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llvm-project/llvm/test/CodeGen/BPF/atomics.ll

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[bpf] rename triple names bpf_be -> bpfeb llvm-svn: 239162
2015-06-06 00:11:14 +08:00
; RUN: llc < %s -march=bpfel -verify-machineinstrs -show-mc-encoding | FileCheck %s
[BPF] support atomic instructions Implement fetch_<op>/fetch_and_<op>/exchange/compare-and-exchange instructions for BPF. Specially, the following gcc intrinsics are implemented. __sync_fetch_and_add (32, 64) __sync_fetch_and_sub (32, 64) __sync_fetch_and_and (32, 64) __sync_fetch_and_or (32, 64) __sync_fetch_and_xor (32, 64) __sync_lock_test_and_set (32, 64) __sync_val_compare_and_swap (32, 64) For __sync_fetch_and_sub, internally, it is implemented as a negation followed by __sync_fetch_and_add. For __sync_lock_test_and_set, despite its name, it actually does an atomic exchange and return the old content. https://gcc.gnu.org/onlinedocs/gcc-4.1.1/gcc/Atomic-Builtins.html For intrinsics like __sync_{add,sub}_and_fetch and __sync_bool_compare_and_swap, the compiler is able to generate codes using __sync_fetch_and_{add,sub} and __sync_val_compare_and_swap. Similar to xadd, atomic xadd, xor and xxor (atomic_<op>) instructions are added for atomic operations which do not have return values. LLVM will check the return value for __sync_fetch_and_{add,and,or,xor}. If the return value is used, instructions atomic_fetch_<op> will be used. Otherwise, atomic_<op> instructions will be used. All new instructions only support 64bit and 32bit with alu32 mode. old xadd instruction still supports 32bit without alu32 mode. For encoding, please take a look at test atomics_2.ll. Differential Revision: https://reviews.llvm.org/D72184
2020-01-04 04:06:08 +08:00
; RUN: llc < %s -march=bpfel -verify-machineinstrs -show-mc-encoding -mcpu=v3 | FileCheck --check-prefix=CHECK-V3 %s
BPF backend Summary: V8->V9: - cleanup tests V7->V8: - addressed feedback from David: - switched to range-based 'for' loops - fixed formatting of tests V6->V7: - rebased and adjusted AsmPrinter args - CamelCased .td, fixed formatting, cleaned up names, removed unused patterns - diffstat: 3 files changed, 203 insertions(+), 227 deletions(-) V5->V6: - addressed feedback from Chandler: - reinstated full verbose standard banner in all files - fixed variables that were not in CamelCase - fixed names of #ifdef in header files - removed redundant braces in if/else chains with single statements - fixed comments - removed trailing empty line - dropped debug annotations from tests - diffstat of these changes: 46 files changed, 456 insertions(+), 469 deletions(-) V4->V5: - fix setLoadExtAction() interface - clang-formated all where it made sense V3->V4: - added CODE_OWNERS entry for BPF backend V2->V3: - fix metadata in tests V1->V2: - addressed feedback from Tom and Matt - removed top level change to configure (now everything via 'experimental-backend') - reworked error reporting via DiagnosticInfo (similar to R600) - added few more tests - added cmake build - added Triple::bpf - tested on linux and darwin V1 cover letter: --------------------- recently linux gained "universal in-kernel virtual machine" which is called eBPF or extended BPF. The name comes from "Berkeley Packet Filter", since new instruction set is based on it. This patch adds a new backend that emits extended BPF instruction set. The concept and development are covered by the following articles: http://lwn.net/Articles/599755/ http://lwn.net/Articles/575531/ http://lwn.net/Articles/603983/ http://lwn.net/Articles/606089/ http://lwn.net/Articles/612878/ One of use cases: dtrace/systemtap alternative. bpf syscall manpage: https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=b4fc1a460f3017e958e6a8ea560ea0afd91bf6fe instruction set description and differences vs classic BPF: http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/tree/Documentation/networking/filter.txt Short summary of instruction set: - 64-bit registers R0 - return value from in-kernel function, and exit value for BPF program R1 - R5 - arguments from BPF program to in-kernel function R6 - R9 - callee saved registers that in-kernel function will preserve R10 - read-only frame pointer to access stack - two-operand instructions like +, -, *, mov, load/store - implicit prologue/epilogue (invisible stack pointer) - no floating point, no simd Short history of extended BPF in kernel: interpreter in 3.15, x64 JIT in 3.16, arm64 JIT, verifier, bpf syscall in 3.18, more to come in the future. It's a very small and simple backend. There is no support for