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Diffstat (limited to 'src/vm/argdestination.h')
-rw-r--r-- | src/vm/argdestination.h | 217 |
1 files changed, 217 insertions, 0 deletions
diff --git a/src/vm/argdestination.h b/src/vm/argdestination.h new file mode 100644 index 0000000000..5896414f35 --- /dev/null +++ b/src/vm/argdestination.h @@ -0,0 +1,217 @@ +// +// Copyright (c) Microsoft. All rights reserved. +// Licensed under the MIT license. See LICENSE file in the project root for full license information. +// +// + +#ifndef __ARGDESTINATION_H__ +#define __ARGDESTINATION_H__ + +// The ArgDestination class represents a destination location of an argument. +class ArgDestination +{ + // Base address to which the m_offset is applied to get the actual argument location. + PTR_VOID m_base; + // Offset of the argument relative to the m_base. On AMD64 on Unix, it can have a special + // value that represent a struct that contain both general purpose and floating point fields + // passed in registers. + int m_offset; + // For structs passed in registers, this member points to an ArgLocDesc that contains + // details on the layout of the struct in general purpose and floating point registers. + ArgLocDesc* m_argLocDescForStructInRegs; + +public: + + // Construct the ArgDestination + ArgDestination(PTR_VOID base, int offset, ArgLocDesc* argLocDescForStructInRegs) + : m_base(base), + m_offset(offset), + m_argLocDescForStructInRegs(argLocDescForStructInRegs) + { + LIMITED_METHOD_CONTRACT; +#if defined(UNIX_AMD64_ABI) && defined(FEATURE_UNIX_AMD64_STRUCT_PASSING) + _ASSERTE((argLocDescForStructInRegs != NULL) || (offset != TransitionBlock::StructInRegsOffset)); +#else + _ASSERTE(argLocDescForStructInRegs == NULL); +#endif + } + + // Get argument destination address for arguments that are not structs passed in registers. + PTR_VOID GetDestinationAddress() + { + LIMITED_METHOD_CONTRACT; + return dac_cast<PTR_VOID>(dac_cast<TADDR>(m_base) + m_offset); + } + +#if defined(UNIX_AMD64_ABI) && defined(FEATURE_UNIX_AMD64_STRUCT_PASSING) + + // Returns true if the ArgDestination represents a struct passed in registers. + bool IsStructPassedInRegs() + { + LIMITED_METHOD_CONTRACT; + return m_offset == TransitionBlock::StructInRegsOffset; + } + + // Get destination address for floating point fields of a struct passed in registers. + PTR_VOID GetStructFloatRegDestinationAddress() + { + LIMITED_METHOD_CONTRACT; + _ASSERTE(IsStructPassedInRegs()); + int offset = TransitionBlock::GetOffsetOfFloatArgumentRegisters() + m_argLocDescForStructInRegs->m_idxFloatReg * 8; + return dac_cast<PTR_VOID>(dac_cast<TADDR>(m_base) + offset); + } + + // Get destination address for non-floating point fields of a struct passed in registers. + PTR_VOID GetStructGenRegDestinationAddress() + { + LIMITED_METHOD_CONTRACT; + _ASSERTE(IsStructPassedInRegs()); + int offset = TransitionBlock::GetOffsetOfArgumentRegisters() + m_argLocDescForStructInRegs->m_idxGenReg * 8; + return dac_cast<PTR_VOID>(dac_cast<TADDR>(m_base) + offset); + } + +#ifndef DACCESS_COMPILE + // Zero struct argument stored in registers described by the current ArgDestination. + // Arguments: + // fieldBytes - size of the structure + void ZeroStructInRegisters(int fieldBytes) + { + STATIC_CONTRACT_NOTHROW; + STATIC_CONTRACT_GC_NOTRIGGER; + STATIC_CONTRACT_FORBID_FAULT; + STATIC_CONTRACT_MODE_COOPERATIVE; + + // To zero the struct, we create a zero filled array of large enough size and + // then copy it to the registers. It is implemented this way to keep the complexity + // of dealing with the eightbyte classification in single function. + // This function is used rarely and so the overhead of reading the zeros from + // the stack is negligible. + long