ ldrbï¿½ï¿½ï¿½ w13, [x11, 1]<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ addï¿½ï¿½ï¿½ï¿½ x19, x11, 2<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ cmpï¿½ï¿½ï¿½ï¿½ w13, 10<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ beqï¿½ï¿½ï¿½ ï¿½.L71<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ ldrbï¿½ï¿½ï¿½ w14, [x11, 2]<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ addï¿½ï¿½ï¿½ï¿½ x19, x11, 3<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ cmpï¿½ï¿½ï¿½ï¿½ w14, 10<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ beqï¿½ï¿½ï¿½ï¿½ .L71<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ ldrbï¿½ï¿½ï¿½ w15, [x11, 3]<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ addï¿½ï¿½ï¿½ï¿½ x19, x11, 4<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ cmpï¿½ï¿½ï¿½ï¿½ w15, 10<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ beqï¿½ï¿½ï¿½ï¿½ .L71<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ ldrbï¿½ï¿½ï¿½ w16, [x11, 4]<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ addï¿½ï¿½ï¿½ï¿½ x19, x11, 5<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ cmpï¿½ï¿½ï¿½ï¿½ w16, 10<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ beqï¿½ï¿½ï¿½ï¿½ .L71<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ ldrbï¿½ï¿½ï¿½ w17, [x11, 5]<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ addï¿½ï¿½ï¿½ï¿½ x19, x11, 6<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ cmpï¿½ï¿½ï¿½ï¿½ w17, 10<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ beqï¿½ï¿½ï¿½ï¿½ .L71<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ ldrbï¿½ï¿½ï¿½ w18, [x11, 6]<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ addï¿½ï¿½ï¿½ï¿½ x19, x11, 7<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ cmpï¿½ï¿½ï¿½ï¿½ w18, 10<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ beqï¿½ï¿½ï¿½ï¿½ .L71<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ bï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ .L3<o:p></o:p></p>

<p class="MsoNormal">.L2:ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ --> label ret1<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ movï¿½ï¿½ï¿½ï¿½ w0, 1<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ ldpï¿½ï¿½ï¿½ï¿½ x19, x20, [sp, 16]<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ ldrï¿½ï¿½ï¿½ï¿½ x21, [sp, 32]<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ ldpï¿½ï¿½ï¿½ï¿½ x29, x30, [sp], 48<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ ret<o:p></o:p></p>

<p class="MsoNormal">ï¿½<o:p></o:p></p>

<p class="MsoNormal">I am sorry for showing you assembly output directlyï¿½ It looks like the rtl levelï¿½s unroll pass of gcc unrolls above loop and I need to check it next week. Once I have clear idea about above unrolling from gcc, let me reduce the example

 more and let you know. <o:p></o:p></p>

<p class="MsoNormal">ï¿½<o:p></o:p></p>

<p class="MsoNormal">Thanks<o:p></o:p></p>

<p class="MsoNormal">JinGu Kang<o:p></o:p></p>

<p class="MsoNormal">ï¿½<o:p></o:p></p>

<div style="border:none;border-left:solid blue 1.5pt;padding:0cm 0cm 0cm 4.0pt">

<div>

<div style="border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0cm 0cm 0cm">

<p class="MsoNormal"><b>From:</b> llvm-dev <a href="mailto:llvm-dev-bounces@lists.llvm.org">

<llvm-dev-bounces@lists.llvm.org></a> <b>On Behalf Of </b>Philip Reames via llvm-dev<br>

<b>Sent:</b> 16 July 2021 18:27<br>

<b>To:</b> Jingu Kang <a href="mailto:Jingu.Kang@arm.com"><Jingu.Kang@arm.com></a><br>

<b>Cc:</b> <a href="mailto:llvm-dev@lists.llvm.org">llvm-dev@lists.llvm.org</a><br>

<b>Subject:</b> Re: [llvm-dev] Question about Unrolling Loop with Multiple Exits<o:p></o:p></p>

</div>

</div>

<p class="MsoNormal">ï¿½<o:p></o:p></p>

<p>ï¿½<o:p></o:p></p>

<div>

<p class="MsoNormal">On 7/16/21 9:29 AM, Jingu Kang wrote:<o:p></o:p></p>

</div>

<blockquote style="margin-top:5.0pt;margin-bottom:5.0pt">

<p>Hi Philip,<o:p></o:p></p>

<p>Thanks for your kind reply.<o:p></o:p></p>

<p>> A) Are you measuring on tip of tree?ï¿½ There were changes for multiple exit unrolling which landed very recently.<o:p></o:p></p>

<p>Yep, I am investigating benchmarks with llvm tip and I can see the llvm fails to unroll some loops with multiple exits.<o:p></o:p></p>

<p class="MsoNormal">> B) One of your exits does not dominate your latch.ï¿½ Those are generally hard<o:p></o:p></p>

<p class="MsoNormal">> C) This example does not seem to require gotos.ï¿½ I strongly suggest reducing your test cases if you want more informed commentary.ï¿½<o:p></o:p></p>

<p class="MsoNormal">ï¿½<o:p></o:p></p>

<p class="MsoNormal">I am looking at perlbench recently and it has `goto` statements inside loop. The example is a reduced case.

