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<p class="MsoNormal">Hi Stefanos,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Attached the testcase. I tried to reduce it further, but the problem goes away when I remove the instructions further.<o:p></o:p></p>
<p class="MsoNormal">There is a nested loop and the fault occurs while processing the inner loop (for.body)<o:p></o:p></p>
<p class="MsoNormal">To reproduce the crash: <o:p></o:p></p>
<p class="MsoNormal"> opt -O3 testcase.ll -o out.ll<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">> `groupChecks()` will only try to group pointers that are on the same alias set.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">If that’s true, the RT check should have been prevented for these pointers in question.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><b>Additional details about the problem:<o:p></o:p></b></p>
<p class="MsoNormal"> The crash first appeared after the following llvm commit to preserve the Global AA.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal" style="margin-left:.5in">commit e6cf796bab7e02d2b8ac7fd495f14f5e21494270<o:p></o:p></p>
<p class="MsoNormal" style="margin-left:.5in">Author: Ryan Santhiraraja <rsanthir@quicinc.com><o:p></o:p></p>
<p class="MsoNormal" style="margin-left:.5in">Date: Thu Jul 2 13:53:20 2020 +0100<o:p></o:p></p>
<p class="MsoNormal" style="margin-left:.5in"> Preserve GlobalsAA analysis result in LowerConstantIntrinsics<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">The Global AA now finds out that these pointers refer different objects and won’t alias each other, and eventually ended up in different alias sets.<o:p></o:p></p>
<p class="MsoNormal">Prior to this commit, none of the alias analysis could appropriate the noAlias property for these pointers. (If you revert this patch locally, the testcase will compile successfully).<o:p></o:p></p>
<p class="MsoNormal">The address-space validation (given below) prevented the RT check for these pointers earlier which I expected even to get triggered with the upstream compiler today.<o:p></o:p></p>
<p class="MsoNormal">But it didn’t occur as they have the same DependenceSetId value. (The DependenceSetId starts from 1 for each Alias Set and hence pointers of
<o:p></o:p></p>
<p class="MsoNormal">different AS can have the same Id. If it is intended, I am not sure that the early continue here, only based on the DependenceSetId, handled all cases)<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormalCxSpMiddle" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in;mso-add-space:auto">
// Only need to check pointers between two different dependency sets.<o:p></o:p></p>
<p class="MsoNormalCxSpMiddle" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in;mso-add-space:auto">
<b> </b>if (RtCheck.Pointers[i].DependencySetId ==<o:p></o:p></p>
<p class="MsoNormalCxSpMiddle" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in;mso-add-space:auto">
RtCheck.Pointers[j].DependencySetId)<o:p></o:p></p>
<p class="MsoNormalCxSpMiddle" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in;mso-add-space:auto">
continue;<o:p></o:p></p>
<p class="MsoNormalCxSpMiddle" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in;mso-add-space:auto">
// Only need to check pointers in the same alias set.<o:p></o:p></p>
<p class="MsoNormalCxSpMiddle" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in;mso-add-space:auto">
if (RtCheck.Pointers[i].AliasSetId != RtCheck.Pointers[j].AliasSetId)<o:p></o:p></p>
<p class="MsoNormalCxSpMiddle" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in;mso-add-space:auto">
continue;<o:p></o:p></p>
<p class="MsoNormalCxSpMiddle" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in;mso-add-space:auto">
<o:p></o:p></p>
