llvm-project/llvm/lib/Target/BPF/BPFSubtarget.cpp

64 lines
1.8 KiB
C++
Raw Normal View History

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
//===-- BPFSubtarget.cpp - BPF Subtarget Information ----------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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
//
//===----------------------------------------------------------------------===//
//
// This file implements the BPF specific subclass of TargetSubtargetInfo.
//
//===----------------------------------------------------------------------===//
#include "BPFSubtarget.h"
#include "BPF.h"
bpf: add variants of -mcpu=# and support for additional jmp insns -mcpu=# will support: . generic: the default insn set . v1: insn set version 1, the same as generic . v2: insn set version 2, version 1 + additional jmp insns . probe: the compiler will probe the underlying kernel to decide proper version of insn set. We did not not use -mcpu=native since llc/llvm will interpret -mcpu=native as the underlying hardware architecture regardless of -march value. Currently, only x86_64 supports -mcpu=probe. Other architecture will silently revert to "generic". Also added -mcpu=help to print available cpu parameters. llvm will print out the information only if there are at least one cpu and at least one feature. Add an unused dummy feature to enable the printout. Examples for usage: $ llc -march=bpf -mcpu=v1 -filetype=asm t.ll $ llc -march=bpf -mcpu=v2 -filetype=asm t.ll $ llc -march=bpf -mcpu=generic -filetype=asm t.ll $ llc -march=bpf -mcpu=probe -filetype=asm t.ll $ llc -march=bpf -mcpu=v3 -filetype=asm t.ll 'v3' is not a recognized processor for this target (ignoring processor) ... $ llc -march=bpf -mcpu=help -filetype=asm t.ll Available CPUs for this target: generic - Select the generic processor. probe - Select the probe processor. v1 - Select the v1 processor. v2 - Select the v2 processor. Available features for this target: dummy - unused feature. Use +feature to enable a feature, or -feature to disable it. For example, llc -mcpu=mycpu -mattr=+feature1,-feature2 ... Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Yonghong Song <yhs@fb.com> Acked-by: Alexei Starovoitov <ast@kernel.org> llvm-svn: 311522
2017-08-23 12:25:57 +08:00
#include "llvm/Support/Host.h"
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
#include "llvm/Support/TargetRegistry.h"
using namespace llvm;
#define DEBUG_TYPE "bpf-subtarget"
#define GET_SUBTARGETINFO_TARGET_DESC
#define GET_SUBTARGETINFO_CTOR
#include "BPFGenSubtargetInfo.inc"
void BPFSubtarget::anchor() {}
bpf: add variants of -mcpu=# and support for additional jmp insns -mcpu=# will support: . generic: the default insn set . v1: insn set version 1, the same as generic . v2: insn set version 2, version 1 + additional jmp insns . probe: the compiler will probe the underlying kernel to decide proper version of insn set. We did not not use -mcpu=native since llc/llvm will interpret -mcpu=native as the underlying hardware architecture regardless of -march value. Currently, only x86_64 supports -mcpu=probe. Other architecture will silently revert to "generic". Also added -mcpu=help to print available cpu parameters. llvm will print out the information only if there are at least one cpu and at least one feature. Add an unused dummy feature to enable the printout. Examples for usage: $ llc -march=bpf -mcpu=v1 -filetype=asm t.ll $ llc -march=bpf -mcpu=v2 -filetype=asm t.ll $ llc -march=bpf -mcpu=generic -filetype=asm t.ll $ llc -march=bpf -mcpu=probe -filetype=asm t.ll $ llc -march=bpf -mcpu=v3 -filetype=asm t.ll 'v3' is not a recognized processor for this target (ignoring processor) ... $ llc -march=bpf -mcpu=help -filetype=asm t.ll Available CPUs for this target: generic - Select the generic processor. probe - Select the probe processor. v1 - Select the v1 processor. v2 - Select the v2 processor. Available features for this target: dummy - unused feature. Use +feature to enable a feature, or -feature to disable it. For example, llc -mcpu=mycpu -mattr=+feature1,-feature2 ... Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Yonghong Song <yhs@fb.com> Acked-by: Alexei Starovoitov <ast@kernel.org> llvm-svn: 311522
