mirror of
https://github.com/c64scene-ar/llvm-6502.git
synced 2024-12-26 21:32:10 +00:00
f70f3d4708
The byte has no endianness, so these types don't make sense. uint8_t should be used instead. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217631 91177308-0d34-0410-b5e6-96231b3b80d8
383 lines
16 KiB
C++
383 lines
16 KiB
C++
//===-- llvm/Support/WinARMEH.h - Windows on ARM EH Constants ---*- C++ -*-===//
|
|
//
|
|
// The LLVM Compiler Infrastructure
|
|
//
|
|
// This file is distributed under the University of Illinois Open Source
|
|
// License. See LICENSE.TXT for details.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#ifndef LLVM_SUPPORT_ARMWINEH_H
|
|
#define LLVM_SUPPORT_ARMWINEH_H
|
|
|
|
#include "llvm/ADT/ArrayRef.h"
|
|
#include "llvm/Support/Endian.h"
|
|
|
|
namespace llvm {
|
|
namespace ARM {
|
|
namespace WinEH {
|
|
enum class RuntimeFunctionFlag {
|
|
RFF_Unpacked, /// unpacked entry
|
|
RFF_Packed, /// packed entry
|
|
RFF_PackedFragment, /// packed entry representing a fragment
|
|
RFF_Reserved, /// reserved
|
|
};
|
|
|
|
enum class ReturnType {
|
|
RT_POP, /// return via pop {pc} (L flag must be set)
|
|
RT_B, /// 16-bit branch
|
|
RT_BW, /// 32-bit branch
|
|
RT_NoEpilogue, /// no epilogue (fragment)
|
|
};
|
|
|
|
/// RuntimeFunction - An entry in the table of procedure data (.pdata)
|
|
///
|
|
/// 3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0
|
|
/// 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0
|
|
/// +---------------------------------------------------------------+
|
|
/// | Function Start RVA |
|
|
/// +-------------------+-+-+-+-----+-+---+---------------------+---+
|
|
/// | Stack Adjust |C|L|R| Reg |H|Ret| Function Length |Flg|
|
|
/// +-------------------+-+-+-+-----+-+---+---------------------+---+
|
|
///
|
|
/// Flag : 2-bit field with the following meanings:
|
|
/// - 00 = packed unwind data not used; reamining bits point to .xdata record
|
|
/// - 01 = packed unwind data
|
|
/// - 10 = packed unwind data, function assumed to have no prologue; useful
|
|
/// for function fragments that are discontiguous with the start of the
|
|
/// function
|
|
/// - 11 = reserved
|
|
/// Function Length : 11-bit field providing the length of the entire function
|
|
/// in bytes, divided by 2; if the function is greater than
|
|
/// 4KB, a full .xdata record must be used instead
|
|
/// Ret : 2-bit field indicating how the function returns
|
|
/// - 00 = return via pop {pc} (the L bit must be set)
|
|
/// - 01 = return via 16-bit branch
|
|
/// - 10 = return via 32-bit branch
|
|
/// - 11 = no epilogue; useful for function fragments that may only contain a
|
|
/// prologue but the epilogue is elsewhere
|
|
/// H : 1-bit flag indicating whether the function "homes" the integer parameter
|
|
/// registers (r0-r3), allocating 16-bytes on the stack
|
|
/// Reg : 3-bit field indicating the index of the last saved non-volatile
|
|
/// register. If the R bit is set to 0, then only integer registers are
|
|
/// saved (r4-rN, where N is 4 + Reg). If the R bit is set to 1, then
|
|
/// only floating-point registers are being saved (d8-dN, where N is
|
|
/// 8 + Reg). The special case of the R bit being set to 1 and Reg equal
|
|
/// to 7 indicates that no registers are saved.
|
|
/// R : 1-bit flag indicating whether the non-volatile registers are integer or
|
|
/// floating-point. 0 indicates integer, 1 indicates floating-point. The
|
|
/// special case of the R-flag being set and Reg being set to 7 indicates
|
|
/// that no non-volatile registers are saved.