global variables, arbitrary function calls, floating point, varargs, exceptions, indirect jumps, arbitrary pointer arithmetic, alloca, etc. From C front-end point of view it's very restricted. It's done on purpose, since kernel rejects all programs that it cannot prove safe. It rejects programs with loops and with memory accesses via arbitrary pointers. When kernel accepts the program it is guaranteed that program will terminate and will not crash the kernel. This patch implements all 'must have' bits. There are several things on TODO list, so this is not the end of development. Most of the code is a boiler plate code, copy-pasted from other backends. Only odd things are lack or < and <= instructions, specialized load_byte intrinsics and 'compare and goto' as single instruction. Current instruction set is fixed, but more instructions can be added in the future. Signed-off-by: Alexei Starovoitov <alexei.starovoitov@gmail.com> Subscribers: majnemer, chandlerc, echristo, joerg, pete, rengolin, kristof.beyls, arsenm, t.p.northover, tstellarAMD, aemerson, llvm-commits Differential Revision: http://reviews.llvm.org/D6494 llvm-svn: 227008
2015-01-25 01:51:26 +08:00
; CHECK-LABEL: test_load_add_32
[bpf] add BPF disassembler add BPF disassembler, so tools like llvm-objdump can be used: $ llvm-objdump -d -no-show-raw-insn ./sockex1_kern.o ./sockex1_kern.o: file format ELF64-BPF Disassembly of section socket1: bpf_prog1: 0: r6 = r1 8: r0 = *(u8 *)skb[23] 10: *(u32 *)(r10 - 4) = r0 18: r1 = *(u32 *)(r6 + 4) 20: if r1 != 4 goto 8 28: r2 = r10 30: r2 += -4 ld_imm64 (the only 16-byte insn) and special ld_abs/ld_ind instructions had to be treated in a special way. The decoders for the rest of the insns are automatically generated. Add tests to cover new functionality. Signed-off-by: Alexei Starovoitov <ast@kernel.org> llvm-svn: 287477
2016-11-20 10:25:00 +08:00
; CHECK: lock *(u32 *)(r1 + 0) += r2
; CHECK: encoding: [0xc3,0x21
[BPF] support atomic instructions Implement fetch_<op>/fetch_and_<op>/exchange/compare-and-exchange instructions for BPF. Specially, the following gcc intrinsics are implemented. __sync_fetch_and_add (32, 64) __sync_fetch_and_sub (32, 64) __sync_fetch_and_and (32, 64) __sync_fetch_and_or (32, 64) __sync_fetch_and_xor (32, 64) __sync_lock_test_and_set (32, 64) __sync_val_compare_and_swap (32, 64) For __sync_fetch_and_sub, internally, it is implemented as a negation followed by __sync_fetch_and_add. For __sync_lock_test_and_set, despite its name, it actually does an atomic exchange and return the old content. https://gcc.gnu.org/onlinedocs/gcc-4.1.1/gcc/Atomic-Builtins.html For intrinsics like __sync_{add,sub}_and_fetch and __sync_bool_compare_and_swap, the compiler is able to generate codes using __sync_fetch_and_{add,sub} and __sync_val_compare_and_swap. Similar to xadd, atomic xadd, xor and xxor (atomic_<op>) instructions are added for atomic operations which do not have return values. LLVM will check the return value for __sync_fetch_and_{add,and,or,xor}. If the return value is used, instructions atomic_fetch_<op> will be used. Otherwise, atomic_<op> instructions will be used. All new instructions only support 64bit and 32bit with alu32 mode. old xadd instruction still supports 32bit without alu32 mode. For encoding, please take a look at test atomics_2.ll. Differential Revision: https://reviews.llvm.org/D72184
2020-01-04 04:06:08 +08:00
; CHECK-V3: lock *(u32 *)(r1 + 0) += w2
; CHECK-V3: encoding: [0xc3,0x21,0x00,0x00,0x00,0x00,0x00,0x00]
BPF backend Summary: V8->V9: - cleanup tests V7->V8: - addressed feedback from David: - switched to range-based 'for' loops - fixed formatting of tests V6->V7: - rebased and adjusted AsmPrinter args - CamelCased .td, fixed formatting, cleaned up names, removed unused patterns - diffstat: 3 files changed, 203 insertions(+), 227 deletions(-) V5->V6: - addressed feedback from Chandler: - reinstated full verbose standard banner in all files - fixed variables that were not in CamelCase - fixed names of #ifdef in header files - removed redundant braces in if/else chains with single statements - fixed comments - removed trailing empty line - dropped debug annotations from tests - diffstat of these changes: 46 files changed, 456 insertions(+), 469 deletions(-) V4->V5: - fix setLoadExtAction() interface - clang-formated all where it made sense V3->V4: - added CODE_OWNERS entry for BPF backend V2->V3: - fix metadata in tests V1->V2: - addressed feedback from Tom and Matt - removed top level change to configure (now everything via 'experimental-backend') - reworked error reporting via DiagnosticInfo (similar to R600) - added few more tests - added cmake build - added Triple::bpf - tested on linux and darwin V1 cover letter: --------------------- recently linux gained "universal in-kernel virtual machine" which is called eBPF or extended BPF. The name comes from "Berkeley Packet Filter", since new instruction set is based on it. This patch adds a new backend that emits extended BPF instruction set. The concept and development are covered by the following articles: http://lwn.net/Articles/599755/ http://lwn.net/Articles/575531/ http://lwn.net/Articles/603983/ http://lwn.net/Articles/606089/ http://lwn.net/Articles/612878/ One of use cases: dtrace/systemtap alternative. bpf syscall manpage: https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=b4fc1a460f3017e958e6a8ea560ea0afd91bf6fe instruction set description and differences vs classic BPF: http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/tree/Documentation/networking/filter.txt Short summary of instruction set: - 64-bit registers R0 - return value from in-kernel function, and exit value for BPF program R1 - R5 - arguments from BPF program to in-kernel function R6 - R9 - callee saved registers that in-kernel function will preserve R10 - read-only frame pointer to access stack - two-operand instructions like +, -, *, mov, load/store - implicit prologue/epilogue (invisible stack pointer) - no floating point, no simd Short history of extended BPF in kernel: interpreter in 3.15, x64 JIT in 3.16, arm64 JIT, verifier, bpf syscall in 3.18, more to come in the future. It's a very small and simple backend. There is no support for global variables, arbitrary function calls, floating point, varargs, exceptions, indirect jumps, arbitrary pointer arithmetic, alloca, etc. From C front-end point of view it's very restricted. It's done on purpose, since kernel rejects all programs that it cannot prove safe. It rejects programs with loops and with memory accesses via arbitrary pointers. When kernel accepts the program it is guaranteed that program will terminate and will not crash the kernel. This patch implements all 'must have' bits. There are several things on TODO list, so this is not the end of development. Most of the code is a boiler plate code, copy-pasted from other backends. Only odd things are lack or < and <= instructions, specialized load_byte intrinsics and 'compare and goto' as single instruction. Current instruction set is fixed, but more instructions can be added in the future. Signed-off-by: Alexei Starovoitov <alexei.starovoitov@gmail.com> Subscribers: majnemer, chandlerc, echristo, joerg, pete, rengolin, kristof.beyls, arsenm, t.p.northover, tstellarAMD, aemerson, llvm-commits Differential Revision: http://reviews.llvm.org/D6494 llvm-svn: 227008
2015-01-25 01:51:26 +08:00
define void @test_load_add_32(i32* %p, i32 zeroext %v) {
entry:
atomicrmw add i32* %p, i32 %v seq_cst
ret void
}
; CHECK-LABEL: test_load_add_64
[bpf] add BPF disassembler add BPF disassembler, so tools like llvm-objdump can be used: $ llvm-objdump -d -no-show-raw-insn ./sockex1_kern.o ./sockex1_kern.o: file format ELF64-BPF Disassembly of section socket1: bpf_prog1: 0: r6 = r1 8: r0 = *(u8 *)skb[23] 10: *(u32 *)(r10 - 4) = r0 18: r1 = *(u32 *)(r6 + 4) 20: if r1 != 4 goto 8 28: r2 = r10 30: r2 += -4 ld_imm64 (the only 16-byte insn) and special ld_abs/ld_ind instructions had to be treated in a special way. The decoders for the rest of the insns are automatically generated. Add tests to cover new functionality. Signed-off-by: Alexei Starovoitov <ast@kernel.org> llvm-svn: 287477
2016-11-20 10:25:00 +08:00
; CHECK: lock *(u64 *)(r1 + 0) += r2
; CHECK: encoding: [0xdb,0x21
[BPF] support atomic instructions Implement fetch_<op>/fetch_and_<op>/exchange/compare-and-exchange instructions for BPF. Specially, the following gcc intrinsics are implemented. __sync_fetch_and_add (32, 64) __sync_fetch_and_sub (32, 64) __sync_fetch_and_and (32, 64) __sync_fetch_and_or (32, 64) __sync_fetch_and_xor (32, 64) __sync_lock_test_and_set (32, 64) __sync_val_compare_and_swap (32, 64) For __sync_fetch_and_sub, internally, it is implemented as a negation followed by __sync_fetch_and_add. For __sync_lock_test_and_set, despite its name, it actually does an atomic exchange and return the old content. https://gcc.gnu.org/onlinedocs/gcc-4.1.1/gcc/Atomic-Builtins.html For intrinsics like __sync_{add,sub}_and_fetch and __sync_bool_compare_and_swap, the compiler is able to generate codes using __sync_fetch_and_{add,sub} and __sync_val_compare_and_swap. Similar to xadd, atomic xadd, xor and xxor (atomic_<op>) instructions are added for atomic operations which do not have return values. LLVM will check the return value for __sync_fetch_and_{add,and,or,xor}. If the return value is used, instructions atomic_fetch_<op> will be used. Otherwise, atomic_<op> instructions will be used. All new instructions only support 64bit and 32bit with alu32 mode. old xadd instruction still supports 32bit without alu32 mode. For encoding, please take a look at test atomics_2.ll. Differential Revision: https://reviews.llvm.org/D72184
