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1//===-- X86InstrExtension.td - Sign and Zero Extensions ----*- tablegen -*-===//
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 describes the sign and zero extension operations.
11//
12//===----------------------------------------------------------------------===//
13
14let neverHasSideEffects = 1 in {
15  let Defs = [AX], Uses = [AL] in
16  def CBW : I<0x98, RawFrm, (outs), (ins),
17              "{cbtw|cbw}", []>, OpSize;   // AX = signext(AL)
18  let Defs = [EAX], Uses = [AX] in
19  def CWDE : I<0x98, RawFrm, (outs), (ins),
20              "{cwtl|cwde}", []>;   // EAX = signext(AX)
21
22  let Defs = [AX,DX], Uses = [AX] in
23  def CWD : I<0x99, RawFrm, (outs), (ins),
24              "{cwtd|cwd}", []>, OpSize; // DX:AX = signext(AX)
25  let Defs = [EAX,EDX], Uses = [EAX] in
26  def CDQ : I<0x99, RawFrm, (outs), (ins),
27              "{cltd|cdq}", []>; // EDX:EAX = signext(EAX)
28
29
30  let Defs = [RAX], Uses = [EAX] in
31  def CDQE : RI<0x98, RawFrm, (outs), (ins),
32               "{cltq|cdqe}", []>;     // RAX = signext(EAX)
33
34  let Defs = [RAX,RDX], Uses = [RAX] in
35  def CQO  : RI<0x99, RawFrm, (outs), (ins),
36                "{cqto|cqo}", []>; // RDX:RAX = signext(RAX)
37}
38
39
40
41// Sign/Zero extenders
42let neverHasSideEffects = 1 in {
43def MOVSX16rr8 : I<0xBE, MRMSrcReg, (outs GR16:$dst), (ins GR8:$src),
44                   "movs{bw|x}\t{$src, $dst|$dst, $src}", [], IIC_MOVSX_R16_R8>,
45                   TB, OpSize;
46let mayLoad = 1 in
47def MOVSX16rm8 : I<0xBE, MRMSrcMem, (outs GR16:$dst), (ins i8mem:$src),
48                   "movs{bw|x}\t{$src, $dst|$dst, $src}", [], IIC_MOVSX_R16_M8>,
49                   TB, OpSize;
50} // neverHasSideEffects = 1
51def MOVSX32rr8 : I<0xBE, MRMSrcReg, (outs GR32:$dst), (ins GR8:$src),
52                   "movs{bl|x}\t{$src, $dst|$dst, $src}",
53                   [(set GR32:$dst, (sext GR8:$src))], IIC_MOVSX>, TB;
54def MOVSX32rm8 : I<0xBE, MRMSrcMem, (outs GR32:$dst), (ins i8mem :$src),
55                   "movs{bl|x}\t{$src, $dst|$dst, $src}",
56                   [(set GR32:$dst, (sextloadi32i8 addr:$src))], IIC_MOVSX>, TB;
57def MOVSX32rr16: I<0xBF, MRMSrcReg, (outs GR32:$dst), (ins GR16:$src),
58                   "movs{wl|x}\t{$src, $dst|$dst, $src}",
59                   [(set GR32:$dst, (sext GR16:$src))], IIC_MOVSX>, TB;
60def MOVSX32rm16: I<0xBF, MRMSrcMem, (outs GR32:$dst), (ins i16mem:$src),
61                   "movs{wl|x}\t{$src, $dst|$dst, $src}",
62                   [(set GR32:$dst, (sextloadi32i16 addr:$src))], IIC_MOVSX>,
63                   TB;
64
65let neverHasSideEffects = 1 in {
66def MOVZX16rr8 : I<0xB6, MRMSrcReg, (outs GR16:$dst), (ins GR8:$src),
67                   "movz{bw|x}\t{$src, $dst|$dst, $src}", [], IIC_MOVZX_R16_R8>,
68                   TB, OpSize;
69let mayLoad = 1 in
70def MOVZX16rm8 : I<0xB6, MRMSrcMem, (outs GR16:$dst), (ins i8mem:$src),
71                   "movz{bw|x}\t{$src, $dst|$dst, $src}", [], IIC_MOVZX_R16_M8>,
