1 //===-- X86InstrExtension.td - Sign and Zero Extensions ----*- tablegen -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file describes the sign and zero extension operations.
12 //===----------------------------------------------------------------------===//
14 let hasSideEffects = 0 in {
15 let Defs = [AX], Uses = [AL] in // AX = signext(AL)
16 def CBW : I<0x98, RawFrm, (outs), (ins),
17 "{cbtw|cbw}", []>, OpSize16, Sched<[WriteALU]>;
18 let Defs = [EAX], Uses = [AX] in // EAX = signext(AX)
19 def CWDE : I<0x98, RawFrm, (outs), (ins),
20 "{cwtl|cwde}", []>, OpSize32, Sched<[WriteALU]>;
22 let Defs = [AX,DX], Uses = [AX] in // DX:AX = signext(AX)
23 def CWD : I<0x99, RawFrm, (outs), (ins),
24 "{cwtd|cwd}", []>, OpSize16, Sched<[WriteALU]>;
25 let Defs = [EAX,EDX], Uses = [EAX] in // EDX:EAX = signext(EAX)
26 def CDQ : I<0x99, RawFrm, (outs), (ins),
27 "{cltd|cdq}", []>, OpSize32, Sched<[WriteALU]>;
30 let Defs = [RAX], Uses = [EAX] in // RAX = signext(EAX)
31 def CDQE : RI<0x98, RawFrm, (outs), (ins),
32 "{cltq|cdqe}", []>, Sched<[WriteALU]>;
34 let Defs = [RAX,RDX], Uses = [RAX] in // RDX:RAX = signext(RAX)
35 def CQO : RI<0x99, RawFrm, (outs), (ins),
36 "{cqto|cqo}", []>, Sched<[WriteALU]>;
39 // Sign/Zero extenders
40 let hasSideEffects = 0 in {
41 def MOVSX16rr8 : I<0xBE, MRMSrcReg, (outs GR16:$dst), (ins GR8:$src),
42 "movs{bw|x}\t{$src, $dst|$dst, $src}", []>,
43 TB, OpSize16, Sched<[WriteALU]>;
45 def MOVSX16rm8 : I<0xBE, MRMSrcMem, (outs GR16:$dst), (ins i8mem:$src),
46 "movs{bw|x}\t{$src, $dst|$dst, $src}", []>,
47 TB, OpSize16, Sched<[WriteALULd]>;
48 } // hasSideEffects = 0
49 def MOVSX32rr8 : I<0xBE, MRMSrcReg, (outs GR32:$dst), (ins GR8:$src),
50 "movs{bl|x}\t{$src, $dst|$dst, $src}",
51 [(set GR32:$dst, (sext GR8:$src))]>, TB,
52 OpSize32, Sched<[WriteALU]>;
53 def MOVSX32rm8 : I<0xBE, MRMSrcMem, (outs GR32:$dst), (ins i8mem :$src),
54 "movs{bl|x}\t{$src, $dst|$dst, $src}",
55 [(set GR32:$dst, (sextloadi32i8 addr:$src))]>, TB,
56 OpSize32, Sched<[WriteALULd]>;
57 def MOVSX32rr16: I<0xBF, MRMSrcReg, (outs GR32:$dst), (ins GR16:$src),
58 "movs{wl|x}\t{$src, $dst|$dst, $src}",
59 [(set GR32:$dst, (sext GR16:$src))]>, TB,
60 OpSize32, Sched<[WriteALU]>;
61 def MOVSX32rm16: I<0xBF, MRMSrcMem, (outs GR32:$dst), (ins i16mem:$src),
62 "movs{wl|x}\t{$src, $dst|$dst, $src}",
63 [(set GR32:$dst, (sextloadi32i16 addr:$src))]>,
64 OpSize32, TB, Sched<[WriteALULd]>;
66 let hasSideEffects = 0 in {
67 def MOVZX16rr8 : I<0xB6, MRMSrcReg, (outs GR16:$dst), (ins GR8:$src),
68 "movz{bw|x}\t{$src, $dst|$dst, $src}", []>,
69 TB, OpSize16, Sched<[WriteALU]>;
71 def MOVZX16rm8 : I<0xB6, MRMSrcMem, (outs GR16:$dst), (ins i8mem:$src),
72 "movz{bw|x}\t{$src, $dst|$dst, $src}", []>,
73 TB, OpSize16, Sched<[WriteALULd]>;
74 } // hasSideEffects = 0
75 def MOVZX32rr8 : I<0xB6, MRMSrcReg, (outs GR32:$dst), (ins GR8 :$src),
76 "movz{bl|x}\t{$src, $dst|$dst, $src}",
77 [(set GR32:$dst, (zext GR8:$src))]>, TB,
78 OpSize32, Sched<[WriteALU]>;
79 def MOVZX32rm8 : I<0xB6, MRMSrcMem, (outs GR32:$dst), (ins i8mem :$src),
80 "movz{bl|x}\t{$src, $dst|$dst, $src}",
81 [(set GR32:$dst, (zextloadi32i8 addr:$src))]>, TB,
82 OpSize32, Sched<[WriteALULd]>;
83 def MOVZX32rr16: I<0xB7, MRMSrcReg, (outs GR32:$dst), (ins GR16:$src),
84 "movz{wl|x}\t{$src, $dst|$dst, $src}",
85 [(set GR32:$dst, (zext GR16:$src))]>, TB,
86 OpSize32, Sched<[WriteALU]>;
87 def MOVZX32rm16: I<0xB7, MRMSrcMem, (outs GR32:$dst), (ins i16mem:$src),
88 "movz{wl|x}\t{$src, $dst|$dst, $src}",
89 [(set GR32:$dst, (zextloadi32i16 addr:$src))]>,
90 TB, OpSize32, Sched<[WriteALULd]>;
92 // These instructions exist as a consequence of operand size prefix having
93 // control of the destination size, but not the input size. Only support them
94 // for the disassembler.