long zeros[CLR_SYSTEMV_MAX_EIGHTBYTES_COUNT_TO_PASS_IN_REGISTERS] = {}; + _ASSERTE(sizeof(zeros) >= fieldBytes); + + CopyStructToRegisters(zeros, fieldBytes, 0); + } + + // Copy struct argument into registers described by the current ArgDestination. + // Arguments: + // src = source data of the structure + // fieldBytes - size of the structure + // destOffset - nonzero when copying values into Nullable<T>, it is the offset + // of the T value inside of the Nullable<T> + void CopyStructToRegisters(void *src, int fieldBytes, int destOffset) + { + STATIC_CONTRACT_NOTHROW; + STATIC_CONTRACT_GC_NOTRIGGER; + STATIC_CONTRACT_FORBID_FAULT; + STATIC_CONTRACT_MODE_COOPERATIVE; + + _ASSERTE(IsStructPassedInRegs()); + + BYTE* genRegDest = (BYTE*)GetStructGenRegDestinationAddress() + destOffset; + BYTE* floatRegDest = (BYTE*)GetStructFloatRegDestinationAddress(); + INDEBUG(int remainingBytes = fieldBytes;) + + EEClass* eeClass = m_argLocDescForStructInRegs->m_eeClass; + _ASSERTE(eeClass != NULL); + + // We start at the first eightByte that the destOffset didn't skip completely. + for (int i = destOffset / 8; i < eeClass->GetNumberEightBytes(); i++) + { + int eightByteSize = eeClass->GetEightByteSize(i); + SystemVClassificationType eightByteClassification = eeClass->GetEightByteClassification(i); + + // Adjust the size of the first eightByte by the destOffset + eightByteSize -= (destOffset & 7); + destOffset = 0; + + _ASSERTE(remainingBytes >= eightByteSize); + + if (eightByteClassification == SystemVClassificationTypeSSE) + { + if (eightByteSize == 8) + { + *(UINT64*)floatRegDest = *(UINT64*)src; + } + else + { + _ASSERTE(eightByteSize == 4); + *(UINT32*)floatRegDest = *(UINT32*)src; + } + floatRegDest += 8; + } + else + { + if (eightByteSize == 8) + { + _ASSERTE((eightByteClassification == SystemVClassificationTypeInteger) || + (eightByteClassification == SystemVClassificationTypeIntegerReference)); + + _ASSERTE(IS_ALIGNED((SIZE_T)genRegDest, 8)); + *(UINT64*)genRegDest = *(UINT64*)src; + } + else + { + _ASSERTE(eightByteClassification == SystemVClassificationTypeInteger); + memcpyNoGCRefs(genRegDest, src, eightByteSize); + } + + genRegDest += eightByteSize; + } + + src = (BYTE*)src + eightByteSize; + INDEBUG(remainingBytes -= eightByteSize;) + } + + _ASSERTE(remainingBytes == 0); + } + +#endif //DACCESS_COMPILE + + // Report managed object pointers in the struct in registers + // Arguments: + // fn - promotion function to apply to each managed object pointer + // sc - scan context to pass to the promotion function + // fieldBytes - size of the structure + void ReportPointersFromStructInRegisters(promote_func *fn, ScanContext *sc, int fieldBytes) + { + LIMITED_METHOD_CONTRACT; + + _ASSERTE(IsStructPassedInRegs()); + + TADDR genRegDest = dac_cast<TADDR>(GetStructGenRegDestinationAddress()); + INDEBUG(int remainingBytes = fieldBytes;) + + EEClass* eeClass = m_argLocDescForStructInRegs->m_eeClass; + _ASSERTE(eeClass != NULL); + + for (int i = 0; i < eeClass->GetNumberEightBytes(); i++) + { + int eightByteSize = eeClass->GetEightByteSize(i); + SystemVClassificationType eightByteClassification = eeClass->GetEightByteClassification(i); + + _ASSERTE(remainingBytes >= eightByteSize); + + if (eightByteClassification != SystemVClassificationTypeSSE) + { + if (eightByteClassification == SystemVClassificationTypeIntegerReference) + { + _ASSERTE(eightByteSize == 8); + _ASSERTE(IS_ALIGNED((SIZE_T)genRegDest, 8)); + + (*fn)(dac_cast<PTR_PTR_Object>(genRegDest), sc, 0); + } + + genRegDest += eightByteSize; + } + + INDEBUG(remainingBytes -= eightByteSize;) + } + + _ASSERTE(remainingBytes == 0); + } + +#endif // UNIX_AMD64_ABI && FEATURE_UNIX_AMD64_STRUCT_PASSING + +}; + +#endif // __ARGDESTINATION_H__ |