|
|
/// L : 1-bit flag indicating whether the function saves/restores the link
|
|
/// register (LR)
|
|
/// C : 1-bit flag indicating whether the function includes extra instructions
|
|
/// to setup a frame chain for fast walking. If this flag is set, r11 is
|
|
/// implicitly added to the list of saved non-volatile integer registers.
|
|
/// Stack Adjust : 10-bit field indicating the number of bytes of stack that are
|
|
/// allocated for this function. Only values between 0x000 and
|
|
/// 0x3f3 can be directly encoded. If the value is 0x3f4 or
|
|
/// greater, then the low 4 bits have special meaning as follows:
|
|
/// - Bit 0-1
|
|
/// indicate the number of words' of adjustment (1-4), minus 1
|
|
/// - Bit 2
|
|
/// indicates if the prologue combined adjustment into push
|
|
/// - Bit 3
|
|
/// indicates if the epilogue combined adjustment into pop
|
|
///
|
|
/// RESTRICTIONS:
|
|
/// - IF C is SET:
|
|
/// + L flag must be set since frame chaining requires r11 and lr
|
|
/// + r11 must NOT be included in the set of registers described by Reg
|
|
/// - IF Ret is 0:
|
|
/// + L flag must be set
|
|
|
|
// NOTE: RuntimeFunction is meant to be a simple class that provides raw access
|
|
// to all fields in the structure. The accessor methods reflect the names of
|
|
// the bitfields that they correspond to. Although some obvious simplifications
|
|
// are possible via merging of methods, it would prevent the use of this class
|
|
// to fully inspect the contents of the data structure which is particularly
|
|
// useful for scenarios such as llvm-readobj to aid in testing.
|
|
|
|
class RuntimeFunction {
|
|
public:
|
|
const support::ulittle32_t BeginAddress;
|
|
const support::ulittle32_t UnwindData;
|
|
|
|
RuntimeFunction(const support::ulittle32_t *Data)
|
|
: BeginAddress(Data[0]), UnwindData(Data[1]) {}
|
|
|
|
RuntimeFunction(const support::ulittle32_t BeginAddress,
|
|
const support::ulittle32_t UnwindData)
|
|
: BeginAddress(BeginAddress), UnwindData(UnwindData) {}
|
|
|
|
RuntimeFunctionFlag Flag() const {
|
|
return RuntimeFunctionFlag(UnwindData & 0x3);
|
|
}
|
|
|
|
uint32_t ExceptionInformationRVA() const {
|
|
assert(Flag() == RuntimeFunctionFlag::RFF_Unpacked &&
|
|
"unpacked form required for this operation");
|
|
return (UnwindData & ~0x3);
|
|
}
|
|
|
|
uint32_t PackedUnwindData() const {
|
|
assert((Flag() == RuntimeFunctionFlag::RFF_Packed ||
|
|
Flag() == RuntimeFunctionFlag::RFF_PackedFragment) &&
|
|
"packed form required for this operation");
|
|
return (UnwindData & ~0x3);
|
|
}
|
|
uint32_t FunctionLength() const {
|
|
assert((Flag() == RuntimeFunctionFlag::RFF_Packed ||
|
|
Flag() == RuntimeFunctionFlag::RFF_PackedFragment) &&
|
|
"packed form required for this operation");
|
|
return (((UnwindData & 0x00001ffc) >> 2) << 1);
|
|
}
|
|
ReturnType Ret() const {
|
|
assert((Flag() == RuntimeFunctionFlag::RFF_Packed ||
|
|
Flag() == RuntimeFunctionFlag::RFF_PackedFragment) &&
|
|
