Propagate Addrspaces: fix lift of memset

[wsmoses]

No description provided.

[wsmoses]

currently this results in an inserted instruction (bitcast) without a parent -- and is used in a memset:

Thread 2 received signal SIGSEGV, Segmentation fault.
[Switching to Thread 1354226.1354226]
<signal handler called>
(rr) bt
#0  <signal handler called>
#1  llvm::Instruction::insertBefore (this=0x644400c31e10, InsertPos=0x0)
    at /home/wmoses/git/julia11/deps/srccache/llvm-julia-16.0.6-3/llvm/include/llvm/IR/Instruction.h:91
#2  0x00007adc233fd6d7 in propagateJuliaAddrspaces (F=...) at /home/wmoses/git/julia11/src/llvm-propagate-addrspaces.cpp:290
#3  0x00007adc233fd7f4 in PropagateJuliaAddrspacesPass::run (this=0x644402a23778, F=..., AM=...)
    at /home/wmoses/git/julia11/src/llvm-propagate-addrspaces.cpp:300
#4  0x00007adc2348b136 in llvm::detail::PassModel<llvm::Function, PropagateJuliaAddrspacesPass, llvm::PreservedAnalyses, llvm::AnalysisManager<llvm::Function>>::run(llvm::Function&, llvm::AnalysisManager<llvm::Function>&) (this=0x644402a23770, IR=..., AM=...)
    at /home/wmoses/git/julia11/usr/include/llvm/IR/PassManagerInternal.h:89
#5  0x00007adc1fe12405 in llvm::PassManager<llvm::Function, llvm::AnalysisManager<llvm::Function>>::run(llvm::Function&, llvm::AnalysisManager<llvm::Function>&) (AM=..., IR=..., this=<optimized out>) at /home/wmoses/git/julia11/deps/srccache/llvm-julia-16.0.6-3/llvm/include/llvm/IR/PassManager.h:517
#6  llvm::detail::PassModel<llvm::Function, llvm::PassManager<llvm::Function, llvm::AnalysisManager<llvm::Function>>, llvm::PreservedAnalyses, llvm::AnalysisManager<llvm::Function>>::run(llvm::Function&, llvm::AnalysisManager<llvm::Function>&) (this=<optimized out>, IR=..., AM=...)
    at /home/wmoses/git/julia11/deps/srccache/llvm-julia-16.0.6-3/llvm/include/llvm/IR/PassManagerInternal.h:89
#7  0x00007adc1da89901 in llvm::ModuleToFunctionPassAdaptor::run (this=<optimized out>, M=..., AM=...)
    at /home/wmoses/git/julia11/deps/srccache/llvm-julia-16.0.6-3/llvm/lib/IR/PassManager.cpp:124
#8  0x00007adc1fe03515 in llvm::detail::PassModel<llvm::Module, llvm::ModuleToFunctionPassAdaptor, llvm::PreservedAnalyses, llvm::AnalysisManager<llvm::Module>>::run(llvm::Module&, llvm::AnalysisManager<llvm::Module>&) (this=<optimized out>, IR=..., AM=...)
    at /home/wmoses/git/julia11/deps/srccache/llvm-julia-16.0.6-3/llvm/include/llvm/IR/PassManagerInternal.h:89
#9  0x00007adc1676b1ca in llvm::PassManager<llvm::Module, llvm::AnalysisManager<llvm::Module>>::run(llvm::Module&, llvm::AnalysisManager<llvm::Module>&) (
    AM=..., IR=..., this=0x7ffed0db39b0) at /opt/x86_64-linux-gnu/x86_64-linux-gnu/sys-root/usr/local/include/llvm/IR/PassManager.h:517
#10 runJuliaPasses (Mod=0x644401cb21d0, Fun=<optimized out>, Passes=<optimized out>, Machine=<optimized out>, PassOpts=<optimized out>, 
    PassExts=<optimized out>) at /workspace/srcdir/LLVM.jl/deps/LLVMExtra/lib/NewPM.cpp:217
