[PATCH] D89170: [AMDGPU] Select flat scratch instructions where available

[Stanislav Mekhanoshin via Phabricator via llvm-commits]

rampitec added inline comments.


================
Comment at: llvm/lib/Target/AMDGPU/SIRegisterInfo.cpp:1416-1421
+        } else if (ST.hasFlatScratchSTMode()) {
+          unsigned Opc = MI->getOpcode();
+          unsigned NewOpc = AMDGPU::getFlatScratchInstSTfromSS(Opc);
+          MI->RemoveOperand(
+              AMDGPU::getNamedOperandIdx(Opc, AMDGPU::OpName::saddr));
+          MI->setDesc(TII->get(NewOpc));
----------------
Flakebi wrote:
> I get a failing assert here with `NewOpc = 4294967295`:
> ```
> llvm/include/llvm/MC/MCInstrInfo.h:63: const llvm::MCInstrDesc &llvm::MCInstrInfo::get(unsigned int) const: Assertion `Opcode < NumOpcodes && "Invalid opcode!"' failed.
> PLEASE submit a bug report to https://bugs.llvm.org/ and include the crash backtrace.
> Stack dump:
> 0.      Program arguments: compiler/llpc/amdllpc -gfxip=10.1 -amdgpu-enable-flat-scratch /pipelines/PipelineVsFs_0x1BEFB7D1A235B4F6.pipe -verify-machineinstrs
> 1.      Running pass 'CallGraph Pass Manager' on module 'lgcPipeline'.
> 2.      Running pass 'Prologue/Epilogue Insertion & Frame Finalization' on function '@_amdgpu_ps_main'
>  #0 0x00000000023f0db1 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) /llvm/lib/Support/Unix/Signals.inc:563:13
>  #1 0x00000000023ef060 llvm::sys::RunSignalHandlers() /llvm/lib/Support/Signals.cpp:72:18
>  #2 0x00000000023f1152 SignalHandler(int) /llvm/lib/Support/Unix/Signals.inc:0:3
>  #3 0x00007fadd6ebfee0 __restore_rt (/glibc-2.31/lib/libpthread.so.0+0x12ee0)
>  #4 0x00007fadd6d0c08a raise (/glibc-2.31/lib/libc.so.6+0x3808a)
>  #5 0x00007fadd6cf6528 abort (/glibc-2.31/lib/libc.so.6+0x22528)
>  #6 0x00007fadd6cf640f _nl_load_domain.cold.0 (/glibc-2.31/lib/libc.so.6+0x2240f)
>  #7 0x00007fadd6d04a02 (/glibc-2.31/lib/libc.so.6+0x30a02)
>  #8 0x0000000001a03170 llvm::SIRegisterInfo::eliminateFrameIndex(llvm::MachineInstrBundleIterator<llvm::MachineInstr, false>, int, unsigned int, llvm::RegScavenger*) const /llvm/lib/Target/AMDGPU/SIRegisterInfo.cpp:1465:11
>  #9 0x000000000214e0f3 (anonymous namespace)::PEI::replaceFrameIndices(llvm::MachineBasicBlock*, llvm::MachineFunction&, int&) /llvm/lib/CodeGen/PrologEpilogInserter.cpp:0:11
> #10 0x000000000214caef llvm::MachineBasicBlock::getNumber() const /llvm/include/llvm/CodeGen/MachineBasicBlock.h:904:34
> #11 0x000000000214caef (anonymous namespace)::PEI::replaceFrameIndices(llvm::MachineFunction&) /llvm/lib/CodeGen/PrologEpilogInserter.cpp:1161:17
> #12 0x000000000214caef (anonymous namespace)::PEI::runOnMachineFunction(llvm::MachineFunction&) /llvm/lib/CodeGen/PrologEpilogInserter.cpp:269:3
> #13 0x0000000002031e7e llvm::MachineFunctionPass::runOnFunction(llvm::Function&) /llvm/lib/CodeGen/MachineFunctionPass.cpp:0:13
> #14 0x0000000003136a85 llvm::FPPassManager::runOnFunction(llvm::Function&) /llvm/lib/IR/LegacyPassManager.cpp:1519:27
> #15 0x0000000001c76b38 (anonymous namespace)::CGPassManager::RunPassOnSCC(llvm::Pass*, llvm::CallGraphSCC&, llvm::CallGraph&, bool&, bool&) /llvm/lib/Analysis/CallGraphSCCPass.cpp:178:25
> #16 0x0000000001c76b38 (anonymous namespace)::CGPassManager::RunAllPassesOnSCC(llvm::CallGraphSCC&, llvm::CallGraph&, bool&) /llvm/lib/Analysis/CallGraphSCCPass.cpp:476:9
> #17 0x0000000001c76b38 (anonymous namespace)::CGPassManager::runOnModule(llvm::Module&) /llvm/lib/Analysis/CallGraphSCCPass.cpp:541:18
> #18 0x0000000003137149 (anonymous namespace)::MPPassManager::runOnModule(llvm::Module&) /llvm/lib/IR/LegacyPassManager.cpp:0:27
> #19 0x0000000003137149 llvm::legacy::PassManagerImpl::run(llvm::Module&) /llvm/lib/IR/LegacyPassManager.cpp:615:44
> …
> ```
I cannot reproduce this. Take in mind that D89424 is not updated to use ST mode yet, so they do not work together yet.


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  https://reviews.llvm.org/D89170/new/

https://reviews.llvm.org/D89170