2017-08-23 12:25:57 +08:00
BPFSubtarget &BPFSubtarget::initializeSubtargetDependencies(StringRef CPU,
StringRef FS) {
initializeEnvironment();
initSubtargetFeatures(CPU, FS);
ParseSubtargetFeatures(CPU, FS);
bpf: add variants of -mcpu=# and support for additional jmp insns -mcpu=# will support: . generic: the default insn set . v1: insn set version 1, the same as generic . v2: insn set version 2, version 1 + additional jmp insns . probe: the compiler will probe the underlying kernel to decide proper version of insn set. We did not not use -mcpu=native since llc/llvm will interpret -mcpu=native as the underlying hardware architecture regardless of -march value. Currently, only x86_64 supports -mcpu=probe. Other architecture will silently revert to "generic". Also added -mcpu=help to print available cpu parameters. llvm will print out the information only if there are at least one cpu and at least one feature. Add an unused dummy feature to enable the printout. Examples for usage: $ llc -march=bpf -mcpu=v1 -filetype=asm t.ll $ llc -march=bpf -mcpu=v2 -filetype=asm t.ll $ llc -march=bpf -mcpu=generic -filetype=asm t.ll $ llc -march=bpf -mcpu=probe -filetype=asm t.ll $ llc -march=bpf -mcpu=v3 -filetype=asm t.ll 'v3' is not a recognized processor for this target (ignoring processor) ... $ llc -march=bpf -mcpu=help -filetype=asm t.ll Available CPUs for this target: generic - Select the generic processor. probe - Select the probe processor. v1 - Select the v1 processor. v2 - Select the v2 processor. Available features for this target: dummy - unused feature. Use +feature to enable a feature, or -feature to disable it. For example, llc -mcpu=mycpu -mattr=+feature1,-feature2 ... Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Yonghong Song <yhs@fb.com> Acked-by: Alexei Starovoitov <ast@kernel.org> llvm-svn: 311522
2017-08-23 12:25:57 +08:00
return *this;
}
void BPFSubtarget::initializeEnvironment() {
HasJmpExt = false;
HasJmp32 = false;
HasAlu32 = false;
UseDwarfRIS = false;
bpf: add variants of -mcpu=# and support for additional jmp insns -mcpu=# will support: . generic: the default insn set . v1: insn set version 1, the same as generic . v2: insn set version 2, version 1 + additional jmp insns . probe: the compiler will probe the underlying kernel to decide proper version of insn set. We did not not use -mcpu=native since llc/llvm will interpret -mcpu=native as the underlying hardware architecture regardless of -march value. Currently, only x86_64 supports -mcpu=probe. Other architecture will silently revert to "generic". Also added -mcpu=help to print available cpu parameters. llvm will print out the information only if there are at least one cpu and at least one feature. Add an unused dummy feature to enable the printout. Examples for usage: $ llc -march=bpf -mcpu=v1 -filetype=asm t.ll $ llc -march=bpf -mcpu=v2 -filetype=asm t.ll $ llc -march=bpf -mcpu=generic -filetype=asm t.ll $ llc -march=bpf -mcpu=probe -filetype=asm t.ll $ llc -march=bpf -mcpu=v3 -filetype=asm t.ll 'v3' is not a recognized processor for this target (ignoring processor) ... $ llc -march=bpf -mcpu=help -filetype=asm t.ll Available CPUs for this target: generic - Select the generic processor. probe - Select the probe processor. v1 - Select the v1 processor. v2 - Select the v2 processor. Available features for this target: dummy - unused feature. Use +feature to enable a feature, or -feature to disable it. For example, llc -mcpu=mycpu -mattr=+feature1,-feature2 ... Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Yonghong Song <yhs@fb.com> Acked-by: Alexei Starovoitov <ast@kernel.org> llvm-svn: 311522