<p class="MsoNormalCxSpMiddle" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in;mso-add-space:auto">
Value *PtrI = RtCheck.Pointers[i].PointerValue;<o:p></o:p></p>
<p class="MsoNormalCxSpMiddle" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in;mso-add-space:auto">
Value *PtrJ = RtCheck.Pointers[j].PointerValue;<o:p></o:p></p>
<p class="MsoNormalCxSpMiddle" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in;mso-add-space:auto">
<o:p></o:p></p>
<p class="MsoNormalCxSpMiddle" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in;mso-add-space:auto">
unsigned ASi = PtrI->getType()->getPointerAddressSpace();<o:p></o:p></p>
<p class="MsoNormalCxSpMiddle" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in;mso-add-space:auto">
unsigned ASj = PtrJ->getType()->getPointerAddressSpace();<o:p></o:p></p>
<p class="MsoNormalCxSpMiddle" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in;mso-add-space:auto">
if (ASi != ASj) {<o:p></o:p></p>
<p class="MsoNormalCxSpMiddle" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in;mso-add-space:auto">
LLVM_DEBUG(<o:p></o:p></p>
<p class="MsoNormalCxSpMiddle" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in;mso-add-space:auto">
dbgs() << "LAA: Runtime check would require comparison between"<o:p></o:p></p>
<p class="MsoNormalCxSpMiddle" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in;mso-add-space:auto">
" different address spaces\n");<o:p></o:p></p>
<p class="MsoNormalCxSpMiddle" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in;mso-add-space:auto">
return false;<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">CD<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<div>
<div style="border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0in 0in 0in">
<p class="MsoNormal"><b>From:</b> Stefanos Baziotis <stefanos.baziotis@gmail.com>
<br>
<b>Sent:</b> Sunday, July 26, 2020 6:09 PM<br>
<b>To:</b> Devadasan, Christudasan <Christudasan.Devadasan@amd.com><br>
<b>Cc:</b> LLVM Dev <llvm-dev@lists.llvm.org><br>
<b>Subject:</b> Re: [llvm-dev] [LAA] RtCheck on pointers of different address spaces.<o:p></o:p></p>
</div>
</div>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">[CAUTION: External Email] <o:p></o:p></p>
<div>
<div>
<p class="MsoNormal">Hi,<br>
<br>
There are a lot of things going on here, but given this:<br>
<br>
> The crash occurs with the pointers 1 & 4 which are from AS1 and AS2 respectively.<br>
<br>
and the trace, I'm not sure how that can happen. `groupChecks()` will only try to group pointers that<br>
are on the same alias set (because it will only try to group pointers that are in the same Eq class
<o:p></o:p></p>
<div>
<p class="MsoNormal">in DepCands, which if you see its construction in `processMemAccesses()`, won't put two pointers<br>
from different alias sets in the same Eq Class because _theoretically_, two such pointers can't<br>
share an underlying object).<br>
<br>
Do maybe have a simplified but complete IR ? Is that a possibility?<br>
<br>
Kind regards,<br>
Stefanos Baziotis<o:p></o:p></p>
</div>
</div>
<p class="MsoNormal"><o:p> </o:p></p>
<div>
<div>
<p class="MsoNormal">Στις Κυρ, 26 Ιουλ 2020 στις 1:06 μ.μ., ο/η Devadasan, Christudasan via llvm-dev <<a href="mailto:llvm-dev@lists.llvm.org" target="_blank">llvm-dev@lists.llvm.org</a>> έγραψε:<o:p></o:p></p>
</div>
<blockquote style="border:none;border-left:solid #CCCCCC 1.0pt;padding:0in 0in 0in 6.0pt;margin-left:4.8pt;margin-right:0in">
<div>
<div>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Hello,<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">I Have a question related to the RT check on pointers during Loop Access Analysis pass.<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">There is a testcase with loop code that consist of 4 different memory operations referring two global objects of different address spaces.