72                   TB, OpSize;
73} // neverHasSideEffects = 1
74def MOVZX32rr8 : I<0xB6, MRMSrcReg, (outs GR32:$dst), (ins GR8 :$src),
75                   "movz{bl|x}\t{$src, $dst|$dst, $src}",
76                   [(set GR32:$dst, (zext GR8:$src))], IIC_MOVZX>, TB;
77def MOVZX32rm8 : I<0xB6, MRMSrcMem, (outs GR32:$dst), (ins i8mem :$src),
78                   "movz{bl|x}\t{$src, $dst|$dst, $src}",
79                   [(set GR32:$dst, (zextloadi32i8 addr:$src))], IIC_MOVZX>, TB;
80def MOVZX32rr16: I<0xB7, MRMSrcReg, (outs GR32:$dst), (ins GR16:$src),
81                   "movz{wl|x}\t{$src, $dst|$dst, $src}",
82                   [(set GR32:$dst, (zext GR16:$src))], IIC_MOVZX>, TB;
83def MOVZX32rm16: I<0xB7, MRMSrcMem, (outs GR32:$dst), (ins i16mem:$src),
84                   "movz{wl|x}\t{$src, $dst|$dst, $src}",
85                   [(set GR32:$dst, (zextloadi32i16 addr:$src))], IIC_MOVZX>,
86                   TB;
87
88// These are the same as the regular MOVZX32rr8 and MOVZX32rm8
89// except that they use GR32_NOREX for the output operand register class
90// instead of GR32. This allows them to operate on h registers on x86-64.
91let neverHasSideEffects = 1, isCodeGenOnly = 1 in {
92def MOVZX32_NOREXrr8 : I<0xB6, MRMSrcReg,
93                         (outs GR32_NOREX:$dst), (ins GR8_NOREX:$src),
94                         "movz{bl|x}\t{$src, $dst|$dst, $src}",
95                         [], IIC_MOVZX>, TB;
96let mayLoad = 1 in
97def MOVZX32_NOREXrm8 : I<0xB6, MRMSrcMem,
98                         (outs GR32_NOREX:$dst), (ins i8mem_NOREX:$src),
99                         "movz{bl|x}\t{$src, $dst|$dst, $src}",
100                         [], IIC_MOVZX>, TB;
101}
102
103// MOVSX64rr8 always has a REX prefix and it has an 8-bit register
104// operand, which makes it a rare instruction with an 8-bit register
105// operand that can never access an h register. If support for h registers
106// were generalized, this would require a special register class.
107def MOVSX64rr8 : RI<0xBE, MRMSrcReg, (outs GR64:$dst), (ins GR8 :$src),
108                    "movs{bq|x}\t{$src, $dst|$dst, $src}",
109                    [(set GR64:$dst, (sext GR8:$src))], IIC_MOVSX>, TB;
110def MOVSX64rm8 : RI<0xBE, MRMSrcMem, (outs GR64:$dst), (ins i8mem :$src),
111                    "movs{bq|x}\t{$src, $dst|$dst, $src}",
112                    [(set GR64:$dst, (sextloadi64i8 addr:$src))], IIC_MOVSX>,
113                    TB;
114def MOVSX64rr16: RI<0xBF, MRMSrcReg, (outs GR64:$dst), (ins GR16:$src),
115                    "movs{wq|x}\t{$src, $dst|$dst, $src}",
116                    [(set GR64:$dst, (sext GR16:$src))], IIC_MOVSX>, TB;
117def MOVSX64rm16: RI<0xBF, MRMSrcMem, (outs GR64:$dst), (ins i16mem:$src),
118                    "movs{wq|x}\t{$src, $dst|$dst, $src}",
119                    [(set GR64:$dst, (sextloadi64i16 addr:$src))], IIC_MOVSX>,
120                    TB;
121def MOVSX64rr32: RI<0x63, MRMSrcReg, (outs GR64:$dst), (ins GR32:$src),
122                    "movs{lq|xd}\t{$src, $dst|$dst, $src}",
