1 //===-- ARMBuildAttributes.h - ARM Build Attributes -------------*- C++ -*-===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This file contains enumerations and support routines for ARM build attributes
11 // as defined in ARM ABI addenda document (ABI release 2.08).
12 //
13 // ELF for the ARM Architecture r2.09 - November 30, 2012
14 //
15 // http://infocenter.arm.com/help/topic/com.arm.doc.ihi0044e/IHI0044E_aaelf.pdf
16 //
17 //===----------------------------------------------------------------------===//
18 
19 #ifndef LLVM_SUPPORT_ARMBUILDATTRIBUTES_H
20 #define LLVM_SUPPORT_ARMBUILDATTRIBUTES_H
21 
22 namespace llvm {
23 class StringRef;
24 
25 namespace ARMBuildAttrs {
26 
27 enum SpecialAttr {
28   // This is for the .cpu asm attr. It translates into one or more
29   // AttrType (below) entries in the .ARM.attributes section in the ELF.
30   SEL_CPU
31 };
32 
33 enum AttrType {
34   // Rest correspond to ELF/.ARM.attributes
35   File                      = 1,
36   CPU_raw_name              = 4,
37   CPU_name                  = 5,
38   CPU_arch                  = 6,
39   CPU_arch_profile          = 7,
40   ARM_ISA_use               = 8,
41   THUMB_ISA_use             = 9,
42   FP_arch                   = 10,
43   WMMX_arch                 = 11,
44   Advanced_SIMD_arch        = 12,
45   PCS_config                = 13,
46   ABI_PCS_R9_use            = 14,
47   ABI_PCS_RW_data           = 15,
48   ABI_PCS_RO_data           = 16,
49   ABI_PCS_GOT_use           = 17,
50   ABI_PCS_wchar_t           = 18,
51   ABI_FP_rounding           = 19,
52   ABI_FP_denormal           = 20,
53   ABI_FP_exceptions         = 21,
54   ABI_FP_user_exceptions    = 22,
55   ABI_FP_number_model       = 23,
56   ABI_align_needed          = 24,
57   ABI_align_preserved       = 25,
58   ABI_enum_size             = 26,
59   ABI_HardFP_use            = 27,
60   ABI_VFP_args              = 28,
61   ABI_WMMX_args             = 29,
62   ABI_optimization_goals    = 30,
63   ABI_FP_optimization_goals = 31,
64   compatibility             = 32,
65   CPU_unaligned_access      = 34,
66   FP_HP_extension           = 36,
67   ABI_FP_16bit_format       = 38,
68   MPextension_use           = 42, // recoded from 70 (ABI r2.08)
69   DIV_use                   = 44,
70   also_compatible_with      = 65,
71   conformance               = 67,
72   Virtualization_use        = 68,
73 
74   /// Legacy Tags
75   Section                   = 2,  // deprecated (ABI r2.09)
76   Symbol                    = 3,  // deprecated (ABI r2.09)
77   ABI_align8_needed         = 24, // renamed to ABI_align_needed (ABI r2.09)
78   ABI_align8_preserved      = 25, // renamed to ABI_align_preserved (ABI r2.09)
79   nodefaults                = 64, // deprecated (ABI r2.09)
80   T2EE_use                  = 66, // deprecated (ABI r2.09)
81   MPextension_use_old       = 70  // recoded to MPextension_use (ABI r2.08)
82 };
83 
84 StringRef AttrTypeAsString(unsigned Attr, bool HasTagPrefix = true);
85 StringRef AttrTypeAsString(AttrType Attr, bool HasTagPrefix = true);
86 int AttrTypeFromString(StringRef Tag);
87 
88 // Magic numbers for .ARM.attributes
89 enum AttrMagic {
90   Format_Version  = 0x41
91 };
92 
93 // Legal Values for CPU_arch, (=6), uleb128
94 enum CPUArch {
95   Pre_v4   = 0,
96   v4       = 1,   // e.g. SA110
97   v4T      = 2,   // e.g. ARM7TDMI
98   v5T      = 3,   // e.g. ARM9TDMI
99   v5TE     = 4,   // e.g. ARM946E_S
100   v5TEJ    = 5,   // e.g. ARM926EJ_S
101   v6       = 6,   // e.g. ARM1136J_S
102   v6KZ     = 7,   // e.g. ARM1176JZ_S
103   v6T2     = 8,   // e.g. ARM1156T2_S
104   v6K      = 9,   // e.g. ARM1176JZ_S
105   v7       = 10,  // e.g. Cortex A8, Cortex M3
106   v6_M     = 11,  // e.g. Cortex M1
107   v6S_M    = 12,  // v6_M with the System extensions
108   v7E_M    = 13,  // v7_M with DSP extensions
109   v8       = 14,  // v8,v8.1a AArch32
110 };
111 
112 enum CPUArchProfile {               // (=7), uleb128
113   Not_Applicable          = 0,      // pre v7, or cross-profile code
114   ApplicationProfile      = (0x41), // 'A' (e.g. for Cortex A8)
115   RealTimeProfile         = (0x52), // 'R' (e.g. for Cortex R4)
116   MicroControllerProfile  = (0x4D), // 'M' (e.g. for Cortex M3)
117   SystemProfile           = (0x53)  // 'S' Application or real-time profile
118 };
119 
120 // The following have a lot of common use cases
121 enum {
122   Not_Allowed = 0,
123   Allowed = 1,
124 
125   // Tag_ARM_ISA_use (=8), uleb128
126 
127   // Tag_THUMB_ISA_use, (=9), uleb128
128   AllowThumb32 = 2, // 32-bit Thumb (implies 16-bit instructions)
129 