<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">One from global constant (address space 4, addr_size = 64) and the other from local, LDS (address space 3, addr_size= 32).<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">(Details of various address spaces available for AMDGPU backend:
<a href="https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Fllvm.org%2Fdocs%2FAMDGPUUsage.html%23address-spaces&data=02%7C01%7CChristudasan.Devadasan%40amd.com%7C4a42db7316004baa429c08d83160f7e7%7C3dd8961fe4884e608e11a82d994e183d%7C0%7C0%7C637313639833494292&sdata=r7fk%2FU%2FCZLt8RKZNc0lAco6wBJKKDj%2Br621r%2FaBOI6A%3D&reserved=0" target="_blank">
https://llvm.org/docs/AMDGPUUsage.html#address-spaces</a>)<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">With upstream compiler, the testcase fails with a crash (given at the end of the e-mail) in the opt while trying to generate the RT check for these pointers. Precisely, with two
pointers of different address spaces.<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">The operand type check fails while trying to insert a ‘AddExpr’ SCEV node as their effective type differs for these pointers (One with 32-bit and the other with 64-bit)<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><b>Question: Is this intended to try for the RtCheck on pointers from different address spaces?
</b><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> The comments given in the code snippet (below) hints they aren’t.<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Code snippet from LoopAccessAnalysis.cpp:<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">-----------------------------------------------------------------------------------------------------------------------<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
bool AccessAnalysis::canCheckPtrAtRT(...) {<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
----------<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
// If the pointers that we would use for the bounds comparison have different<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
// address spaces, assume the values aren't directly comparable, so we can't<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
// use them for the runtime check. We also have to assume they could<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
// overlap. In the future there should be metadata for whether address spaces<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
// are disjoint.<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
unsigned NumPointers = RtCheck.Pointers.size();<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
for (unsigned i = 0; i < NumPointers; ++i) {<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
for (unsigned j = i + 1; j < NumPointers; ++j) {<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
// Only need to check pointers between two different dependency sets.<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
if (RtCheck.Pointers[i].DependencySetId ==<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
RtCheck.Pointers[j].DependencySetId)<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
continue;<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
// Only need to check pointers in the same alias set.<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
if (RtCheck.Pointers[i].AliasSetId != RtCheck.Pointers[j].AliasSetId)<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
continue;<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
Value *PtrI = RtCheck.Pointers[i].PointerValue;<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
Value *PtrJ = RtCheck.Pointers[j].PointerValue;<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
unsigned ASi = PtrI->getType()->getPointerAddressSpace();<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
unsigned ASj = PtrJ->getType()->getPointerAddressSpace();<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
if (ASi != ASj) {<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
LLVM_DEBUG(<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
dbgs() << "LAA: Runtime check would require comparison between"<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
" different address spaces\n");<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
return false;<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
}<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
}<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">----------------------------------------------------------------------------------------------------<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">More details about the objects, the pointers and the memory operations:<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">----------------------------------------------------------------------------------------------------<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
%struct_var1 = type { <2 x float> }<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
%struct_var2 = type { %struct_var1 }<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
%class_var1 = type { i32, i32, i32, %struct_var2*, i32, i32, i32}<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
%class_var2 = type { %class_var1, i8, i8*, i32 }<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
Objects:<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
@Obj1 = external protected local_unnamed_addr addrspace(4) externally_initialized global %class_var2, align 8<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
@Obj2 = internal unnamed_addr addrspace(3) constant [4000 x float] undef, align 16<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
Pointers:<o:p></o:p></p>
<p style="margin-left:1.0in">1.<span style="font-size:7.0pt;font-family:"Times New Roman",serif">
</span>%struct_var1.cast = bitcast %struct_var1* %struct_var2.gep to i64* (write) // AS1<o:p></o:p></p>
<p style="margin-left:1.0in">2.<span style="font-size:7.0pt;font-family:"Times New Roman",serif">
</span>%struct_var2.cast = bitcast %struct_var2* %arrayidx74 to i64* (read-only) // AS1<o:p></o:p></p>
<p style="margin-left:1.0in">3.<span style="font-size:7.0pt;font-family:"Times New Roman",serif">
</span>%arrayidx1705 = getelementptr inbounds [4000 x float], [4000 x float] addrspace(3)* @Obj2, i32 0, i32 %add125 (read-only) // AS2<o:p></o:p></p>
<p style="margin-left:1.0in">4.<span style="font-size:7.0pt;font-family:"Times New Roman",serif">
</span>%arrayidx274 = getelementptr inbounds [4000 x float], [4000 x float] addrspace(3)* @Obj2, i32 0, i32 %arg1 (read-only) // AS2<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
While the pointers 1 & 2 belong to one Alias Set (AS1), pointers 3 & 4 belong to a different set (AS2). It is because, the Global Alias Analysis found there is no alias between these two sets of pointers.<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
The crash occurs with the pointers 1 & 4 which are from AS1 and AS2 respectively.