#11 0x00007adbf1bb11d1 in julia_LLVMRunJuliaPasses_18057 (M=..., Passes=<error reading variable: Cannot access memory at address 0x0>, TM=<optimized out>, 
    Options=135085088173584, Extensions=110243209596432) at /home/wmoses/.julia/packages/LLVM/UFrs4/lib/16/libLLVM_extra.jl:397
#12 0x00007adbf1ac4547 in macro expansion () at /home/wmoses/.julia/packages/LLVM/UFrs4/src/executionengine/utils.jl:25
#13 julia_run!_17968 (pb=..., target=..., tm=...) at /home/wmoses/.julia/packages/LLVM/UFrs4/src/newpm.jl:291
#14 0x00007adbe956d89b in run! () at /home/wmoses/.julia/packages/LLVM/UFrs4/src/newpm.jl:252
#15 macro expansion () at /mnt3/wmoses/git/Enzyme.jl/src/compiler/optimize.jl:111
#16 macro expansion () at /home/wmoses/.julia/packages/LLVM/UFrs4/src/base.jl:97
#17 julia_prop_julia_addr_29938 (mod=...) at /mnt3/wmoses/git/Enzyme.jl/src/compiler/optimize.jl:105
#18 0x00007adbe943d03f in jfptr_prop_julia_addr_29939 () from /home/wmoses/.julia/compiled/v1.11/Enzyme/G1p5n_AGSw1.so
#19 0x00007adc24454141 in _jl_invoke (F=0x7adbe9918b60 <jl_system_image_data+1787296>, args=0x7ffed0db5168, nargs=1, 
    mfunc=0x7adbe9e0b6c0 <jl_system_image_data+6975744>, world=26770) at /home/wmoses/git/julia11/src/gf.c:2929
#20 0x00007adc24454ca9 in ijl_apply_generic (F=0x7adbe9918b60 <jl_system_image_data+1787296>, args=0x7ffed0db5168, nargs=1)
    at /home/wmoses/git/julia11/src/gf.c:3125
#21 0x00007adc241ced9a in julia_module_pass_callback_12823 (ptr=110243250643408, data=<optimized out>)
    at /home/wmoses/.julia/packages/LLVM/UFrs4/src/pass.jl:19
#22 0x00007adc241cee61 in jfptr_module_pass_callback_12824 ()
#23 0x00007adc24454141 in _jl_invoke (F=0x7adbfc01b270 <jl_system_image_data+4149808>, args=0x7ffed0db52e0, nargs=2, mfunc=0x7adc19c9e310, world=26770)
    at /home/wmoses/git/julia11/src/gf.c:2929
#24 0x00007adc24454ca9 in ijl_apply_generic (F=0x7adbfc01b270 <jl_system_image_data+4149808>, args=0x7ffed0db52e0, nargs=2)
    at /home/wmoses/git/julia11/src/gf.c:3125
#25 0x00007adbe95f01bf in jlcapi_module_pass_callback_30225 () from /home/wmoses/.julia/compiled/v1.11/Enzyme/G1p5n_AGSw1.so
#26 0x00007adc1675c6a1 in (anonymous namespace)::JuliaModulePass::runOnModule (this=<optimized out>, M=...)
    at /workspace/srcdir/LLVM.jl/deps/LLVMExtra/lib/Core.cpp:195
#27 0x00007adc1da3febe in (anonymous namespace)::MPPassManager::runOnModule (M=..., this=<optimized out>)
    at /home/wmoses/git/julia11/deps/srccache/llvm-julia-16.0.6-3/llvm/lib/IR/LegacyPassManager.cpp:1545
#28 llvm::legacy::PassManagerImpl::run (this=0x644401c6e0d0, M=...)
    at /home/wmoses/git/julia11/deps/srccache/llvm-julia-16.0.6-3/llvm/lib/IR/LegacyPassManager.cpp:535
#29 0x00007adc1d95dd62 in LLVMRunPassManager (PM=<optimized out>, M=<optimized out>)
--Type <RET> for more, q to quit, c to continue without paging--q
Quit
(rr) b propagateJuliaAddrspaces
Breakpoint 1 at 0x7adc233fd63a: file /home/wmoses/git/julia11/src/llvm-propagate-addrspaces.cpp, line 287.
(rr) rc
Continuing.

