LLVM crashes when returning large values by-val an building for sparc64

[nagisa]

Bugzilla Link	48699
Version	trunk
OS	All

Extended Description

Code

define i2048 @​test() unnamed_addr {
start:
  ret i2048 0
}

built with llc -mtriple=sparc64 will fail with the following assertion:

PLEASE submit a bug report to https://bugs.llvm.org/ and include the crash backtrace.
Stack dump:
0. Program arguments: /opt/compiler-explorer/clang-trunk/bin/llc -o ./output.s -mtriple=sparc64

1. Running pass 'Function Pass Manager' on module ''.
2. Running pass 'Remove dead machine instructions' on function '@test'

#​4 0x000055c9d8d52d74 (anonymous namespace)::DeadMachineInstructionElim::eliminateDeadMI(llvm::MachineFunction&) (/opt/compiler-explorer/clang-trunk/bin/llc+0x1bc1d74) #​5 0x000055c9d8d53313 (anonymous namespace)::DeadMachineInstructionElim::runOnMachineFunction(llvm::MachineFunction&) (/opt/compiler-explorer/clang-trunk/bin/llc+0x1bc2313) #​6 0x000055c9d8e5e2c8 llvm::MachineFunctionPass::runOnFunction(llvm::Function&) (/opt/compiler-explorer/clang-trunk/bin/llc+0x1ccd2c8) #​7 0x000055c9d92355e7 llvm::FPPassManager::runOnFunction(llvm::Function&) (/opt/compiler-explorer/clang-trunk/bin/llc+0x20a45e7) #​8 0x000055c9d9235d01 llvm::FPPassManager::runOnModule(llvm::Module&) (/opt/compiler-explorer/clang-trunk/bin/llc+0x20a4d01) #​9 0x000055c9d923507f llvm::legacy::PassManagerImpl::run(llvm::Module&) (/opt/compiler-explorer/clang-trunk/bin/llc+0x20a407f) #​10 0x000055c9d79aea4a compileModule(char**, llvm::LLVMContext&) (/opt/compiler-explorer/clang-trunk/bin/llc+0x81da4a) #​11 0x000055c9d78ee267 main (/opt/compiler-explorer/clang-trunk/bin/llc+0x75d267)

[nagisa]

Notably this failure does not occur when some other targets (I tried x86_64 & aarch64) are specified.

[koachan]

This should be fixed by d3fcbee

https://godbolt.org/z/Yafvzd6ao