"packed form required for this operation");
|
|
assert(((UnwindData & 0x00006000) || L()) && "L must be set to 1");
|
|
return ReturnType((UnwindData & 0x00006000) >> 13);
|
|
}
|
|
bool H() const {
|
|
assert((Flag() == RuntimeFunctionFlag::RFF_Packed ||
|
|
Flag() == RuntimeFunctionFlag::RFF_PackedFragment) &&
|
|
"packed form required for this operation");
|
|
return ((UnwindData & 0x00008000) >> 15);
|
|
}
|
|
uint8_t Reg() const {
|
|
assert((Flag() == RuntimeFunctionFlag::RFF_Packed ||
|
|
Flag() == RuntimeFunctionFlag::RFF_PackedFragment) &&
|
|
"packed form required for this operation");
|
|
return ((UnwindData & 0x00070000) >> 16);
|
|
}
|
|
bool R() const {
|
|
assert((Flag() == RuntimeFunctionFlag::RFF_Packed ||
|
|
Flag() == RuntimeFunctionFlag::RFF_PackedFragment) &&
|
|
"packed form required for this operation");
|
|
return ((UnwindData & 0x00080000) >> 19);
|
|
}
|
|
bool L() const {
|
|
assert((Flag() == RuntimeFunctionFlag::RFF_Packed ||
|
|
Flag() == RuntimeFunctionFlag::RFF_PackedFragment) &&
|
|
"packed form required for this operation");
|
|
return ((UnwindData & 0x00100000) >> 20);
|
|
}
|
|
bool C() const {
|
|
assert((Flag() == RuntimeFunctionFlag::RFF_Packed ||
|
|
Flag() == RuntimeFunctionFlag::RFF_PackedFragment) &&
|
|
"packed form required for this operation");
|
|
assert(((~UnwindData & 0x00200000) || L()) &&
|
|
"L flag must be set, chaining requires r11 and LR");
|
|
assert(((~UnwindData & 0x00200000) || (Reg() < 7) || R()) &&
|
|
"r11 must not be included in Reg; C implies r11");
|
|
return ((UnwindData & 0x00200000) >> 21);
|
|
}
|
|
uint16_t StackAdjust() const {
|
|
assert((Flag() == RuntimeFunctionFlag::RFF_Packed ||
|
|
Flag() == RuntimeFunctionFlag::RFF_PackedFragment) &&
|
|
"packed form required for this operation");
|
|
return ((UnwindData & 0xffc00000) >> 22);
|
|
}
|
|
};
|
|
|
|
/// PrologueFolding - pseudo-flag derived from Stack Adjust indicating that the
|
|
/// prologue has stack adjustment combined into the push
|
|
inline bool PrologueFolding(const RuntimeFunction &RF) {
|
|
return RF.StackAdjust() >= 0x3f4 && (RF.StackAdjust() & 0x4);
|
|
}
|
|
/// Epilogue - pseudo-flag derived from Stack Adjust indicating that the
|
|
/// epilogue has stack adjustment combined into the pop
|
|
inline bool EpilogueFolding(const RuntimeFunction &RF) {
|
|
return RF.StackAdjust() >= 0x3f4 && (RF.StackAdjust() & 0x8);
|
|
}
|
|
/// StackAdjustment - calculated stack adjustment in words. The stack
|
|
/// adjustment should be determined via this function to account for the special
|
|
/// handling the special encoding when the value is >= 0x3f4.
|
|
inline uint16_t StackAdjustment(const RuntimeFunction &RF) {
|
|
uint16_t Adjustment = RF.StackAdjust();
|
|
if (Adjustment >= 0x3f4)
|
|
return (Adjustment & 0x3) ? ((Adjustment & 0x3) << 2) - 1 : 0;
|
|
return Adjustment;
|
|
}
|
|
|
|
/// SavedRegisterMask - Utility function to calculate the set of saved general
|
|
/// purpose (r0-r15) and VFP (d0-d31) registers.
