4:364
Volume 4: Base IA-32 Instruction Reference
SHRD—Double Precision Shift Right
Description
Shifts the first operand (destination operand) to the right the number of bits specified
by the third operand (count operand). The second operand (source operand) provides
bits to shift in from the left (starting with the most significant bit of the destination
operand). The destination operand can be a register or a memory location; the source
operand is a register. The count operand is an unsigned integer that can be an
immediate byte or the contents of the CL register. Only bits 0 through 4 of the count
are used, which masks the count to a value between 0 and 31. If the count is greater
than the operand size, the result in the destination operand is undefined.
If the count is 1 or greater, the CF flag is filled with the last bit shifted out of the
destination operand. For a 1-bit shift, the OF flag is set if a sign change occurred;
otherwise, it is cleared. If the count operand is 0, the flags are not affected.
The SHRD instruction is useful for multiprecision shifts of 64 bits or more.
Operation
COUNT
COUNT MOD 32;
SIZE
OperandSize
IF COUNT = 0
THEN
no operation
ELSE
IF COUNT
SIZE
THEN (* Bad parameters *)
DEST is undefined;
CF, OF, SF, ZF, AF, PF are undefined;
ELSE (* Perform the shift *)
CF
BIT[DEST, COUNT - 1]; (* last bit shifted out on exit *)
FOR i
0 TO SIZE - 1 - COUNT
DO
BIT[DEST, i]
BIT[DEST
,
i - COUNT];
OD;
FOR i
SIZE - COUNT TO SIZE - 1
DO
BIT[DEST
,
i]
BIT[inBits,i+COUNT - SIZE];
OD;
FI;
FI;
Opcode
Instruction
Description
0F AC
SHRD
r/m16,r16,imm8
Shift
r/m16
to right
imm8
places while shifting bits from
r16
in
from the left
0F AD
SHRD
r/m16,r16
,CL
Shift
r/m16
to right CL places while shifting bits from
r16
in from
the left
0F AC
SHRD
r/m32,r32,imm8
Shift
r/m32
to right
imm8
places while shifting bits from
r32
in
from the left
0F AD
SHRD
r/m32,r32
,CL
Shift
r/m32
to right CL places while shifting bits from
r32
in from
the left
Содержание ITANIUM ARCHITECTURE - SOFTWARE DEVELOPERS VOLUME 3 REV 2.3
Страница 1: ......
Страница 11: ...x Intel Itanium Architecture Software Developer s Manual Rev 2 3 ...
Страница 12: ...1 1 Intel Itanium Architecture Software Developer s Manual Rev 2 3 Part I Application Architecture Guide ...
Страница 13: ...1 2 Intel Itanium Architecture Software Developer s Manual Rev 2 3 ...
Страница 33: ...1 22 Volume 1 Part 1 Introduction to the Intel Itanium Architecture ...
Страница 57: ...1 46 Volume 1 Part 1 Execution Environment ...
Страница 147: ...1 136 Intel Itanium Architecture Software Developer s Manual Rev 2 3 ...
Страница 149: ...1 138 Volume 1 Part 2 About the Optimization Guide ...
Страница 191: ...1 180 Volume 1 Part 2 Predication Control Flow and Instruction Stream ...
Страница 230: ......
Страница 248: ...236 Intel Itanium Architecture Software Developer s Manual Rev 2 3 ...
Страница 249: ...2 1 Intel Itanium Architecture Software Developer s Manual Rev 2 3 Part I System Architecture Guide ...
Страница 250: ...2 2 Intel Itanium Architecture Software Developer s Manual Rev 2 3 ...
Страница 264: ...2 16 Volume 2 Part 1 Intel Itanium System Environment ...
Страница 380: ...2 132 Volume 2 Part 1 Interruptions ...
Страница 398: ...2 150 Volume 2 Part 1 Register Stack Engine ...
Страница 486: ...2 238 Volume 2 Part 1 IA 32 Interruption Vector Descriptions ...
Страница 749: ...2 501 Intel Itanium Architecture Software Developer s Manual Rev 2 3 Part II System Programmer s Guide ...
Страница 750: ...2 502 Intel Itanium Architecture Software Developer s Manual Rev 2 3 ...
Страница 754: ...2 506 Volume 2 Part 2 About the System Programmer s Guide ...
Страница 796: ...2 548 Volume 2 Part 2 Interruptions and Serialization ...
Страница 808: ...2 560 Volume 2 Part 2 Context Management ...
Страница 842: ...2 594 Volume 2 Part 2 Floating point System Software ...
Страница 850: ...2 602 Volume 2 Part 2 IA 32 Application Support ...
Страница 862: ...2 614 Volume 2 Part 2 External Interrupt Architecture ...
Страница 870: ...2 622 Volume 2 Part 2 Performance Monitoring Support ...
Страница 891: ......
Страница 941: ...3 42 Volume 3 Instruction Reference cmp illegal_operation_fault PR p1 0 PR p2 0 Interruptions Illegal Operation fault ...
Страница 1099: ...3 200 Volume 3 Instruction Reference padd Interruptions Illegal Operation fault ...
Страница 1191: ...3 292 Volume 3 Pseudo Code Functions Intel Itanium Architecture Software Developer s Manual Rev 2 3 ...
Страница 1295: ...3 396 Volume 3 Resource and Dependency Semantics ...
Страница 1296: ......
Страница 1302: ...402 Intel Itanium Architecture Software Developer s Manual Rev 2 3 ...
Страница 1494: ...4 192 Volume 4 Base IA 32 Instruction Reference FWAIT Wait See entry for WAIT ...
Страница 1564: ...4 262 Volume 4 Base IA 32 Instruction Reference LES Load Full Pointer See entry for LDS LES LFS LGS LSS ...
Страница 1565: ...Volume 4 Base IA 32 Instruction Reference 4 263 LFS Load Full Pointer See entry for LDS LES LFS LGS LSS ...
Страница 1568: ...4 266 Volume 4 Base IA 32 Instruction Reference LGS Load Full Pointer See entry for LDS LES LFS LGS LSS ...
Страница 1583: ...Volume 4 Base IA 32 Instruction Reference 4 281 LSS Load Full Pointer See entry for LDS LES LFS LGS LSS ...
Страница 1647: ...Volume 4 Base IA 32 Instruction Reference 4 345 ROL ROR Rotate See entry for RCL RCR ROL ROR ...
Страница 1663: ...Volume 4 Base IA 32 Instruction Reference 4 361 SHL SHR Shift Instructions See entry for SAL SAR SHL SHR ...
Страница 1668: ...4 366 Volume 4 Base IA 32 Instruction Reference SIDT Store Interrupt Descriptor Table Register See entry for SGDT SIDT ...
Страница 1884: ...4 582 Volume 4 IA 32 SSE Instruction Reference ...
Страница 1885: ...Index Intel Itanium Architecture Software Developer s Manual Rev 2 3 Index ...
Страница 1886: ...Index Intel Itanium Architecture Software Developer s Manual Rev 2 3 ...
Страница 1898: ...INDEX Index 12 Index for Volumes 1 2 3 and 4 ...