1 //===-- X86InstrExtension.td - Sign and Zero Extensions ----*- tablegen -*-===//
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
7 //===----------------------------------------------------------------------===//
9 // This file describes the sign and zero extension operations.
11 //===----------------------------------------------------------------------===//
13 let hasSideEffects = 0 in {
14 let Defs = [AX], Uses = [AL] in // AX = signext(AL)
15 def CBW : I<0x98, RawFrm, (outs), (ins),
16 "{cbtw|cbw}", []>, OpSize16, Sched<[WriteALU]>;
17 let Defs = [EAX], Uses = [AX] in // EAX = signext(AX)
18 def CWDE : I<0x98, RawFrm, (outs), (ins),
19 "{cwtl|cwde}", []>, OpSize32, Sched<[WriteALU]>;
21 let Defs = [AX,DX], Uses = [AX] in // DX:AX = signext(AX)
22 def CWD : I<0x99, RawFrm, (outs), (ins),
23 "{cwtd|cwd}", []>, OpSize16, Sched<[WriteALU]>;
24 let Defs = [EAX,EDX], Uses = [EAX] in // EDX:EAX = signext(EAX)
25 def CDQ : I<0x99, RawFrm, (outs), (ins),
26 "{cltd|cdq}", []>, OpSize32, Sched<[WriteALU]>;
29 let Defs = [RAX], Uses = [EAX] in // RAX = signext(EAX)
30 def CDQE : RI<0x98, RawFrm, (outs), (ins),
31 "{cltq|cdqe}", []>, Sched<[WriteALU]>, Requires<[In64BitMode]>;
33 let Defs = [RAX,RDX], Uses = [RAX] in // RDX:RAX = signext(RAX)
34 def CQO : RI<0x99, RawFrm, (outs), (ins),
35 "{cqto|cqo}", []>, Sched<[WriteALU]>, Requires<[In64BitMode]>;
38 // Sign/Zero extenders
39 let hasSideEffects = 0 in {
40 def MOVSX16rr8 : I<0xBE, MRMSrcReg, (outs GR16:$dst), (ins GR8:$src),
41 "movs{bw|x}\t{$src, $dst|$dst, $src}", []>,
42 TB, OpSize16, Sched<[WriteALU]>;
44 def MOVSX16rm8 : I<0xBE, MRMSrcMem, (outs GR16:$dst), (ins i8mem:$src),
45 "movs{bw|x}\t{$src, $dst|$dst, $src}", []>,
46 TB, OpSize16, Sched<[WriteALULd]>;
47 } // hasSideEffects = 0
48 def MOVSX32rr8 : I<0xBE, MRMSrcReg, (outs GR32:$dst), (ins GR8:$src),
49 "movs{bl|x}\t{$src, $dst|$dst, $src}",
50 [(set GR32:$dst, (sext GR8:$src))]>, TB,
51 OpSize32, Sched<[WriteALU]>;
52 def MOVSX32rm8 : I<0xBE, MRMSrcMem, (outs GR32:$dst), (ins i8mem :$src),
53 "movs{bl|x}\t{$src, $dst|$dst, $src}",
54 [(set GR32:$dst, (sextloadi32i8 addr:$src))]>, TB,
55 OpSize32, Sched<[WriteALULd]>;
56 def MOVSX32rr16: I<0xBF, MRMSrcReg, (outs GR32:$dst), (ins GR16:$src),
57 "movs{wl|x}\t{$src, $dst|$dst, $src}",
58 [(set GR32:$dst, (sext GR16:$src))]>, TB,
59 OpSize32, Sched<[WriteALU]>;
60 def MOVSX32rm16: I<0xBF, MRMSrcMem, (outs GR32:$dst), (ins i16mem:$src),
61 "movs{wl|x}\t{$src, $dst|$dst, $src}",
