1 // Copyright 2015, VIXL authors 2 // All rights reserved. 3 // 4 // Redistribution and use in source and binary forms, with or without 5 // modification, are permitted provided that the following conditions are met: 6 // 7 // * Redistributions of source code must retain the above copyright notice, 8 // this list of conditions and the following disclaimer. 9 // * Redistributions in binary form must reproduce the above copyright notice, 10 // this list of conditions and the following disclaimer in the documentation 11 // and/or other materials provided with the distribution. 12 // * Neither the name of ARM Limited nor the names of its contributors may be 13 // used to endorse or promote products derived from this software without 14 // specific prior written permission. 15 // 16 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS CONTRIBUTORS "AS IS" AND 17 // ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 18 // WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 19 // DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE 20 // FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 // DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 22 // SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER 23 // CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 24 // OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 25 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 26 27 #ifndef VIXL_AARCH64_SIMULATOR_CONSTANTS_AARCH64_H_ 28 #define VIXL_AARCH64_SIMULATOR_CONSTANTS_AARCH64_H_ 29 30 #include "instructions-aarch64.h" 31 32 namespace vixl { 33 namespace aarch64 { 34 35 // Debug instructions. 36 // 37 // VIXL's macro-assembler and simulator support a few pseudo instructions to 38 // make debugging easier. These pseudo instructions do not exist on real 39 // hardware. 40 // 41 // TODO: Also consider allowing these pseudo-instructions to be disabled in the 42 // simulator, so that users can check that the input is a valid native code. 43 // (This isn't possible in all cases. Printf won't work, for example.) 44 // 45 // Each debug pseudo instruction is represented by a HLT instruction. The HLT 46 // immediate field is used to identify the type of debug pseudo instruction. 47 48 enum DebugHltOpcodes { 49 kUnreachableOpcode = 0xdeb0, 50 kPrintfOpcode, 51 kTraceOpcode, 52 kLogOpcode, 53 kRuntimeCallOpcode, 54 // Aliases. 55 kDebugHltFirstOpcode = kUnreachableOpcode, 56 kDebugHltLastOpcode = kLogOpcode 57 }; 58 59 // Each pseudo instruction uses a custom encoding for additional arguments, as 60 // described below. 61 62 // Unreachable - kUnreachableOpcode 63 // 64 // Instruction which should never be executed. This is used as a guard in parts 65 // of the code that should not be reachable, such as in data encoded inline in 66 // the instructions. 67 68 // Printf - kPrintfOpcode 69 // - arg_count: The number of arguments. 70 // - arg_pattern: A set of PrintfArgPattern values, packed into two-bit fields. 71 // 72 // Simulate a call to printf. 73 // 74 // Floating-point and integer arguments are passed in separate sets of registers 75 // in AAPCS64 (even for varargs functions), so it is not possible to determine 76 // the type of each argument without some information about the values that were 77 // passed in. This information could be retrieved from the printf format string, 78 // but the format string is not trivial to parse so we encode the relevant 79 // information with the HLT instruction. 80 // 81 // Also, the following registers are populated (as if for a native Aarch64 82 // call): 83 // x0: The format string 84 // x1-x7: Optional arguments, if type == CPURegister::kRegister 85 // d0-d7: Optional arguments, if type == CPURegister::kFPRegister 86 const unsigned kPrintfArgCountOffset = 1 * kInstructionSize; 87 const unsigned kPrintfArgPatternListOffset = 2 * kInstructionSize; 88 const unsigned kPrintfLength = 3 * kInstructionSize; 89 90 const unsigned kPrintfMaxArgCount = 4; 91 92 // The argument pattern is a set of two-bit-fields, each with one of the 93 // following values: 94 enum PrintfArgPattern { 95 kPrintfArgW = 1, 96 kPrintfArgX = 2, 97 // There is no kPrintfArgS because floats are always converted to doubles in C 98 // varargs calls. 99 kPrintfArgD = 3 100 }; 101 static const unsigned kPrintfArgPatternBits = 2; 102 103 // Trace - kTraceOpcode 104 // - parameter: TraceParameter stored as a uint32_t 105 // - command: TraceCommand stored as a uint32_t 106 // 107 // Allow for trace management in the generated code. This enables or disables 108 // automatic tracing of the specified information for every simulated 109 // instruction. 110 const unsigned kTraceParamsOffset = 1 * kInstructionSize; 111 const unsigned kTraceCommandOffset = 2 * kInstructionSize; 112 const unsigned kTraceLength = 3 * kInstructionSize; 113 114 // Trace parameters. 115 enum TraceParameters { 116 LOG_DISASM = 1 << 0, // Log disassembly. 117 LOG_REGS = 1 << 1, // Log general purpose registers. 118 LOG_VREGS = 1 << 2, // Log NEON and floating-point registers. 119 LOG_SYSREGS = 1 << 3, // Log the flags and system registers. 120 LOG_WRITE = 1 << 4, // Log writes to memory. 121 LOG_BRANCH = 1 << 5, // Log taken branches. 122 123 LOG_NONE = 0, 124 LOG_STATE = LOG_REGS | LOG_VREGS | LOG_SYSREGS, 125 LOG_ALL = LOG_DISASM | LOG_STATE | LOG_WRITE | LOG_BRANCH 126 }; 127 128 // Trace commands. 129 enum TraceCommand { TRACE_ENABLE = 1, TRACE_DISABLE = 2 }; 130 131 // Log - kLogOpcode 132 // - parameter: TraceParameter stored as a uint32_t 133 // 134 // Print the specified information once. This mechanism is separate from Trace. 135 // In particular, _all_ of the specified registers are printed, rather than just 136 // the registers that the instruction writes. 137 // 138 // Any combination of the TraceParameters values can be used, except that 139 // LOG_DISASM is not supported for Log. 140 const unsigned kLogParamsOffset = 1 * kInstructionSize; 141 const unsigned kLogLength = 2 * kInstructionSize; 142 143 // Runtime call simulation - kRuntimeCall 144 enum RuntimeCallType { kCallRuntime, kTailCallRuntime }; 145 146 const unsigned kRuntimeCallWrapperOffset = 1 * kInstructionSize; 147 // The size of a pointer on host. 148 const unsigned kRuntimeCallAddressSize = sizeof(uintptr_t); 149 const unsigned kRuntimeCallFunctionOffset = 150 kRuntimeCallWrapperOffset + kRuntimeCallAddressSize; 151 const unsigned kRuntimeCallTypeOffset = 152 kRuntimeCallFunctionOffset + kRuntimeCallAddressSize; 153 const unsigned kRuntimeCallLength = kRuntimeCallTypeOffset + sizeof(uint32_t); 154 } // namespace aarch64 155 } // namespace vixl 156 157 #endif // VIXL_AARCH64_SIMULATOR_CONSTANTS_AARCH64_H_ 158