123                    [(set GR64:$dst, (sext GR32:$src))], IIC_MOVSX>;
124def MOVSX64rm32: RI<0x63, MRMSrcMem, (outs GR64:$dst), (ins i32mem:$src),
125                    "movs{lq|xd}\t{$src, $dst|$dst, $src}",
126                    [(set GR64:$dst, (sextloadi64i32 addr:$src))], IIC_MOVSX>;
127
128// movzbq and movzwq encodings for the disassembler
129def MOVZX64rr8_Q : RI<0xB6, MRMSrcReg, (outs GR64:$dst), (ins GR8:$src),
130                       "movz{bq|x}\t{$src, $dst|$dst, $src}", [], IIC_MOVZX>,
131                       TB;
132def MOVZX64rm8_Q : RI<0xB6, MRMSrcMem, (outs GR64:$dst), (ins i8mem:$src),
133                       "movz{bq|x}\t{$src, $dst|$dst, $src}", [], IIC_MOVZX>,
134                       TB;
135def MOVZX64rr16_Q : RI<0xB7, MRMSrcReg, (outs GR64:$dst), (ins GR16:$src),
136                       "movz{wq|x}\t{$src, $dst|$dst, $src}", [], IIC_MOVZX>,
137                       TB;
138def MOVZX64rm16_Q : RI<0xB7, MRMSrcMem, (outs GR64:$dst), (ins i16mem:$src),
139                       "movz{wq|x}\t{$src, $dst|$dst, $src}", [], IIC_MOVZX>,
140                       TB;
141
142// FIXME: These should be Pat patterns.
143let isCodeGenOnly = 1 in {
144
145// Use movzbl instead of movzbq when the destination is a register; it's
146// equivalent due to implicit zero-extending, and it has a smaller encoding.
147def MOVZX64rr8 : I<0xB6, MRMSrcReg, (outs GR64:$dst), (ins GR8 :$src),
148                   "", [(set GR64:$dst, (zext GR8:$src))], IIC_MOVZX>, TB;
149def MOVZX64rm8 : I<0xB6, MRMSrcMem, (outs GR64:$dst), (ins i8mem :$src),
150                   "", [(set GR64:$dst, (zextloadi64i8 addr:$src))], IIC_MOVZX>,
151                   TB;
152// Use movzwl instead of movzwq when the destination is a register; it's
153// equivalent due to implicit zero-extending, and it has a smaller encoding.
154def MOVZX64rr16: I<0xB7, MRMSrcReg, (outs GR64:$dst), (ins GR16:$src),
155                   "", [(set GR64:$dst, (zext GR16:$src))], IIC_MOVZX>, TB;
156def MOVZX64rm16: I<0xB7, MRMSrcMem, (outs GR64:$dst), (ins i16mem:$src),
157                   "", [(set GR64:$dst, (zextloadi64i16 addr:$src))],
158                   IIC_MOVZX>, TB;
159
160// There's no movzlq instruction, but movl can be used for this purpose, using
161// implicit zero-extension. The preferred way to do 32-bit-to-64-bit zero
162// extension on x86-64 is to use a SUBREG_TO_REG to utilize implicit
163// zero-extension, however this isn't possible when the 32-bit value is
164// defined by a truncate or is copied from something where the high bits aren't
165// necessarily all zero. In such cases, we fall back to these explicit zext
166// instructions.
167def MOVZX64rr32 : I<0x89, MRMDestReg, (outs GR64:$dst), (ins GR32:$src),
168                    "", [(set GR64:$dst, (zext GR32:$src))], IIC_MOVZX>;
169def MOVZX64rm32 : I<0x8B, MRMSrcMem, (outs GR64:$dst), (ins i32mem:$src),
170                    "", [(set GR64:$dst, (zextloadi64i32 addr:$src))],
171                    IIC_MOVZX>;
172}
173
174