<o:p></o:p></p>

</blockquote>

<p class="MsoNormal" style="margin-bottom:12.0pt">Right, but the gotos aren't relevant for your reduced test.ï¿½ You can reduce further.<br>

<br>

<br>

<o:p></o:p></p>

<blockquote style="margin-top:5.0pt;margin-bottom:5.0pt">

<p class="MsoNormal">When I look at the gccï¿½s output of the example, it looks like gcc unrolls only the below `if` statement blockï¿½<o:p></o:p></p>

<p class="MsoNormal">ï¿½<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ if (*s++ != '\n')<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ continue;<o:p></o:p></p>

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<p class="MsoNormal" style="margin-bottom:12.0pt">Your phrasing here does not parse for me.ï¿½ Can you restate this with different wording and maybe a fully worked example?<br>

<br>

<br>

<o:p></o:p></p>

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<p class="MsoNormal">ï¿½<o:p></o:p></p>

<p class="MsoNormal">Thanks<o:p></o:p></p>

<p class="MsoNormal">JinGu Kang<o:p></o:p></p>

<p class="MsoNormal">ï¿½<o:p></o:p></p>

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<p class="MsoNormal"><b>From:</b> llvm-dev <a href="mailto:llvm-dev-bounces@lists.llvm.org">

<llvm-dev-bounces@lists.llvm.org></a> <b>On Behalf Of </b>Philip Reames via llvm-dev<br>

<b>Sent:</b> 16 July 2021 15:52<br>

<b>To:</b> Jingu Kang <a href="mailto:Jingu.Kang@arm.com"><Jingu.Kang@arm.com></a>;

<a href="mailto:llvm-dev@lists.llvm.org">llvm-dev@lists.llvm.org</a><br>

<b>Subject:</b> Re: [llvm-dev] Question about Unrolling Loop with Multiple Exits<o:p></o:p></p>

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<p class="MsoNormal">ï¿½<o:p></o:p></p>

<p>A) Are you measuring on tip of tree?ï¿½ There were changes for multiple exit unrolling which landed very recently.<o:p></o:p></p>

<p>B) One of your exits does not dominate your latch.ï¿½ Those are generally hard.ï¿½

<o:p></o:p></p>

<p>C) This example does not seem to require gotos.ï¿½ I strongly suggest reducing your test cases if you want more informed commentary.ï¿½

<o:p></o:p></p>

<p>Philip<o:p></o:p></p>

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<p class="MsoNormal">On 7/16/21 7:42 AM, Jingu Kang via llvm-dev wrote:<o:p></o:p></p>

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<p class="MsoNormal">Hi All,<o:p></o:p></p>

<p class="MsoNormal">ï¿½<o:p></o:p></p>

<p class="MsoNormal">While I am investigating benchmarks, I have found loops which llvm fails to unroll because the loops have multiple exits.<o:p></o:p></p>

<p class="MsoNormal">For example, <o:p></o:p></p>

<p class="MsoNormal">ï¿½<o:p></o:p></p>

<p class="MsoNormal">char *foo(void);<o:p></o:p></p>

<p class="MsoNormal">int boo(char *s);<o:p></o:p></p>

<p class="MsoNormal">ï¿½<o:p></o:p></p>

<p class="MsoNormal">int test(char *s, char *end, char *check1, char *check2) {<o:p></o:p></p>

<p class="MsoNormal">ï¿½ while (s <= end) {<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ if (*s++ != '\n')<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ continue;<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ if (check1 || check2) {<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ s = foo();<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ if (!s)<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ goto ret1;<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ }ï¿½ï¿½ <o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½if (boo(s))<o:p></o:p></p>

<p class="MsoNormal">ï¿½ï¿½ï¿½ï¿½ï¿½ goto ret0;<o:p></o:p></p>

<p class="MsoNormal">ï¿½ }<o:p></o:p></p>

<p class="MsoNormal">ï¿½ goto ret1;<o:p></o:p></p>

<p class="MsoNormal">ï¿½<o:p></o:p></p>

<p class="MsoNormal">ret0:<o:p></o:p></p>

<p class="MsoNormal">ï¿½ return 0;<o:p></o:p></p>

<p class="MsoNormal">ret1:<o:p></o:p></p>

<p class="MsoNormal">ï¿½ return 1;<o:p></o:p></p>

<p class="MsoNormal">}<o:p></o:p></p>

<p class="MsoNormal">ï¿½<o:p></o:p></p>

<p class="MsoNormal">Above code causes below messages from LoopUnroll pass.<o:p></o:p></p>

<p class="MsoNormal">ï¿½<o:p></o:p></p>

<p class="MsoNormal">Bailout for multi-exit handling when latch exit has >1 predecessor.<o:p></o:p></p>

<p class="MsoNormal">Multiple exit/exiting blocks in loop and multi-exit unrolling not enabled!<o:p></o:p></p>

<p class="MsoNormal">ï¿½<o:p></o:p></p>

<p class="MsoNormal">I can see the option `unroll-runtime-multi-exit` and comments about it. I wonder there are already reviews for the work on phabriactor or some people are working on it.<o:p></o:p></p>

<p class="MsoNormal">If someone knows information about it, please share it.<o:p></o:p></p>

<p class="MsoNormal">ï¿½<o:p></o:p></p>

<p class="MsoNormal">Thanks<o:p></o:p></p>

<p class="MsoNormal">JinGu Kang<o:p></o:p></p>

<p class="MsoNormal">ï¿½<o:p></o:p></p>

<p class="MsoNormal">ï¿½<o:p></o:p></p>

<p class="MsoNormal">ï¿½<o:p></o:p></p>

<p class="MsoNormal">ï¿½<o:p></o:p></p>

<p class="MsoNormal">ï¿½<o:p></o:p></p>

<p class="MsoNormal">ï¿½<o:p></o:p></p>

<p class="MsoNormal" style="margin-bottom:12.0pt"><br>

<br>

<br>

<br>

<o:p></o:p></p>

<pre>_______________________________________________<o:p></o:p></pre>

<pre>LLVM Developers mailing list<o:p></o:p></pre>

<pre><a href="mailto:llvm-dev@lists.llvm.org">llvm-dev@lists.llvm.org</a><o:p></o:p></pre>

<pre><a href="https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev">https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev</a><o:p></o:p></pre>

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