<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
The DependenceSetId will be reset to 1 before processing a new AS and the pointers in question, ended up having the same DependenceSetId (1), though they are from different AS.<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> ----------------------------------------------------------------------------------------------------------------------------------------------------------<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> The load/store (memory operations) using these pointers in the loop. (extracted only the relevant instructions):<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> ----------------------------------------------------------------------------------------------------------------------------------------------------------<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> define protected amdgpu_kernel void @test_func(i32 %arg1, i32 %arg2) {<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> entry:<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
<b>%arrayidx274 = getelementptr inbounds [4000 x float], [4000 x float] addrspace(3)* @Obj2, i32 0, i32 %arg1</b><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
<b> </b>---------<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
br i1 %cmp1, label %header, label %for.end<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
header:<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
% <b>struct_var2.ld</b> = load %struct_var2*, %struct_var2* addrspace(4)* getelementptr inbounds (%class_var2, %class_var2 addrspace(4)* @Obj1, i64 0, i32 0, i32 3), align 8<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
%struct_var2.gep = getelementptr inbounds %struct_var2, %struct_var2* %struct_var2.ld, i64 undef, i32 0<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
<b> %struct_var1.cast = bitcast %struct_var1* %struct_var2.gep to i64*</b><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
br label %for.body<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
for.body:<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
--------- <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
%arrayidx74 = getelementptr inbounds %struct_var2, %struct_var2* %struct_var2.ld, i64 %idxprom73<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
<b> %struct_var2.cast = bitcast %struct_var2* %arrayidx74 to i64*</b><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
<b> </b>%for.body.ld = load i64, i64* %<b>struct_var2.cast</b>, align 8<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
---------<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
br i1 %cmp2, label %if.then, label %if.end<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
if.then:<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
%rem = srem i32 1, %arg2<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
%add125 = add nuw nsw i32 %rem, 1<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
<b> %arrayidx1705 = getelementptr inbounds [4000 x float], [4000 x float] addrspace(3)* @Obj2, i32 0, i32 %add125</b><o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
%arrayidx1705.ld = load float, float addrspace(3)* %<b>arrayidx1705</b>, align 4<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
%arrayidx274.ld = load float, float addrspace(3)* %<b>arrayidx274</b>, align 4<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
---------<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
br label %if.end<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
if.end:<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
store i64 %for.body.ld, i64* %<b>struct_var1.cast</b>, align 8<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
---------<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
br i1 %cmp3, label %for.body, label %for.end<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
for.end:<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
br exit<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