62 [(set GR32:$dst, (sextloadi32i16 addr:$src))]>,
63 OpSize32, TB, Sched<[WriteALULd]>;
65 let hasSideEffects = 0 in {
66 def MOVZX16rr8 : I<0xB6, MRMSrcReg, (outs GR16:$dst), (ins GR8:$src),
67 "movz{bw|x}\t{$src, $dst|$dst, $src}", []>,
68 TB, OpSize16, Sched<[WriteALU]>;
70 def MOVZX16rm8 : I<0xB6, MRMSrcMem, (outs GR16:$dst), (ins i8mem:$src),
71 "movz{bw|x}\t{$src, $dst|$dst, $src}", []>,
72 TB, OpSize16, Sched<[WriteALULd]>;
73 } // hasSideEffects = 0
74 def MOVZX32rr8 : I<0xB6, MRMSrcReg, (outs GR32:$dst), (ins GR8 :$src),
75 "movz{bl|x}\t{$src, $dst|$dst, $src}",
76 [(set GR32:$dst, (zext GR8:$src))]>, TB,
77 OpSize32, Sched<[WriteALU]>;
78 def MOVZX32rm8 : I<0xB6, MRMSrcMem, (outs GR32:$dst), (ins i8mem :$src),
79 "movz{bl|x}\t{$src, $dst|$dst, $src}",
80 [(set GR32:$dst, (zextloadi32i8 addr:$src))]>, TB,
81 OpSize32, Sched<[WriteALULd]>;
82 def MOVZX32rr16: I<0xB7, MRMSrcReg, (outs GR32:$dst), (ins GR16:$src),
83 "movz{wl|x}\t{$src, $dst|$dst, $src}",
84 [(set GR32:$dst, (zext GR16:$src))]>, TB,
85 OpSize32, Sched<[WriteALU]>;
86 def MOVZX32rm16: I<0xB7, MRMSrcMem, (outs GR32:$dst), (ins i16mem:$src),
87 "movz{wl|x}\t{$src, $dst|$dst, $src}",
88 [(set GR32:$dst, (zextloadi32i16 addr:$src))]>,
89 TB, OpSize32, Sched<[WriteALULd]>;
91 // These instructions exist as a consequence of operand size prefix having
92 // control of the destination size, but not the input size. Only support them
93 // for the disassembler.
94 let isCodeGenOnly = 1, ForceDisassemble = 1, hasSideEffects = 0 in {
95 def MOVSX16rr16: I<0xBF, MRMSrcReg, (outs GR16:$dst), (ins GR16:$src),
96 "movs{ww|x}\t{$src, $dst|$dst, $src}",
97 []>, TB, OpSize16, Sched<[WriteALU]>, NotMemoryFoldable;
98 def MOVZX16rr16: I<0xB7, MRMSrcReg, (outs GR16:$dst), (ins GR16:$src),
99 "movz{ww|x}\t{$src, $dst|$dst, $src}",
100 []>, TB, OpSize16, Sched<[WriteALU]>, NotMemoryFoldable;
102 def MOVSX16rm16: I<0xBF, MRMSrcMem, (outs GR16:$dst), (ins i16mem:$src),
103 "movs{ww|x}\t{$src, $dst|$dst, $src}",
104 []>, OpSize16, TB, Sched<[WriteALULd]>, NotMemoryFoldable;
105 def MOVZX16rm16: I<0xB7, MRMSrcMem, (outs GR16:$dst), (ins i16mem:$src),
106 "movz{ww|x}\t{$src, $dst|$dst, $src}",
107 []>, TB, OpSize16, Sched<[WriteALULd]>, NotMemoryFoldable;
109 } // isCodeGenOnly = 1, ForceDisassemble = 1, hasSideEffects = 0
111 // These are the same as the regular MOVZX32rr8 and MOVZX32rm8
112 // except that they use GR32_NOREX for the output operand register class
113 // instead of GR32. This allows them to operate on h registers on x86-64.