95 let isCodeGenOnly = 1, ForceDisassemble = 1, hasSideEffects = 0 in {
96 def MOVSX16rr16: I<0xBF, MRMSrcReg, (outs GR16:$dst), (ins GR16:$src),
97 "movs{ww|x}\t{$src, $dst|$dst, $src}",
98 []>, TB, OpSize16, Sched<[WriteALU]>, NotMemoryFoldable;
99 def MOVZX16rr16: I<0xB7, MRMSrcReg, (outs GR16:$dst), (ins GR16:$src),
100 "movz{ww|x}\t{$src, $dst|$dst, $src}",
101 []>, TB, OpSize16, Sched<[WriteALU]>, NotMemoryFoldable;
103 def MOVSX16rm16: I<0xBF, MRMSrcMem, (outs GR16:$dst), (ins i16mem:$src),
104 "movs{ww|x}\t{$src, $dst|$dst, $src}",
105 []>, OpSize16, TB, Sched<[WriteALULd]>, NotMemoryFoldable;
106 def MOVZX16rm16: I<0xB7, MRMSrcMem, (outs GR16:$dst), (ins i16mem:$src),
107 "movz{ww|x}\t{$src, $dst|$dst, $src}",
108 []>, TB, OpSize16, Sched<[WriteALULd]>, NotMemoryFoldable;
110 } // isCodeGenOnly = 1, ForceDisassemble = 1, hasSideEffects = 0
112 // These are the same as the regular MOVZX32rr8 and MOVZX32rm8
113 // except that they use GR32_NOREX for the output operand register class
114 // instead of GR32. This allows them to operate on h registers on x86-64.
115 let hasSideEffects = 0, isCodeGenOnly = 1 in {
116 def MOVZX32rr8_NOREX : I<0xB6, MRMSrcReg,
117 (outs GR32_NOREX:$dst), (ins GR8_NOREX:$src),
118 "movz{bl|x}\t{$src, $dst|$dst, $src}",
119 []>, TB, OpSize32, Sched<[WriteALU]>;
121 def MOVZX32rm8_NOREX : I<0xB6, MRMSrcMem,
122 (outs GR32_NOREX:$dst), (ins i8mem_NOREX:$src),
123 "movz{bl|x}\t{$src, $dst|$dst, $src}",
124 []>, TB, OpSize32, Sched<[WriteALULd]>;
126 def MOVSX32rr8_NOREX : I<0xBE, MRMSrcReg,
127 (outs GR32_NOREX:$dst), (ins GR8_NOREX:$src),
128 "movs{bl|x}\t{$src, $dst|$dst, $src}",
129 []>, TB, OpSize32, Sched<[WriteALU]>;
131 def MOVSX32rm8_NOREX : I<0xBE, MRMSrcMem,
132 (outs GR32_NOREX:$dst), (ins i8mem_NOREX:$src),
133 "movs{bl|x}\t{$src, $dst|$dst, $src}",
134 []>, TB, OpSize32, Sched<[WriteALULd]>;
137 // MOVSX64rr8 always has a REX prefix and it has an 8-bit register
138 // operand, which makes it a rare instruction with an 8-bit register
139 // operand that can never access an h register. If support for h registers
140 // were generalized, this would require a special register class.
