4:186
Volume 4: Base IA-32 Instruction Reference
FSUBR/FSUBRP/FISUBR—Reverse Subtract
(Continued)
When the difference between two operands of like sign is 0, the result is +0, except for
the round toward
mode, in which case the result is
0. This instruction also
guarantees that +0
(
0) = +0, and that
0
(+0) =
0. When the source operand is
an integer 0, it is treated as a +0.
When one operand is
, the result is
of the expected sign. If both operands are
of
the same sign, an invalid-operation exception is generated.
Notes:
Fmeans finite-real number.
Imeans integer.
*indicates floating-point invalid-arithmetic-operand (#IA) exception.
Operation
IF instruction is FISUBR
THEN
DEST
ConvertExtendedReal(SRC)
DEST;
ELSE (* source operand is real number *)
DEST
SRC
DEST;
FI;
IF instruction = FSUBRP
THEN
PopRegisterStack
FI;
FPU Flags Affected
C1
Set to 0 if stack underflow occurred.
Indicates rounding direction if the inexact-result exception (#P) fault
is generated: 0 = not roundup; 1 = roundup.
C0, C2, C3
Undefined.
Table 2-10.
FSUBR Zeros and NaNs
SRC
F
0
+
0
+
F
+
NaN
*
+
+
+
+
+
NaN
DEST
F or
I
F or
0
DEST
DEST
+
F
+
NaN
0
SRC
0
+0
SRC
+
NaN
+
0
SRC
0
0
SRC
+
NaN
+
F or +I
F
DEST
DEST
F or
0
+
NaN
+
*
NaN
NaN
NaN
NaN
NaN
NaN
NaN
NaN
NaN
Summary of Contents for ITANIUM ARCHITECTURE
Page 1: ......
Page 7: ...402 Intel Itanium Architecture Software Developer s Manual Rev 2 3 ...
Page 199: ...4 192 Volume 4 Base IA 32 Instruction Reference FWAIT Wait See entry for WAIT ...
Page 352: ...Volume 4 Base IA 32 Instruction Reference 4 345 ROL ROR Rotate See entry for RCL RCR ROL ROR ...
Page 589: ...4 582 Volume 4 IA 32 SSE Instruction Reference ...
Page 590: ...Index Intel Itanium Architecture Software Developer s Manual Rev 2 3 Index ...
Page 591: ...Index Intel Itanium Architecture Software Developer s Manual Rev 2 3 ...
Page 603: ...INDEX Index 12 Index for Volumes 1 2 3 and 4 ...
Page 604: ......