114 let hasSideEffects = 0, isCodeGenOnly = 1 in {
115 def MOVZX32rr8_NOREX : I<0xB6, MRMSrcReg,
116 (outs GR32_NOREX:$dst), (ins GR8_NOREX:$src),
117 "movz{bl|x}\t{$src, $dst|$dst, $src}",
118 []>, TB, OpSize32, Sched<[WriteALU]>;
120 def MOVZX32rm8_NOREX : I<0xB6, MRMSrcMem,
121 (outs GR32_NOREX:$dst), (ins i8mem_NOREX:$src),
122 "movz{bl|x}\t{$src, $dst|$dst, $src}",
123 []>, TB, OpSize32, Sched<[WriteALULd]>;
125 def MOVSX32rr8_NOREX : I<0xBE, MRMSrcReg,
126 (outs GR32_NOREX:$dst), (ins GR8_NOREX:$src),
127 "movs{bl|x}\t{$src, $dst|$dst, $src}",
128 []>, TB, OpSize32, Sched<[WriteALU]>;
130 def MOVSX32rm8_NOREX : I<0xBE, MRMSrcMem,
131 (outs GR32_NOREX:$dst), (ins i8mem_NOREX:$src),
132 "movs{bl|x}\t{$src, $dst|$dst, $src}",
133 []>, TB, OpSize32, Sched<[WriteALULd]>;
136 // MOVSX64rr8 always has a REX prefix and it has an 8-bit register
137 // operand, which makes it a rare instruction with an 8-bit register
138 // operand that can never access an h register. If support for h registers
139 // were generalized, this would require a special register class.
140 def MOVSX64rr8 : RI<0xBE, MRMSrcReg, (outs GR64:$dst), (ins GR8 :$src),
141 "movs{bq|x}\t{$src, $dst|$dst, $src}",
142 [(set GR64:$dst, (sext GR8:$src))]>, TB,
144 def MOVSX64rm8 : RI<0xBE, MRMSrcMem, (outs GR64:$dst), (ins i8mem :$src),
145 "movs{bq|x}\t{$src, $dst|$dst, $src}",
146 [(set GR64:$dst, (sextloadi64i8 addr:$src))]>,
147 TB, Sched<[WriteALULd]>;
148 def MOVSX64rr16: RI<0xBF, MRMSrcReg, (outs GR64:$dst), (ins GR16:$src),
149 "movs{wq|x}\t{$src, $dst|$dst, $src}",
150 [(set GR64:$dst, (sext GR16:$src))]>, TB,
152 def MOVSX64rm16: RI<0xBF, MRMSrcMem, (outs GR64:$dst), (ins i16mem:$src),
153 "movs{wq|x}\t{$src, $dst|$dst, $src}",
154 [(set GR64:$dst, (sextloadi64i16 addr:$src))]>,
155 TB, Sched<[WriteALULd]>;
156 def MOVSX64rr32: RI<0x63, MRMSrcReg, (outs GR64:$dst), (ins GR32:$src),
157 "movs{lq|xd}\t{$src, $dst|$dst, $src}",
158 [(set GR64:$dst, (sext GR32:$src))]>,
159 Sched<[WriteALU]>, Requires<[In64BitMode]>;
160 def MOVSX64rm32: RI<0x63, MRMSrcMem, (outs GR64:$dst), (ins i32mem:$src),
161 "movs{lq|xd}\t{$src, $dst|$dst, $src}",
162 [(set GR64:$dst, (sextloadi64i32 addr:$src))]>,
163 Sched<[WriteALULd]>, Requires<[In64BitMode]>;
165 // These instructions exist as a consequence of operand size prefix having
166 // control of the destination size, but not the input size. Only support them
167 // for the disassembler.