exit:<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> }<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">----------------------------------------------------------------------------------------------------------------------------------------------------------<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">The actual crash and the back-trace:<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">----------------------------------------------------------------------------------------------------------------------------------------------------------<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
opt: $SRC/llvm-project/llvm/lib/Analysis/ScalarEvolution.cpp:2165: const llvm::SCEV *llvm::ScalarEvolution::getAddExpr(SmallVectorImpl<const llvm::SCEV *> &, SCEV::NoWrapFlags, unsigned int): Assertion `getEffectiveSCEVType(Ops[i]->getType()) == ETy && "SCEVAddExpr
operand types don't match!"' failed.<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
PLEASE submit a bug report to <a href="https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Fbugs.llvm.org%2F&data=02%7C01%7CChristudasan.Devadasan%40amd.com%7C4a42db7316004baa429c08d83160f7e7%7C3dd8961fe4884e608e11a82d994e183d%7C0%7C0%7C637313639833494292&sdata=L20o6evK45pVbZE4E8csnx6Oc2mBvNihZNNTh0qYMN8%3D&reserved=0" target="_blank">
https://bugs.llvm.org/</a> and include the crash backtrace.<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
Stack dump:<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
0. Program arguments: $Tools/bin/opt -O3 test.ll -o out.ll<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
llvm::ScalarEvolution::getAddExpr(llvm::SmallVectorImpl<llvm::SCEV const*>&, llvm::SCEV::NoWrapFlags, unsigned int) $SRC/llvm-project/llvm/lib/Analysis/ScalarEvolution.cpp:2164:5<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
llvm::ScalarEvolution::getAddExpr(llvm::SCEV const*, llvm::SCEV const*, llvm::SCEV::NoWrapFlags, unsigned int) $SRC/llvm-project/llvm/include/llvm/Analysis/ScalarEvolution.h:526:3<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
llvm::ScalarEvolution::getMinusSCEV(llvm::SCEV const*, llvm::SCEV const*, llvm::SCEV::NoWrapFlags, unsigned int) $SRC/llvm-project/llvm/lib/Analysis/ScalarEvolution.cpp:3833:3<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
getMinFromExprs(llvm::SCEV const*, llvm::SCEV const*, llvm::ScalarEvolution*) $SRC/llvm-project/llvm/lib/Analysis/LoopAccessAnalysis.cpp:275:15<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
llvm::RuntimeCheckingPtrGroup::addPointer(unsigned int) $SRC/llvm-project/llvm/lib/Analysis/LoopAccessAnalysis.cpp:292:15<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
llvm::RuntimePointerChecking::groupChecks(llvm::EquivalenceClasses<llvm::PointerIntPair<llvm::Value*, 1u, bool, llvm::PointerLikeTypeTraits<llvm::Value*>, llvm::PointerIntPairInfo<llvm::Value*, 1u, llvm::PointerLikeTypeTraits<llvm::Value*> > > >&, bool) $SRC/llvm-project/llvm/lib/Analysis/LoopAccessAnalysis.cpp:413:13<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
llvm::RuntimePointerChecking::generateChecks(llvm::EquivalenceClasses<llvm::PointerIntPair<llvm::Value*, 1u, bool, llvm::PointerLikeTypeTraits<llvm::Value*>, llvm::PointerIntPairInfo<llvm::Value*, 1u, llvm::PointerLikeTypeTraits<llvm::Value*> > > >&, bool)
$SRC/llvm-project/llvm/lib/Analysis/LoopAccessAnalysis.cpp:259:12<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
(anonymous namespace)::AccessAnalysis::canCheckPtrAtRT(llvm::RuntimePointerChecking&, llvm::ScalarEvolution*, llvm::Loop*, llvm::DenseMap<llvm::Value const*, llvm::Value*, llvm::DenseMapInfo<llvm::Value const*>, llvm::detail::DenseMapPair<llvm::Value const*,
llvm::Value*> > const&, bool) $SRC/llvm-project/llvm/lib/Analysis/LoopAccessAnalysis.cpp:830:3<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
llvm::LoopAccessInfo::analyzeLoop(llvm::AAResults*, llvm::LoopInfo*, llvm::TargetLibraryInfo const*, llvm::DominatorTree*) $SRC/llvm-project/llvm/lib/Analysis/LoopAccessAnalysis.cpp:2038:8<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
