1 //===-- X86InstrFoldTables.h - X86 Instruction Folding Tables ---*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // This file contains the interface to query the X86 memory folding tables.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #ifndef LLVM_LIB_TARGET_X86_X86INSTRFOLDTABLES_H
14 #define LLVM_LIB_TARGET_X86_X86INSTRFOLDTABLES_H
15 
16 #include <cstdint>
17 
18 namespace llvm {
19 
20 enum {
21   // Select which memory operand is being unfolded.
22   // (stored in bits 0 - 2)
23   TB_INDEX_0    = 0,
24   TB_INDEX_1    = 1,
25   TB_INDEX_2    = 2,
26   TB_INDEX_3    = 3,
27   TB_INDEX_4    = 4,
28   TB_INDEX_MASK = 0x7,
29 
30   // Do not insert the reverse map (MemOp -> RegOp) into the table.
31   // This may be needed because there is a many -> one mapping.
32   TB_NO_REVERSE   = 1 << 3,
33 
34   // Do not insert the forward map (RegOp -> MemOp) into the table.
35   // This is needed for Native Client, which prohibits branch
36   // instructions from using a memory operand.
37   TB_NO_FORWARD   = 1 << 4,
38 
39   TB_FOLDED_LOAD  = 1 << 5,
40   TB_FOLDED_STORE = 1 << 6,
41   TB_FOLDED_BCAST = 1 << 7,
42 
43   // Minimum alignment required for load/store.
44   // Used for RegOp->MemOp conversion. Encoded as Log2(Align) + 1 to allow 0
45   // to mean align of 0.
46   // (stored in bits 8 - 11)
47   TB_ALIGN_SHIFT = 8,
48   TB_ALIGN_NONE  =   0 << TB_ALIGN_SHIFT,
49   TB_ALIGN_16    =   5 << TB_ALIGN_SHIFT,
50   TB_ALIGN_32    =   6 << TB_ALIGN_SHIFT,
51   TB_ALIGN_64    =   7 << TB_ALIGN_SHIFT,
52   TB_ALIGN_MASK  = 0xf << TB_ALIGN_SHIFT,
53 
54   // Broadcast type.
55   // (stored in bits 12 - 13)
56   TB_BCAST_TYPE_SHIFT = 12,
57   TB_BCAST_D    =   0 << TB_BCAST_TYPE_SHIFT,
58   TB_BCAST_Q    =   1 << TB_BCAST_TYPE_SHIFT,
59   TB_BCAST_SS   =   2 << TB_BCAST_TYPE_SHIFT,
60   TB_BCAST_SD   =   3 << TB_BCAST_TYPE_SHIFT,
61   TB_BCAST_MASK = 0x3 << TB_BCAST_TYPE_SHIFT,
62 
63   // Unused bits 14-15
64 };
65 
66 // This struct is used for both the folding and unfold tables. They KeyOp
67 // is used to determine the sorting order.
68 struct X86MemoryFoldTableEntry {
69   uint16_t KeyOp;
70   uint16_t DstOp;
71   uint16_t Flags;
72 
73   bool operator<(const X86MemoryFoldTableEntry &RHS) const {
74     return KeyOp < RHS.KeyOp;
75   }
76   bool operator==(const X86MemoryFoldTableEntry &RHS) const {
77     return KeyOp == RHS.KeyOp;
78   }
79   friend bool operator<(const X86MemoryFoldTableEntry &TE, unsigned Opcode) {
80     return TE.KeyOp < Opcode;
81   }
82 };
83 
84 // Look up the memory folding table entry for folding a load and a store into
85 // operand 0.
86 const X86MemoryFoldTableEntry *lookupTwoAddrFoldTable(unsigned RegOp);
87 
88 // Look up the memory folding table entry for folding a load or store with
89 // operand OpNum.
90 const X86MemoryFoldTableEntry *lookupFoldTable(unsigned RegOp, unsigned OpNum);
91 
92 // Look up the memory unfolding table entry for this instruction.
93 const X86MemoryFoldTableEntry *lookupUnfoldTable(unsigned MemOp);
94 
95 } // namespace llvm
96 
97 #endif
98