Yonghong Song f6a86e448a BPF: avoid NE/EQ loop exit condition ... Kuniyuki Iwashima reported in [1] that llvm compiler may convert a loop exit condition with "i < bound" to "i != bound", where "i" is the loop index variable and "bound" is the upper bound. In case that "bound" is not a constant, verifier will always have "i != bound" true, which will cause verifier failure since to verifier this is an infinite loop. The fix is to avoid transforming "i < bound" to "i != bound". In llvm, the transformation is done by IndVarSimplify pass. The compiler checks loop condition cost (i = i + 1) and if the cost is lower, it may transform "i < bound" to "i != bound". This patch implemented getArithmeticInstrCost() in BPF TargetTransformInfo class to return a higher cost for such an operation, which will prevent the transformation for the test case added in this patch. [1] https://lore.kernel.org/netdev/1994df05-8f01-371f-3c3b-d33d7836878c@fb.com/ Differential Revision: https://reviews.llvm.org/D107483 (cherry picked from commit e52946b9ababcbf8e6f40b1b15900ae2e795a1c6)		2021-08-06 12:45:53 -07:00
..
AsmParser
Disassembler	[BPF] support atomic instructions	2020-12-03 07:38:00 -08:00
MCTargetDesc	BPF: Add more relocation kinds	2021-05-25 08:19:13 -07:00
TargetInfo
BPF.h	[BPF][NewPM] Port bpf-adjust-opt to NPM and add it to pipeline	2020-11-26 10:11:26 -08:00
BPF.td
BPFAbstractMemberAccess.cpp	[BPF] Use elementtype attribute for preserve.array/struct.index intrinsics	2021-07-17 11:09:18 +02:00
BPFAdjustOpt.cpp	Update BPFAdjustOpt.cpp to accept select form of or as well	2021-02-20 18:29:58 +09:00
BPFAsmPrinter.cpp
BPFCallingConv.td
BPFCheckAndAdjustIR.cpp
BPFCORE.h
BPFFrameLowering.cpp
BPFFrameLowering.h
BPFInstrFormats.td	[BPF] support atomic instructions	2020-12-03 07:38:00 -08:00
BPFInstrInfo.cpp
BPFInstrInfo.h
BPFInstrInfo.td	[BPF] support atomic instructions	2020-12-03 07:38:00 -08:00
BPFISelDAGToDAG.cpp	BPFISelDAGToDAG.cpp - don't dereference a dyn_cast<> result. NFCI.	2021-06-06 13:24:29 +01:00
BPFISelLowering.cpp	[BPF] add support for 32 bit registers in inline asm	2021-05-16 11:01:47 -07:00
BPFISelLowering.h	[BPF] add support for 32 bit registers in inline asm	2021-05-16 11:01:47 -07:00
BPFMCInstLower.cpp
BPFMCInstLower.h
BPFMIChecking.cpp	[BPF] support atomic instructions	2020-12-03 07:38:00 -08:00
BPFMIPeephole.cpp	BPF: Fix a bug in peephole TRUNC elimination optimization	2021-03-02 13:03:42 -08:00
BPFMISimplifyPatchable.cpp
BPFPreserveDIType.cpp	BPF: permit type modifiers for __builtin_btf_type_id() relocation	2021-03-04 16:27:23 -08:00
BPFRegisterInfo.cpp
BPFRegisterInfo.h
BPFRegisterInfo.td
BPFSelectionDAGInfo.cpp
BPFSelectionDAGInfo.h
BPFSubtarget.cpp
BPFSubtarget.h
BPFTargetMachine.cpp	[NewPM] Hide pass manager debug logging behind -debug-pass-manager-verbose	2021-05-07 21:51:47 -07:00
BPFTargetMachine.h	[NewPM] Hide pass manager debug logging behind -debug-pass-manager-verbose	2021-05-07 21:51:47 -07:00
BPFTargetTransformInfo.h	BPF: avoid NE/EQ loop exit condition	2021-08-06 12:45:53 -07:00
BTF.def	[BPF] Add support for floats and doubles	2021-03-05 15:10:11 +01:00
BTF.h
BTFDebug.cpp	BPF: generate BTF info for LD_imm64 loaded function pointer	2021-04-26 17:23:36 -07:00
BTFDebug.h	BPF: generate BTF info for LD_imm64 loaded function pointer	2021-04-26 17:23:36 -07:00
CMakeLists.txt	BPF: Add LLVMTransformUtils in CMakefile LINK_COMPONENTS	2021-02-25 15:43:25 -08:00