|
|
std::pair<uint16_t, uint32_t> SavedRegisterMask(const RuntimeFunction &RF);
|
|
|
|
/// ExceptionDataRecord - An entry in the table of exception data (.xdata)
|
|
///
|
|
/// 3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0
|
|
/// 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0
|
|
/// +-------+---------+-+-+-+---+-----------------------------------+
|
|
/// | C Wrd | Epi Cnt |F|E|X|Ver| Function Length |
|
|
/// +-------+--------+'-'-'-'---'---+-------------------------------+
|
|
/// | Reserved |Ex. Code Words| (Extended Epilogue Count) |
|
|
/// +-------+--------+--------------+-------------------------------+
|
|
///
|
|
/// Function Length : 18-bit field indicating the total length of the function
|
|
/// in bytes divided by 2. If a function is larger than
|
|
/// 512KB, then multiple pdata and xdata records must be used.
|
|
/// Vers : 2-bit field describing the version of the remaining structure. Only
|
|
/// version 0 is currently defined (values 1-3 are not permitted).
|
|
/// X : 1-bit field indicating the presence of exception data
|
|
/// E : 1-bit field indicating that the single epilogue is packed into the
|
|
/// header
|
|
/// F : 1-bit field indicating that the record describes a function fragment
|
|
/// (implies that no prologue is present, and prologue processing should be
|
|
/// skipped)
|
|
/// Epilogue Count : 5-bit field that differs in meaning based on the E field.
|
|
///
|
|
/// If E is set, then this field specifies the index of the
|
|
/// first unwind code describing the (only) epilogue.
|
|
///
|
|
/// Otherwise, this field indicates the number of exception
|
|
/// scopes. If more than 31 scopes exist, then this field and
|
|
/// the Code Words field must both be set to 0 to indicate that
|
|
/// an extension word is required.
|
|
/// Code Words : 4-bit field that species the number of 32-bit words needed to
|
|
/// contain all the unwind codes. If more than 15 words (63 code
|
|
/// bytes) are required, then this field and the Epilogue Count
|
|
/// field must both be set to 0 to indicate that an extension word
|
|
/// is required.
|
|
/// Extended Epilogue Count, Extended Code Words :
|
|
/// Valid only if Epilog Count and Code Words are both
|
|
/// set to 0. Provides an 8-bit extended code word
|
|
/// count and 16-bits for epilogue count
|
|
///
|
|
/// 3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0
|
|
/// 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0
|
|
/// +----------------+------+---+---+-------------------------------+
|
|
/// | Ep Start Idx | Cond |Res| Epilogue Start Offset |
|
|
/// +----------------+------+---+-----------------------------------+
|
|
///
|
|
/// If the E bit is unset in the header, the header is followed by a series of
|
|
/// epilogue scopes, which are sorted by their offset.
|
|
///
|
|
/// Epilogue Start Offset: 18-bit field encoding the offset of epilogue relative
|
|
/// to the start of the function in bytes divided by two
|
|
/// Res : 2-bit field reserved for future expansion (must be set to 0)
|
|
/// Condition : 4-bit field providing the condition under which the epilogue is
|
|
/// executed. Unconditional epilogues should set this field to 0xe.
|
|
/// Epilogues must be entirely conditional or unconditional, and in
|
|
/// Thumb-2 mode. The epilogue beings with the first instruction
|
|
/// after the IT opcode.
|
|
/// Epilogue Start Index : 8-bit field indicating the byte index of the first
|
|
/// unwind code describing the epilogue
|
|
///
|
|
/// 3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0
|
|
/// 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0
|
|
/// +---------------+---------------+---------------+---------------+
|
|
/// | Unwind Code 3 | Unwind Code 2 | Unwind Code 1 | Unwind Code 0 |
|
|
/// +---------------+---------------+---------------+---------------+
|
|
///
|
|
/// Following the epilogue scopes, the byte code describing the unwinding
|
|
/// follows. This is padded to align up to word alignment. Bytes are stored in
|
|
/// little endian.
|
|
///
|
|
/// 3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0
|
|
/// 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0
|
|
/// +---------------------------------------------------------------+
|
|
/// | Exception Handler RVA (requires X = 1) |
|
|
/// +---------------------------------------------------------------+
|
|
/// | (possibly followed by data required for exception handler) |
|
|
/// +---------------------------------------------------------------+
|
|
///
|
|
/// If the X bit is set in the header, the unwind byte code is followed by the
|
|
/// exception handler information. This constants of one Exception Handler RVA
|
|
/// which is the address to the exception handler, followed immediately by the
|
|
/// variable length data associated with the exception handler.