130   // Tag_FP_arch (=10), uleb128 (formerly Tag_VFP_arch = 10)
131   AllowFPv2  = 2,     // v2 FP ISA permitted (implies use of the v1 FP ISA)
132   AllowFPv3A = 3,     // v3 FP ISA permitted (implies use of the v2 FP ISA)
133   AllowFPv3B = 4,     // v3 FP ISA permitted, but only D0-D15, S0-S31
134   AllowFPv4A = 5,     // v4 FP ISA permitted (implies use of v3 FP ISA)
135   AllowFPv4B = 6,     // v4 FP ISA was permitted, but only D0-D15, S0-S31
136   AllowFPARMv8A = 7,  // Use of the ARM v8-A FP ISA was permitted
137   AllowFPARMv8B = 8,  // Use of the ARM v8-A FP ISA was permitted, but only
138                       // D0-D15, S0-S31
139 
140   // Tag_WMMX_arch, (=11), uleb128
141   AllowWMMXv1 = 1,  // The user permitted this entity to use WMMX v1
142   AllowWMMXv2 = 2,  // The user permitted this entity to use WMMX v2
143 
144   // Tag_Advanced_SIMD_arch, (=12), uleb128
145   AllowNeon = 1,      // SIMDv1 was permitted
146   AllowNeon2 = 2,     // SIMDv2 was permitted (Half-precision FP, MAC operations)
147   AllowNeonARMv8 = 3, // ARM v8-A SIMD was permitted
148   AllowNeonARMv8_1a = 4,// ARM v8.1-A SIMD was permitted (RDMA)
149 
150   // Tag_ABI_PCS_R9_use, (=14), uleb128
151   R9IsGPR = 0,        // R9 used as v6 (just another callee-saved register)
152   R9IsSB = 1,         // R9 used as a global static base rgister
153   R9IsTLSPointer = 2, // R9 used as a thread local storage pointer
154   R9Reserved = 3,     // R9 not used by code associated with attributed entity
155 
156   // Tag_ABI_PCS_RW_data, (=15), uleb128
157   AddressRWPCRel = 1, // Address RW static data PC-relative
158   AddressRWSBRel = 2, // Address RW static data SB-relative
159   AddressRWNone = 3, // No RW static data permitted
160 
161   // Tag_ABI_PCS_RO_data, (=14), uleb128
162   AddressROPCRel = 1, // Address RO static data PC-relative
163   AddressRONone = 2, // No RO static data permitted
164 
165   // Tag_ABI_PCS_GOT_use, (=17), uleb128
166   AddressDirect = 1, // Address imported data directly
167   AddressGOT = 2, // Address imported data indirectly (via GOT)
168 
169   // Tag_ABI_PCS_wchar_t, (=18), uleb128
170   WCharProhibited = 0,  // wchar_t is not used
171   WCharWidth2Bytes = 2, // sizeof(wchar_t) == 2
172   WCharWidth4Bytes = 4, // sizeof(wchar_t) == 4
173 
174   // Tag_ABI_FP_denormal, (=20), uleb128
175   PositiveZero = 0,
176   IEEEDenormals = 1,
177   PreserveFPSign = 2, // sign when flushed-to-zero is preserved
178 
179   // Tag_ABI_FP_number_model, (=23), uleb128
180   AllowRTABI = 2,  // numbers, infinities, and one quiet NaN (see [RTABI])
181   AllowIEE754 = 3, // this code to use all the IEEE 754-defined FP encodings
182 
183   // Tag_ABI_enum_size, (=26), uleb128
184   EnumProhibited = 0, // The user prohibited the use of enums when building
185                       // this entity.
186   EnumSmallest = 1,   // Enum is smallest container big enough to hold all
187                       // values.
188   Enum32Bit = 2,      // Enum is at least 32 bits.
189   Enum32BitABI = 3,   // Every enumeration visible across an ABI-complying
190                       // interface contains a value needing 32 bits to encode
191                       // it; other enums can be containerized.
192 
193   // Tag_ABI_HardFP_use, (=27), uleb128
194   HardFPImplied = 0,          // FP use should be implied by Tag_FP_arch
195   HardFPSinglePrecision = 1,  // Single-precision only
196 
197   // Tag_ABI_VFP_args, (=28), uleb128
198   BaseAAPCS = 0,
199   HardFPAAPCS = 1,
200 
201   // Tag_FP_HP_extension, (=36), uleb128
202   AllowHPFP = 1, // Allow use of Half Precision FP
203 
204   // Tag_FP_16bit_format, (=38), uleb128
205   FP16FormatIEEE = 1,
206 
207   // Tag_MPextension_use, (=42), uleb128
208   AllowMP = 1, // Allow use of MP extensions
209 
210   // Tag_DIV_use, (=44), uleb128
211   // Note: AllowDIVExt must be emitted if and only if the permission to use
212   // hardware divide cannot be conveyed using AllowDIVIfExists or DisallowDIV
213   AllowDIVIfExists = 0, // Allow hardware divide if available in arch, or no
214                         // info exists.
215   DisallowDIV = 1,      // Hardware divide explicitly disallowed.
216   AllowDIVExt = 2,      // Allow hardware divide as optional architecture
217                         // extension above the base arch specified by
218                         // Tag_CPU_arch and Tag_CPU_arch_profile.
219 
220   // Tag_Virtualization_use, (=68), uleb128
221   AllowTZ = 1,
222   AllowVirtualization = 2,
223   AllowTZVirtualization = 3
224 };
225 
226 } // namespace ARMBuildAttrs
227 } // namespace llvm
228 
229 #endif
230