2020-01-04 04:06:08 +08:00
; CHECK-V3: lock *(u64 *)(r1 + 0) += r2
; CHECK-V3: encoding: [0xdb,0x21,0x00,0x00,0x00,0x00,0x00,0x00]
BPF backend Summary: V8->V9: - cleanup tests V7->V8: - addressed feedback from David: - switched to range-based 'for' loops - fixed formatting of tests V6->V7: - rebased and adjusted AsmPrinter args - CamelCased .td, fixed formatting, cleaned up names, removed unused patterns - diffstat: 3 files changed, 203 insertions(+), 227 deletions(-) V5->V6: - addressed feedback from Chandler: - reinstated full verbose standard banner in all files - fixed variables that were not in CamelCase - fixed names of #ifdef in header files - removed redundant braces in if/else chains with single statements - fixed comments - removed trailing empty line - dropped debug annotations from tests - diffstat of these changes: 46 files changed, 456 insertions(+), 469 deletions(-) V4->V5: - fix setLoadExtAction() interface - clang-formated all where it made sense V3->V4: - added CODE_OWNERS entry for BPF backend V2->V3: - fix metadata in tests V1->V2: - addressed feedback from Tom and Matt - removed top level change to configure (now everything via 'experimental-backend') - reworked error reporting via DiagnosticInfo (similar to R600) - added few more tests - added cmake build - added Triple::bpf - tested on linux and darwin V1 cover letter: --------------------- recently linux gained "universal in-kernel virtual machine" which is called eBPF or extended BPF. The name comes from "Berkeley Packet Filter", since new instruction set is based on it. This patch adds a new backend that emits extended BPF instruction set. The concept and development are covered by the following articles: http://lwn.net/Articles/599755/ http://lwn.net/Articles/575531/ http://lwn.net/Articles/603983/ http://lwn.net/Articles/606089/ http://lwn.net/Articles/612878/ One of use cases: dtrace/systemtap alternative. bpf syscall manpage: https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=b4fc1a460f3017e958e6a8ea560ea0afd91bf6fe instruction set description and differences vs classic BPF: http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/tree/Documentation/networking/filter.txt Short summary of instruction set: - 64-bit registers R0 - return value from in-kernel function, and exit value for BPF program R1 - R5 - arguments from BPF program to in-kernel function R6 - R9 - callee saved registers that in-kernel function will preserve R10 - read-only frame pointer to access stack - two-operand instructions like +, -, *, mov, load/store - implicit prologue/epilogue (invisible stack pointer) - no floating point, no simd Short history of extended BPF in kernel: interpreter in 3.15, x64 JIT in 3.16, arm64 JIT, verifier, bpf syscall in 3.18, more to come in the future. It's a very small and simple backend. There is no support for global variables, arbitrary function calls, floating point, varargs, exceptions, indirect jumps, arbitrary pointer arithmetic, alloca, etc. From C front-end point of view it's very restricted. It's done on purpose, since kernel rejects all programs that it cannot prove safe. It rejects programs with loops and with memory accesses via arbitrary pointers. When kernel accepts the program it is guaranteed that program will terminate and will not crash the kernel. This patch implements all 'must have' bits. There are several things on TODO list, so this is not the end of development. Most of the code is a boiler plate code, copy-pasted from other backends. Only odd things are lack or < and <= instructions, specialized load_byte intrinsics and 'compare and goto' as single instruction. Current instruction set is fixed, but more instructions can be added in the future. Signed-off-by: Alexei Starovoitov <alexei.starovoitov@gmail.com> Subscribers: majnemer, chandlerc, echristo, joerg, pete, rengolin, kristof.beyls, arsenm, t.p.northover, tstellarAMD, aemerson, llvm-commits Differential Revision: http://reviews.llvm.org/D6494 llvm-svn: 227008
2015-01-25 01:51:26 +08:00
define void @test_load_add_64(i64* %p, i64 zeroext %v) {
entry:
atomicrmw add i64* %p, i64 %v seq_cst
ret void
}