|
|
///
|
|
|
|
struct EpilogueScope {
|
|
const support::ulittle32_t ES;
|
|
|
|
EpilogueScope(const support::ulittle32_t Data) : ES(Data) {}
|
|
uint32_t EpilogueStartOffset() const {
|
|
return (ES & 0x0003ffff);
|
|
}
|
|
uint8_t Res() const {
|
|
return ((ES & 0x000c0000) >> 18);
|
|
}
|
|
uint8_t Condition() const {
|
|
return ((ES & 0x00f00000) >> 20);
|
|
}
|
|
uint8_t EpilogueStartIndex() const {
|
|
return ((ES & 0xff000000) >> 24);
|
|
}
|
|
};
|
|
|
|
struct ExceptionDataRecord;
|
|
inline size_t HeaderWords(const ExceptionDataRecord &XR);
|
|
|
|
struct ExceptionDataRecord {
|
|
const support::ulittle32_t *Data;
|
|
|
|
ExceptionDataRecord(const support::ulittle32_t *Data) : Data(Data) {}
|
|
|
|
uint32_t FunctionLength() const {
|
|
return (Data[0] & 0x0003ffff);
|
|
}
|
|
|
|
uint8_t Vers() const {
|
|
return (Data[0] & 0x000C0000) >> 18;
|
|
}
|
|
|
|
bool X() const {
|
|
return ((Data[0] & 0x00100000) >> 20);
|
|
}
|
|
|
|
bool E() const {
|
|
return ((Data[0] & 0x00200000) >> 21);
|
|
}
|
|
|
|
bool F() const {
|
|
return ((Data[0] & 0x00400000) >> 22);
|
|
}
|
|
|
|
uint8_t EpilogueCount() const {
|
|
if (HeaderWords(*this) == 1)
|
|
return (Data[0] & 0x0f800000) >> 23;
|
|
return Data[1] & 0x0000ffff;
|
|
}
|
|
|
|
uint8_t CodeWords() const {
|
|
if (HeaderWords(*this) == 1)
|
|
return (Data[0] & 0xf0000000) >> 28;
|
|
return (Data[1] & 0x00ff0000) >> 16;
|
|
}
|
|
|
|
ArrayRef<support::ulittle32_t> EpilogueScopes() const {
|
|
assert(E() == 0 && "epilogue scopes are only present when the E bit is 0");
|
|
size_t Offset = HeaderWords(*this);
|
|
return makeArrayRef(&Data[Offset], EpilogueCount());
|
|
}
|
|
|
|
ArrayRef<uint8_t> UnwindByteCode() const {
|
|
const size_t Offset = HeaderWords(*this)
|
|
+ (E() ? 0 : EpilogueCount());
|
|
const uint8_t *ByteCode =
|
|
reinterpret_cast<const uint8_t *>(&Data[Offset]);
|
|
return makeArrayRef(ByteCode, CodeWords() * sizeof(uint32_t));
|
|
}
|
|
|
|
uint32_t ExceptionHandlerRVA() const {
|
|
assert(X() && "Exception Handler RVA is only valid if the X bit is set");
|
|
return Data[HeaderWords(*this) + EpilogueCount() + CodeWords()];
|
|
}
|
|
|
|
uint32_t ExceptionHandlerParameter() const {
|
|
assert(X() && "Exception Handler RVA is only valid if the X bit is set");
|
|
return Data[HeaderWords(*this) + EpilogueCount() + CodeWords() + 1];
|
|
}
|
|
};
|
|
|
|
inline size_t HeaderWords(const ExceptionDataRecord &XR) {
|
|
return (XR.Data[0] & 0xff800000) ? 1 : 2;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
#endif
|