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Volume 3: Instruction Reference
3:63
fchkf
fchkf — Floating-point Check Flags
Format:
(
qp
) fchkf.
sf target
25
Description:
The flags in FPSR.
sf
.flags are compared with FPSR.s0.flags and FPSR.traps. If any flags
set in FPSR.
sf
.flags correspond to FPSR.traps which are enabled, or if any flags set in
FPSR.
sf
.flags are not set in FPSR.s0.flags, then a branch to
target
25
is taken.
The
target
25
operand, specifies a label to branch to. This is encoded in the instruction
as a signed immediate displacement (
imm
21
) between the target bundle and the bundle
containing this instruction (
imm
21
=
target
25
- IP >> 4).
The branching behavior of this instruction can be optionally unimplemented. If the
instruction would have branched, and the branching behavior is not implemented, then
a Speculative Operation fault is taken and the value specified by
imm
21
is zero-extended
and placed in the Interruption Immediate control register (IIM). The fault handler
emulates the branch by sign-extending the IIM value, adding it to IIP and returning.
The mnemonic values for
sf
are given in
.
Operation:
if (PR[
qp
]) {
switch (sf) {
case ‘s0’:
tmp_flags = AR[FPSR].sf0.flags;
break;
case ‘s1’:
tmp_flags = AR[FPSR].sf1.flags;
break;
case ‘s2’:
tmp_flags = AR[FPSR].sf2.flags;
break;
case ‘s3’:
tmp_flags = AR[FPSR].sf3.flags;
break;
}
if ((tmp_flags & ~AR[FPSR].traps) || (tmp_flags & ~AR[FPSR].sf0.flags)) {
if (check_branch_implemented(FCHKF)) {
taken_branch = 1;
IP = IP + sign_ext((
imm
21
<< 4), 25);
if (!impl_uia_fault_supported() &&
((PSR.it && unimplemented_virtual_address(IP, PSR.vm))
|| (!PSR.it && unimplemented_physical_address(IP)))
unimplemented_instruction_address_trap(0, IP);
if (PSR.tb)
taken_branch_trap();
} else
speculation_fault(FCHKF, zero_ext(
imm
21
, 21));
}
}
FP Exceptions:
None
Interruptions:
Speculative Operation fault
Taken Branch trap
Unimplemented Instruction Address trap
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 ...