2017-08-23 12:25:57 +08:00
}
void BPFSubtarget::initSubtargetFeatures(StringRef CPU, StringRef FS) {
if (CPU == "probe")
CPU = sys::detail::getHostCPUNameForBPF();
if (CPU == "generic" || CPU == "v1")
return;
if (CPU == "v2") {
HasJmpExt = true;
return;
}
if (CPU == "v3") {
HasJmpExt = true;
HasJmp32 = true;
return;
}
bpf: add variants of -mcpu=# and support for additional jmp insns -mcpu=# will support: . generic: the default insn set . v1: insn set version 1, the same as generic . v2: insn set version 2, version 1 + additional jmp insns . probe: the compiler will probe the underlying kernel to decide proper version of insn set. We did not not use -mcpu=native since llc/llvm will interpret -mcpu=native as the underlying hardware architecture regardless of -march value. Currently, only x86_64 supports -mcpu=probe. Other architecture will silently revert to "generic". Also added -mcpu=help to print available cpu parameters. llvm will print out the information only if there are at least one cpu and at least one feature. Add an unused dummy feature to enable the printout. Examples for usage: $ llc -march=bpf -mcpu=v1 -filetype=asm t.ll $ llc -march=bpf -mcpu=v2 -filetype=asm t.ll $ llc -march=bpf -mcpu=generic -filetype=asm t.ll $ llc -march=bpf -mcpu=probe -filetype=asm t.ll $ llc -march=bpf -mcpu=v3 -filetype=asm t.ll 'v3' is not a recognized processor for this target (ignoring processor) ... $ llc -march=bpf -mcpu=help -filetype=asm t.ll Available CPUs for this target: generic - Select the generic processor. probe - Select the probe processor. v1 - Select the v1 processor. v2 - Select the v2 processor. Available features for this target: dummy - unused feature. Use +feature to enable a feature, or -feature to disable it. For example, llc -mcpu=mycpu -mattr=+feature1,-feature2 ... Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Yonghong Song <yhs@fb.com> Acked-by: Alexei Starovoitov <ast@kernel.org> llvm-svn: 311522
2017-08-23 12:25:57 +08:00
}
BPFSubtarget::BPFSubtarget(const Triple &TT, const std::string &CPU,
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
const std::string &FS, const TargetMachine &TM)
bpf: add variants of -mcpu=# and support for additional jmp insns -mcpu=# will support: . generic: the default insn set . v1: insn set version 1, the same as generic . v2: insn set version 2, version 1 + additional jmp insns . probe: the compiler will probe the underlying kernel to decide proper version of insn set. We did not not use -mcpu=native since llc/llvm will interpret -mcpu=native as the underlying hardware architecture regardless of -march value. Currently, only x86_64 supports -mcpu=probe. Other architecture will silently revert to "generic". Also added -mcpu=help to print available cpu parameters. llvm will print out the information only if there are at least one cpu and at least one feature. Add an unused dummy feature to enable the printout. Examples for usage: $ llc -march=bpf -mcpu=v1 -filetype=asm t.ll $ llc -march=bpf -mcpu=v2 -filetype=asm t.ll $ llc -march=bpf -mcpu=generic -filetype=asm t.ll $ llc -march=bpf -mcpu=probe -filetype=asm t.ll $ llc -march=bpf -mcpu=v3 -filetype=asm t.ll 'v3' is not a recognized processor for this target (ignoring processor) ... $ llc -march=bpf -mcpu=help -filetype=asm t.ll Available CPUs for this target: generic - Select the generic processor. probe - Select the probe processor. v1 - Select the v1 processor. v2 - Select the v2 processor. Available features for this target: dummy - unused feature. Use +feature to enable a feature, or -feature to disable it. For example, llc -mcpu=mycpu -mattr=+feature1,-feature2 ... Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Yonghong Song <yhs@fb.com> Acked-by: Alexei Starovoitov <ast@kernel.org> llvm-svn: 311522
2017-08-23 12:25:57 +08:00
: BPFGenSubtargetInfo(TT, CPU, FS), InstrInfo(),
FrameLowering(initializeSubtargetDependencies(CPU, FS)),
TLInfo(TM, *this) {}