instruction was created here

(rr) finish
Run till exit from #0  0x00007adc233fd06b in PropagateJuliaAddrspacesVisitor::LiftPointer (this=0x7ffed0db3520, M=0x644401cb21d0, V=0x6444000c3f80, 
    InsertPt=0x0) at /home/wmoses/git/julia11/src/llvm-propagate-addrspaces.cpp:216
0x00007adc233fd2f7 in PropagateJuliaAddrspacesVisitor::visitMemSetInst (this=0x7ffed0db3520, MI=...)
    at /home/wmoses/git/julia11/src/llvm-propagate-addrspaces.cpp:250
250	    Value *Replacement = LiftPointer(MI.getModule(), MI.getRawDest());
Value returned is $11 = (llvm::Value *) 0x644400c31e10
(rr) n
251	    if (!Replacement)
(rr) p Replacement->dump()
  <badref> = bitcast i64* <badref> to i8*
$12 = void
(rr) b LiftPointer
Breakpoint 3 at 0x7adc233fc660: file /home/wmoses/git/julia11/src/llvm-propagate-addrspaces.cpp, line 83.
(rr) rc
Continuing.

Thread 2 hit Hardware watchpoint 2: *((llvm::BasicBlock **) 0x644400c31e38)

Old value = (llvm::BasicBlock *) 0x0
New value = (llvm::BasicBlock *) 0x7adc2314ccec <(anonymous namespace)::BreakCriticalEdges::ID>
llvm::Instruction::Instruction (this=0x644400c31e10, ty=<optimized out>, it=<optimized out>, Ops=<optimized out>, NumOps=<optimized out>, InsertBefore=0x0)
    at /home/wmoses/git/julia11/deps/srccache/llvm-julia-16.0.6-3/llvm/lib/IR/Instruction.cpp:26
26	  : User(ty, Value::InstructionVal + it, Ops, NumOps), Parent(nullptr) {
(rr) up
#1  0x00007adc1da0e765 in llvm::UnaryInstruction::UnaryInstruction (IB=<optimized out>, V=<optimized out>, iType=49, Ty=<optimized out>, 
    this=0x644400c31e10) at /home/wmoses/git/julia11/deps/srccache/llvm-julia-16.0.6-3/llvm/include/llvm/IR/OperandTraits.h:31
31	  static Use *op_begin(SubClass* U) {
(rr) 
#2  llvm::CastInst::CastInst (InsertBefore=<optimized out>, NameStr=..., S=<optimized out>, iType=49, Ty=<optimized out>, this=0x644400c31e10)
    at /home/wmoses/git/julia11/deps/srccache/llvm-julia-16.0.6-3/llvm/include/llvm/IR/InstrTypes.h:433
433	    : UnaryInstruction(Ty, iType, S, InsertBefore) {
(rr) 
#3  llvm::BitCastInst::BitCastInst (this=0x644400c31e10, S=0x6444023f23a0, Ty=0x6443fa3b7b80, Name=..., InsertBefore=<optimized out>)
    at /home/wmoses/git/julia11/deps/srccache/llvm-julia-16.0.6-3/llvm/lib/IR/Instructions.cpp:3971
3971	) : CastInst(Ty, BitCast, S, Name, InsertBefore) {
(rr) 
#4  0x00007adc233fc5cc in operator() (__closure=0x7ffed0db3230, CurrentV=0x6444023f23a0, InsertPt=0x0)
    at /home/wmoses/git/julia11/src/llvm-propagate-addrspaces.cpp:190
190	            auto *BCI = new BitCastInst(CurrentV, TargetType);
(rr) 
#5  0x00007adc233fd06b in PropagateJuliaAddrspacesVisitor::LiftPointer (this=0x7ffed0db3520, M=0x644401cb21d0, V=0x6444000c3f80, InsertPt=0x0)
    at /home/wmoses/git/julia11/src/llvm-propagate-addrspaces.cpp:216
216	    return CollapseCastsAndLift(V, InsertPt);
(rr) l
211	        } else {
212	            assert(false && "Shouldn't have reached here");
213	        }
214	    }
215	
216	    return CollapseCastsAndLift(V, InsertPt);
217	}
218	
219	void PropagateJuliaAddrspacesVisitor::visitMemop(Instruction &I, Type *T, unsigned OpIndex) {
220	    Value *Original = I.getOperand(OpIndex);
(rr) p InsertPt
$13 = (llvm::Instruction *) 0x0
(rr) up
#6  0x00007adc233fd2f7 in PropagateJuliaAddrspacesVisitor::visitMemSetInst (this=0x7ffed0db3520, MI=...)
    at /home/wmoses/git/julia11/src/llvm-propagate-addrspaces.cpp:250
250	    Value *Replacement = LiftPointer(MI.getModule(), MI.getRawDest());
(rr) down
#5  0x00007adc233fd06b in PropagateJuliaAddrspacesVisitor::LiftPointer (this=0x7ffed0db3520, M=0x644401cb21d0, V=0x6444000c3f80, InsertPt=0x0)
    at /home/wmoses/git/julia11/src/llvm-propagate-addrspaces.cpp:216
216	    return CollapseCastsAndLift(V, InsertPt);
(rr) up
#6  0x00007adc233fd2f7 in PropagateJuliaAddrspacesVisitor::visitMemSetInst (this=0x7ffed0db3520, MI=...)
    at /home/wmoses/git/julia11/src/llvm-propagate-addrspaces.cpp:250
250	    Value *Replacement = LiftPointer(MI.getModule(), MI.getRawDest());
(rr) l
245	
246	void PropagateJuliaAddrspacesVisitor::visitMemSetInst(MemSetInst &MI) {
247	    unsigned AS = MI.getDestAddressSpace();
248	    if (!isSpecialAS(AS))
249	        return;
250	    Value *Replacement = LiftPointer(MI.getModule(), MI.getRawDest());
251	    if (!Replacement)
252	        return;
253	    Function *TheFn = Intrinsic::getDeclaration(MI.getModule(), Intrinsic::memset,
254	        {Replacement->getType(), MI.getOperand(1)->getType()});
(rr) l
255	    MI.setCalledFunction(TheFn);
256	    MI.setArgOperand(0, Replacement);
257	}
258	
259	void PropagateJuliaAddrspacesVisitor::visitMemTransferInst(MemTransferInst &MTI) {
260	    unsigned DestAS = MTI.getDestAddressSpace();
261	    unsigned SrcAS = MTI.getSourceAddressSpace();
262	    if (!isSpecialAS(DestAS) && !isSpecialAS(SrcAS))
263	        return;
264	    Value *Dest = MTI.getRawDest();

[vchuravy]

Can you audit other uses of LiftPointer and perhaps we could remove the default Nullpointer argument and always require an insertion point?

[gbaraldi]

It also could do with a test