1 // Copyright 2009 the V8 project authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4 
5 #include "src/v8.h"
6 
7 #if V8_TARGET_ARCH_ARM
8 
9 #include "src/arm/constants-arm.h"
10 
11 
12 namespace v8 {
13 namespace internal {
14 
DoubleImmedVmov() const15 double Instruction::DoubleImmedVmov() const {
16   // Reconstruct a double from the immediate encoded in the vmov instruction.
17   //
18   //   instruction: [xxxxxxxx,xxxxabcd,xxxxxxxx,xxxxefgh]
19   //   double: [aBbbbbbb,bbcdefgh,00000000,00000000,
20   //            00000000,00000000,00000000,00000000]
21   //
22   // where B = ~b. Only the high 16 bits are affected.
23   uint64_t high16;
24   high16  = (Bits(17, 16) << 4) | Bits(3, 0);   // xxxxxxxx,xxcdefgh.
25   high16 |= (0xff * Bit(18)) << 6;              // xxbbbbbb,bbxxxxxx.
26   high16 |= (Bit(18) ^ 1) << 14;                // xBxxxxxx,xxxxxxxx.
27   high16 |= Bit(19) << 15;                      // axxxxxxx,xxxxxxxx.
28 
29   uint64_t imm = high16 << 48;
30   double d;
31   memcpy(&d, &imm, 8);
32   return d;
33 }
34 
35 
36 // These register names are defined in a way to match the native disassembler
37 // formatting. See for example the command "objdump -d <binary file>".
38 const char* Registers::names_[kNumRegisters] = {
39   "r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7",
40   "r8", "r9", "r10", "fp", "ip", "sp", "lr", "pc",
41 };
42 
43 
44 // List of alias names which can be used when referring to ARM registers.
45 const Registers::RegisterAlias Registers::aliases_[] = {
46   {10, "sl"},
47   {11, "r11"},
48   {12, "r12"},
49   {13, "r13"},
50   {14, "r14"},
51   {15, "r15"},
52   {kNoRegister, NULL}
53 };
54 
55 
Name(int reg)56 const char* Registers::Name(int reg) {
57   const char* result;
58   if ((0 <= reg) && (reg < kNumRegisters)) {
59     result = names_[reg];
60   } else {
61     result = "noreg";
62   }
63   return result;
64 }
65 
66 
67 // Support for VFP registers s0 to s31 (d0 to d15) and d16-d31.
68 // Note that "sN:sM" is the same as "dN/2" up to d15.
69 // These register names are defined in a way to match the native disassembler
70 // formatting. See for example the command "objdump -d <binary file>".
71 const char* VFPRegisters::names_[kNumVFPRegisters] = {
72     "s0", "s1", "s2", "s3", "s4", "s5", "s6", "s7",
73     "s8", "s9", "s10", "s11", "s12", "s13", "s14", "s15",
74     "s16", "s17", "s18", "s19", "s20", "s21", "s22", "s23",
75     "s24", "s25", "s26", "s27", "s28", "s29", "s30", "s31",
76     "d0", "d1", "d2", "d3", "d4", "d5", "d6", "d7",
77     "d8", "d9", "d10", "d11", "d12", "d13", "d14", "d15",
78     "d16", "d17", "d18", "d19", "d20", "d21", "d22", "d23",
79     "d24", "d25", "d26", "d27", "d28", "d29", "d30", "d31"
80 };
81 
82 
Name(int reg,bool is_double)83 const char* VFPRegisters::Name(int reg, bool is_double) {
84   DCHECK((0 <= reg) && (reg < kNumVFPRegisters));
85   return names_[reg + (is_double ? kNumVFPSingleRegisters : 0)];
86 }
87 
88 
Number(const char * name,bool * is_double)89 int VFPRegisters::Number(const char* name, bool* is_double) {
90   for (int i = 0; i < kNumVFPRegisters; i++) {
91     if (strcmp(names_[i], name) == 0) {
92       if (i < kNumVFPSingleRegisters) {
93         *is_double = false;
94         return i;
95       } else {
96         *is_double = true;
97         return i - kNumVFPSingleRegisters;
98       }
99     }
100   }
101 
102   // No register with the requested name found.
103   return kNoRegister;
104 }
105 
106 
Number(const char * name)107 int Registers::Number(const char* name) {
108   // Look through the canonical names.
109   for (int i = 0; i < kNumRegisters; i++) {
110     if (strcmp(names_[i], name) == 0) {
111       return i;
112     }
113   }
114 
115   // Look through the alias names.
116   int i = 0;
117   while (aliases_[i].reg != kNoRegister) {
118     if (strcmp(aliases_[i].name, name) == 0) {
119       return aliases_[i].reg;
120     }
121     i++;
122   }
123 
124   // No register with the requested name found.
125   return kNoRegister;
126 }
127 
128 
129 } }  // namespace v8::internal
130 
131 #endif  // V8_TARGET_ARCH_ARM
132