From 4e7a65d868de016cde7a8719c64eedcf66cc3405 Mon Sep 17 00:00:00 2001 From: Alex Fan Date: Mon, 29 Aug 2022 15:24:16 +0800 Subject: [PATCH] Enable using llvm jitlink as an alternative llvm jit linker of old Rtdyld. This brings the bonus of support jitting on riscv64 (included in this patch) Assume gc(imafdac) extension since generally it is the expected minimum for linux capable machines Currently(version 16), llvm doesn't expose jitlink (ObjectLinkingLayer) via C API, so a wrapper is added. --- config/llvm.m4 | 1 + src/backend/jit/llvm/llvmjit.c | 59 +++++++++++++++++++++++++-- src/backend/jit/llvm/llvmjit_wrap.cpp | 37 +++++++++++++++++ src/include/jit/llvmjit.h | 9 ++++ 4 files changed, 102 insertions(+), 4 deletions(-) diff --git a/config/llvm.m4 b/config/llvm.m4 index 3a75cd8b4d..a31b8b304a 100644 --- a/config/llvm.m4 +++ b/config/llvm.m4 @@ -75,6 +75,7 @@ AC_DEFUN([PGAC_LLVM_SUPPORT], engine) pgac_components="$pgac_components $pgac_component";; debuginfodwarf) pgac_components="$pgac_components $pgac_component";; orcjit) pgac_components="$pgac_components $pgac_component";; + jitlink) pgac_components="$pgac_components $pgac_component";; passes) pgac_components="$pgac_components $pgac_component";; native) pgac_components="$pgac_components $pgac_component";; perfjitevents) pgac_components="$pgac_components $pgac_component";; diff --git a/src/backend/jit/llvm/llvmjit.c b/src/backend/jit/llvm/llvmjit.c index 312612115c..636f76360e 100644 --- a/src/backend/jit/llvm/llvmjit.c +++ b/src/backend/jit/llvm/llvmjit.c @@ -229,6 +229,11 @@ llvm_release_context(JitContext *context) LLVMModuleRef llvm_mutable_module(LLVMJitContext *context) { +#ifdef __riscv + const char* abiname; + const char* target_abi = "target-abi"; + LLVMMetadataRef abi_metadata; +#endif llvm_assert_in_fatal_section(); /* @@ -241,6 +246,40 @@ llvm_mutable_module(LLVMJitContext *context) context->module = LLVMModuleCreateWithName("pg"); LLVMSetTarget(context->module, llvm_triple); LLVMSetDataLayout(context->module, llvm_layout); +#ifdef __riscv +#if __riscv_xlen == 64 +#ifdef __riscv_float_abi_double + abiname = "lp64d"; +#elif defined(__riscv_float_abi_single) + abiname = "lp64f"; +#else + abiname = "lp64"; +#endif +#elif __riscv_xlen == 32 +#ifdef __riscv_float_abi_double + abiname = "ilp32d"; +#elif defined(__riscv_float_abi_single) + abiname = "ilp32f"; +#else + abiname = "ilp32"; +#endif +#else + elog(ERROR, "unsupported riscv xlen %d", __riscv_xlen); +#endif + /* + * set this manually to avoid llvm defaulting to soft float and + * resulting in linker error: `can't link double-float modules + * with soft-float modules` + * we could set this for TargetMachine via MCOptions, but there + * is no C API for it + * ref: https://github.com/llvm/llvm-project/blob/afa520ab34803c82587ea6759bfd352579f741b4/llvm/lib/Target/RISCV/RISCVTargetMachine.cpp#L90 + */ + abi_metadata = LLVMMDStringInContext2( + LLVMGetModuleContext(context->module), + abiname, strlen(abiname)); + LLVMAddModuleFlag(context->module, LLVMModuleFlagBehaviorOverride, + target_abi, strlen(target_abi), abi_metadata); +#endif } return context->module; @@ -786,6 +825,8 @@ llvm_session_initialize(void) char *error = NULL; char *cpu = NULL; char *features = NULL; + LLVMRelocMode reloc=LLVMRelocDefault; + LLVMCodeModel codemodel=LLVMCodeModelJITDefault; LLVMTargetMachineRef opt0_tm; LLVMTargetMachineRef opt3_tm; @@ -830,16 +871,21 @@ llvm_session_initialize(void) elog(DEBUG2, "LLVMJIT detected CPU \"%s\", with features \"%s\"", cpu, features); +#ifdef __riscv + reloc=LLVMRelocPIC; + codemodel=LLVMCodeModelMedium; +#endif + opt0_tm = LLVMCreateTargetMachine(llvm_targetref, llvm_triple, cpu, features, LLVMCodeGenLevelNone, - LLVMRelocDefault, - LLVMCodeModelJITDefault); + reloc, + codemodel); opt3_tm = LLVMCreateTargetMachine(llvm_targetref, llvm_triple, cpu, features, LLVMCodeGenLevelAggressive, - LLVMRelocDefault, - LLVMCodeModelJITDefault); + reloc, + codemodel); LLVMDisposeMessage(cpu); cpu = NULL; @@ -1174,6 +1220,10 @@ llvm_log_jit_error(void *ctx, LLVMErrorRef error) static LLVMOrcObjectLayerRef llvm_create_object_layer(void *Ctx, LLVMOrcExecutionSessionRef ES, const char *Triple) { +#if defined(USE_JITLINK) + LLVMOrcObjectLayerRef objlayer = + LLVMOrcCreateJitlinkObjectLinkingLayer(ES); +#else LLVMOrcObjectLayerRef objlayer = LLVMOrcCreateRTDyldObjectLinkingLayerWithSectionMemoryManager(ES); @@ -1193,6 +1243,7 @@ llvm_create_object_layer(void *Ctx, LLVMOrcExecutionSessionRef ES, const char *T LLVMOrcRTDyldObjectLinkingLayerRegisterJITEventListener(objlayer, l); } +#endif #endif return objlayer; diff --git a/src/backend/jit/llvm/llvmjit_wrap.cpp b/src/backend/jit/llvm/llvmjit_wrap.cpp index 05199a4956..60e4cd825e 100644 --- a/src/backend/jit/llvm/llvmjit_wrap.cpp +++ b/src/backend/jit/llvm/llvmjit_wrap.cpp @@ -27,6 +27,10 @@ extern "C" #include #include "jit/llvmjit.h" +#ifdef USE_JITLINK +#include "llvm/ExecutionEngine/JITLink/EHFrameSupport.h" +#include "llvm/ExecutionEngine/Orc/ObjectLinkingLayer.h" +#endif /* @@ -48,6 +52,21 @@ char *LLVMGetHostCPUFeatures(void) { for (auto &F : HostFeatures) Features.AddFeature(F.first(), F.second); +#if defined(__riscv) + /* getHostCPUName returns "generic-rv[32|64]", which lacks all features + * except extension 'i' + * Assume running machine support 'rv64imafdc' ('rv64gc') because it is + * the recommended and most common basic set of extensions for running + * linux capable machines. + */ + Features.AddFeature("m", true); + Features.AddFeature("a", true); + Features.AddFeature("c", true); + Features.AddFeature("f", true); + Features.AddFeature("d", true); +# endif +#endif + return strdup(Features.getString().c_str()); } #endif @@ -76,3 +95,21 @@ LLVMGetAttributeCountAtIndexPG(LLVMValueRef F, uint32 Idx) */ return LLVMGetAttributeCountAtIndex(F, Idx); } + +#ifdef USE_JITLINK +/* + * There is no public C API to create ObjectLinkingLayer for JITLINK, create our own + */ +DEFINE_SIMPLE_CONVERSION_FUNCTIONS(llvm::orc::ExecutionSession, LLVMOrcExecutionSessionRef) +DEFINE_SIMPLE_CONVERSION_FUNCTIONS(llvm::orc::ObjectLayer, LLVMOrcObjectLayerRef) + +LLVMOrcObjectLayerRef +LLVMOrcCreateJitlinkObjectLinkingLayer(LLVMOrcExecutionSessionRef ES) +{ + Assert(ES); + auto ObjLinkingLayer = new llvm::orc::ObjectLinkingLayer(*unwrap(ES)); + ObjLinkingLayer->addPlugin(std::make_unique( + *unwrap(ES), std::make_unique())); + return wrap(ObjLinkingLayer); +} +#endif diff --git a/src/include/jit/llvmjit.h b/src/include/jit/llvmjit.h index 551b585464..9f31b33e1c 100644 --- a/src/include/jit/llvmjit.h +++ b/src/include/jit/llvmjit.h @@ -19,6 +19,11 @@ #include +#if defined(__riscv) && LLVM_VERSION_MAJOR >= 15 +#include +#define USE_JITLINK +/* else use legacy RTDyld */ +#endif /* * File needs to be includable by both C and C++ code, and include other @@ -134,6 +139,10 @@ extern char *LLVMGetHostCPUFeatures(void); extern unsigned LLVMGetAttributeCountAtIndexPG(LLVMValueRef F, uint32 Idx); +#ifdef USE_JITLINK +extern LLVMOrcObjectLayerRef LLVMOrcCreateJitlinkObjectLinkingLayer(LLVMOrcExecutionSessionRef ES); +#endif + #ifdef __cplusplus } /* extern "C" */ #endif -- 2.37.3