llvm::LoopAccessInfo::LoopAccessInfo(llvm::Loop*, llvm::ScalarEvolution*, llvm::TargetLibraryInfo const*, llvm::AAResults*, llvm::DominatorTree*, llvm::LoopInfo*) $SRC/llvm-project/llvm/lib/Analysis/LoopAccessAnalysis.cpp:2222:1<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
std::_MakeUniq<llvm::LoopAccessInfo>::__single_object std::make_unique<llvm::LoopAccessInfo, llvm::Loop*&, llvm::ScalarEvolution*&, llvm::TargetLibraryInfo const*&, llvm::AAResults*&, llvm::DominatorTree*&, llvm::LoopInfo*&>(llvm::Loop*&, llvm::ScalarEvolution*&,
llvm::TargetLibraryInfo const*&, llvm::AAResults*&, llvm::DominatorTree*&, llvm::LoopInfo*&) /usr/bin/../lib/gcc/x86_64-linux-gnu/7.5.0/../../../../include/c++/7.5.0/bits/unique_ptr.h:821:34<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
llvm::LoopAccessLegacyAnalysis::getInfo(llvm::Loop*) $SRC/llvm-project/llvm/lib/Analysis/LoopAccessAnalysis.cpp:2275:5<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
(anonymous namespace)::LoopLoadElimination::runOnFunction(llvm::Function&)::'lambda'(llvm::Loop&)::operator()(llvm::Loop&) const $SRC/llvm-project/llvm/lib/Transforms/Scalar/LoopLoadElimination.cpp:651:53<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
llvm::LoopAccessInfo const& llvm::function_ref<llvm::LoopAccessInfo const& (llvm::Loop&)>::callback_fn<(anonymous namespace)::LoopLoadElimination::runOnFunction(llvm::Function&)::'lambda'(llvm::Loop&)>(long, llvm::Loop&) $SRC/llvm-project/llvm/include/llvm/ADT/STLExtras.h:185:5<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
llvm::function_ref<llvm::LoopAccessInfo const& (llvm::Loop&)>::operator()(llvm::Loop&) const $SRC/llvm-project/llvm/include/llvm/ADT/STLExtras.h:203:5<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
eliminateLoadsAcrossLoops(llvm::Function&, llvm::LoopInfo&, llvm::DominatorTree&, llvm::BlockFrequencyInfo*, llvm::ProfileSummaryInfo*, llvm::function_ref<llvm::LoopAccessInfo const& (llvm::Loop&)>) $SRC/llvm-project/llvm/lib/Transforms/Scalar/LoopLoadElimination.cpp:618:53<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
(anonymous namespace)::LoopLoadElimination::runOnFunction(llvm::Function&) $SRC/llvm-project/llvm/lib/Transforms/Scalar/LoopLoadElimination.cpp:649:5<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
llvm::FPPassManager::runOnFunction(llvm::Function&) $SRC/llvm-project/llvm/lib/IR/LegacyPassManager.cpp:1587:23<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
llvm::FPPassManager::runOnModule(llvm::Module&) $SRC/llvm-project/llvm/lib/IR/LegacyPassManager.cpp:1629:16<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
(anonymous namespace)::MPPassManager::runOnModule(llvm::Module&) $SRC/llvm-project/llvm/lib/IR/LegacyPassManager.cpp:1698:23<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
llvm::legacy::PassManagerImpl::run(llvm::Module&) $SRC/llvm-project/llvm/lib/IR/LegacyPassManager.cpp:614:16<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
llvm::legacy::PassManager::run(llvm::Module&) $SRC/llvm-project/llvm/lib/IR/LegacyPassManager.cpp:1824:3<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
main $SRC/llvm-project/llvm/tools/opt/opt.cpp:955:3<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
__libc_start_main /build/glibc-2ORdQG/glibc-2.27/csu/../csu/libc-start.c:344:0<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
_start ($Tools/bin/opt+0xc98b6a)<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;margin-left:.5in">
Aborted (core dumped)<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">-----------------------------------------------------------------------------------------------------------------------------------------------------------------<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Regards,<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">CD<o:p></o:p></p>
</div>
</div>
<p class="MsoNormal">_______________________________________________<br>
LLVM Developers mailing list<br>
<a href="mailto:llvm-dev@lists.llvm.org" target="_blank">llvm-dev@lists.llvm.org</a><br>
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</blockquote>
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