168 let isCodeGenOnly = 1, ForceDisassemble = 1, hasSideEffects = 0 in {
169 def MOVSX16rr32: I<0x63, MRMSrcReg, (outs GR16:$dst), (ins GR32:$src),
170 "movs{lq|xd}\t{$src, $dst|$dst, $src}", []>,
171 Sched<[WriteALU]>, OpSize16, Requires<[In64BitMode]>;
172 def MOVSX32rr32: I<0x63, MRMSrcReg, (outs GR32:$dst), (ins GR32:$src),
173 "movs{lq|xd}\t{$src, $dst|$dst, $src}", []>,
174 Sched<[WriteALU]>, OpSize32, Requires<[In64BitMode]>;
176 def MOVSX16rm32: I<0x63, MRMSrcMem, (outs GR16:$dst), (ins i32mem:$src),
177 "movs{lq|xd}\t{$src, $dst|$dst, $src}", []>,
178 Sched<[WriteALULd]>, OpSize16, Requires<[In64BitMode]>;
179 def MOVSX32rm32: I<0x63, MRMSrcMem, (outs GR32:$dst), (ins i32mem:$src),
180 "movs{lq|xd}\t{$src, $dst|$dst, $src}", []>,
181 Sched<[WriteALULd]>, OpSize32, Requires<[In64BitMode]>;
183 } // isCodeGenOnly = 1, ForceDisassemble = 1, hasSideEffects = 0
185 // movzbq and movzwq encodings for the disassembler
186 let hasSideEffects = 0 in {
187 def MOVZX64rr8 : RI<0xB6, MRMSrcReg, (outs GR64:$dst), (ins GR8:$src),
188 "movz{bq|x}\t{$src, $dst|$dst, $src}", []>,
189 TB, Sched<[WriteALU]>;
191 def MOVZX64rm8 : RI<0xB6, MRMSrcMem, (outs GR64:$dst), (ins i8mem:$src),
192 "movz{bq|x}\t{$src, $dst|$dst, $src}", []>,
193 TB, Sched<[WriteALULd]>;
194 def MOVZX64rr16 : RI<0xB7, MRMSrcReg, (outs GR64:$dst), (ins GR16:$src),
195 "movz{wq|x}\t{$src, $dst|$dst, $src}", []>,
196 TB, Sched<[WriteALU]>;
198 def MOVZX64rm16 : RI<0xB7, MRMSrcMem, (outs GR64:$dst), (ins i16mem:$src),
199 "movz{wq|x}\t{$src, $dst|$dst, $src}", []>,
200 TB, Sched<[WriteALULd]>;
203 // 64-bit zero-extension patterns use SUBREG_TO_REG and an operation writing a
205 def : Pat<(i64 (zext GR8:$src)),
206 (SUBREG_TO_REG (i64 0), (MOVZX32rr8 GR8:$src), sub_32bit)>;
207 def : Pat<(zextloadi64i8 addr:$src),
208 (SUBREG_TO_REG (i64 0), (MOVZX32rm8 addr:$src), sub_32bit)>;
210 def : Pat<(i64 (zext GR16:$src)),
211 (SUBREG_TO_REG (i64 0), (MOVZX32rr16 GR16:$src), sub_32bit)>;
212 def : Pat<(zextloadi64i16 addr:$src),
213 (SUBREG_TO_REG (i64 0), (MOVZX32rm16 addr:$src), sub_32bit)>;
215 // The preferred way to do 32-bit-to-64-bit zero extension on x86-64 is to use a
216 // SUBREG_TO_REG to utilize implicit zero-extension, however this isn't possible
217 // when the 32-bit value is defined by a truncate or is copied from something
218 // where the high bits aren't necessarily all zero. In such cases, we fall back
219 // to these explicit zext instructions.
220 def : Pat<(i64 (zext GR32:$src)),
221 (SUBREG_TO_REG (i64 0), (MOV32rr GR32:$src), sub_32bit)>;
222 def : Pat<(i64 (zextloadi64i32 addr:$src)),
223 (SUBREG_TO_REG (i64 0), (MOV32rm addr:$src), sub_32bit)>;