141 def MOVSX64rr8 : RI<0xBE, MRMSrcReg, (outs GR64:$dst), (ins GR8 :$src),
142 "movs{bq|x}\t{$src, $dst|$dst, $src}",
143 [(set GR64:$dst, (sext GR8:$src))]>, TB,
145 def MOVSX64rm8 : RI<0xBE, MRMSrcMem, (outs GR64:$dst), (ins i8mem :$src),
146 "movs{bq|x}\t{$src, $dst|$dst, $src}",
147 [(set GR64:$dst, (sextloadi64i8 addr:$src))]>,
148 TB, Sched<[WriteALULd]>;
149 def MOVSX64rr16: RI<0xBF, MRMSrcReg, (outs GR64:$dst), (ins GR16:$src),
150 "movs{wq|x}\t{$src, $dst|$dst, $src}",
151 [(set GR64:$dst, (sext GR16:$src))]>, TB,
153 def MOVSX64rm16: RI<0xBF, MRMSrcMem, (outs GR64:$dst), (ins i16mem:$src),
154 "movs{wq|x}\t{$src, $dst|$dst, $src}",
155 [(set GR64:$dst, (sextloadi64i16 addr:$src))]>,
156 TB, Sched<[WriteALULd]>;
157 def MOVSX64rr32: RI<0x63, MRMSrcReg, (outs GR64:$dst), (ins GR32:$src),
158 "movs{lq|xd}\t{$src, $dst|$dst, $src}",
159 [(set GR64:$dst, (sext GR32:$src))]>,
160 Sched<[WriteALU]>, Requires<[In64BitMode]>;
161 def MOVSX64rm32: RI<0x63, MRMSrcMem, (outs GR64:$dst), (ins i32mem:$src),
162 "movs{lq|xd}\t{$src, $dst|$dst, $src}",
163 [(set GR64:$dst, (sextloadi64i32 addr:$src))]>,
164 Sched<[WriteALULd]>, Requires<[In64BitMode]>;
166 // movzbq and movzwq encodings for the disassembler
167 let hasSideEffects = 0 in {
168 def MOVZX64rr8 : RI<0xB6, MRMSrcReg, (outs GR64:$dst), (ins GR8:$src),
169 "movz{bq|x}\t{$src, $dst|$dst, $src}", []>,
170 TB, Sched<[WriteALU]>;
172 def MOVZX64rm8 : RI<0xB6, MRMSrcMem, (outs GR64:$dst), (ins i8mem:$src),
173 "movz{bq|x}\t{$src, $dst|$dst, $src}", []>,
174 TB, Sched<[WriteALULd]>;
175 def MOVZX64rr16 : RI<0xB7, MRMSrcReg, (outs GR64:$dst), (ins GR16:$src),
176 "movz{wq|x}\t{$src, $dst|$dst, $src}", []>,
177 TB, Sched<[WriteALU]>;
179 def MOVZX64rm16 : RI<0xB7, MRMSrcMem, (outs GR64:$dst), (ins i16mem:$src),
180 "movz{wq|x}\t{$src, $dst|$dst, $src}", []>,
181 TB, Sched<[WriteALULd]>;
184 // 64-bit zero-extension patterns use SUBREG_TO_REG and an operation writing a
186 def : Pat<(i64 (zext GR8:$src)),
187 (SUBREG_TO_REG (i64 0), (MOVZX32rr8 GR8:$src), sub_32bit)>;
188 def : Pat<(zextloadi64i8 addr:$src),
189 (SUBREG_TO_REG (i64 0), (MOVZX32rm8 addr:$src), sub_32bit)>;
191 def : Pat<(i64 (zext GR16:$src)),
192 (SUBREG_TO_REG (i64 0), (MOVZX32rr16 GR16:$src), sub_32bit)>;
193 def : Pat<(zextloadi64i16 addr:$src),
194 (SUBREG_TO_REG (i64 0), (MOVZX32rm16 addr:$src), sub_32bit)>;
196 // The preferred way to do 32-bit-to-64-bit zero extension on x86-64 is to use a
197 // SUBREG_TO_REG to utilize implicit zero-extension, however this isn't possible
198 // when the 32-bit value is defined by a truncate or is copied from something
199 // where the high bits aren't necessarily all zero. In such cases, we fall back
200 // to these explicit zext instructions.
201 def : Pat<(i64 (zext GR32:$src)),
202 (SUBREG_TO_REG (i64 0), (MOV32rr GR32:$src), sub_32bit)>;
203 def : Pat<(i64 (zextloadi64i32 addr:$src)),
204 (SUBREG_TO_REG (i64 0), (MOV32rm addr:$src), sub_32bit)>;