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 DebugHltOpcode { 49 kUnreachableOpcode = 0xdeb0, 50 kPrintfOpcode, 51 kTraceOpcode, 52 kLogOpcode, 53 kRuntimeCallOpcode, 54 kSetCPUFeaturesOpcode, 55 kEnableCPUFeaturesOpcode, 56 kDisableCPUFeaturesOpcode, 57 kSaveCPUFeaturesOpcode, 58 kRestoreCPUFeaturesOpcode, 59 // Aliases. 60 kDebugHltFirstOpcode = kUnreachableOpcode, 61 kDebugHltLastOpcode = kLogOpcode 62 }; 63 VIXL_DEPRECATED("DebugHltOpcode", typedef DebugHltOpcode DebugHltOpcodes); 64 65 // Each pseudo instruction uses a custom encoding for additional arguments, as 66 // described below. 67 68 // Unreachable - kUnreachableOpcode 69 // 70 // Instruction which should never be executed. This is used as a guard in parts 71 // of the code that should not be reachable, such as in data encoded inline in 72 // the instructions. 73 74 // Printf - kPrintfOpcode 75 // - arg_count: The number of arguments. 76 // - arg_pattern: A set of PrintfArgPattern values, packed into two-bit fields. 77 // 78 // Simulate a call to printf. 79 // 80 // Floating-point and integer arguments are passed in separate sets of registers 81 // in AAPCS64 (even for varargs functions), so it is not possible to determine 82 // the type of each argument without some information about the values that were 83 // passed in. This information could be retrieved from the printf format string, 84 // but the format string is not trivial to parse so we encode the relevant 85 // information with the HLT instruction. 86 // 87 // Also, the following registers are populated (as if for a native Aarch64 88 // call): 89 // x0: The format string 90 // x1-x7: Optional arguments, if type == CPURegister::kRegister 91 // d0-d7: Optional arguments, if type == CPURegister::kFPRegister 92 const unsigned kPrintfArgCountOffset = 1 * kInstructionSize; 93 const unsigned kPrintfArgPatternListOffset = 2 * kInstructionSize; 94 const unsigned kPrintfLength = 3 * kInstructionSize; 95 96 const unsigned kPrintfMaxArgCount = 4; 97 98 // The argument pattern is a set of two-bit-fields, each with one of the 99 // following values: 100 enum PrintfArgPattern { 101 kPrintfArgW = 1, 102 kPrintfArgX = 2, 103 // There is no kPrintfArgS because floats are always converted to doubles in C 104 // varargs calls. 105 kPrintfArgD = 3 106 }; 107 static const unsigned kPrintfArgPatternBits = 2; 108 109 // Trace - kTraceOpcode 110 // - parameter: TraceParameter stored as a uint32_t 111 // - command: TraceCommand stored as a uint32_t 112 // 113 // Allow for trace management in the generated code. This enables or disables 114 // automatic tracing of the specified information for every simulated 115 // instruction. 116 const unsigned kTraceParamsOffset = 1 * kInstructionSize; 117 const unsigned kTraceCommandOffset = 2 * kInstructionSize; 118 const unsigned kTraceLength = 3 * kInstructionSize; 119 120 // Trace parameters. 121 enum TraceParameters { 122 LOG_DISASM = 1 << 0, // Log disassembly. 123 LOG_REGS = 1 << 1, // Log general purpose registers. 124 LOG_VREGS = 1 << 2, // Log NEON and floating-point registers. 125 LOG_SYSREGS = 1 << 3, // Log the flags and system registers. 126 LOG_WRITE = 1 << 4, // Log writes to memory. 127 LOG_BRANCH = 1 << 5, // Log taken branches. 128 129 LOG_NONE = 0, 130 LOG_STATE = LOG_REGS | LOG_VREGS | LOG_SYSREGS, 131 LOG_ALL = LOG_DISASM | LOG_STATE | LOG_WRITE | LOG_BRANCH 132 }; 133 134 // Trace commands. 135 enum TraceCommand { TRACE_ENABLE = 1, TRACE_DISABLE = 2 }; 136 137 // Log - kLogOpcode 138 // - parameter: TraceParameter stored as a uint32_t 139 // 140 // Print the specified information once. This mechanism is separate from Trace. 141 // In particular, _all_ of the specified registers are printed, rather than just 142 // the registers that the instruction writes. 143 // 144 // Any combination of the TraceParameters values can be used, except that 145 // LOG_DISASM is not supported for Log. 146 const unsigned kLogParamsOffset = 1 * kInstructionSize; 147 const unsigned kLogLength = 2 * kInstructionSize; 148 149 // Runtime call simulation - kRuntimeCallOpcode 150 enum RuntimeCallType { kCallRuntime, kTailCallRuntime }; 151 152 const unsigned kRuntimeCallWrapperOffset = 1 * kInstructionSize; 153 // The size of a pointer on host. 154 const unsigned kRuntimeCallAddressSize = sizeof(uintptr_t); 155 const unsigned kRuntimeCallFunctionOffset = 156 kRuntimeCallWrapperOffset + kRuntimeCallAddressSize; 157 const unsigned kRuntimeCallTypeOffset = 158 kRuntimeCallFunctionOffset + kRuntimeCallAddressSize; 159 const unsigned kRuntimeCallLength = kRuntimeCallTypeOffset + sizeof(uint32_t); 160 161 // Enable or disable CPU features - kSetCPUFeaturesOpcode 162 // - kEnableCPUFeaturesOpcode 163 // - kDisableCPUFeaturesOpcode 164 // - parameter[...]: A list of `CPUFeatures::Feature`s, encoded as 165 // ConfigureCPUFeaturesElementType and terminated with CPUFeatures::kNone. 166 // - [Padding to align to kInstructionSize.] 167 // 168 // 'Set' completely overwrites the existing CPU features. 169 // 'Enable' and 'Disable' update the existing CPU features. 170 // 171 // These mechanisms allows users to strictly check the use of CPU features in 172 // different regions of code. 173 // 174 // These have no effect on the set of 'seen' features (as reported by 175 // CPUFeaturesAuditor::HasSeen(...)). 176 typedef uint8_t ConfigureCPUFeaturesElementType; 177 const unsigned kConfigureCPUFeaturesListOffset = 1 * kInstructionSize; 178 179 // Save or restore CPU features - kSaveCPUFeaturesOpcode 180 // - kRestoreCPUFeaturesOpcode 181 // 182 // These mechanisms provide a stack-like mechanism for preserving the CPU 183 // features, or restoring the last-preserved features. These pseudo-instructions 184 // take no arguments. 185 // 186 // These have no effect on the set of 'seen' features (as reported by 187 // CPUFeaturesAuditor::HasSeen(...)). 188 189 } // namespace aarch64 190 } // namespace vixl 191 192 #endif // VIXL_AARCH64_SIMULATOR_CONSTANTS_AARCH64_H_ 193