Intel 253666-024US Manuel D’Utilisation

Page de 760
Vol. 2A 3-587
INSTRUCTION SET REFERENCE, A-M
MINPS—Return Minimum Packed Single-Precision Floating-Point Values
MINPS—Return Minimum Packed Single-Precision Floating-Point 
Values
Description
Performs a SIMD compare of the packed single-precision floating-point values in the 
destination operand (first operand) and the source operand (second operand), and 
returns the minimum value for each pair of values to the destination operand. The 
source operand can be an XMM register or a 128-bit memory location. The destina-
tion operand is an XMM register.
If the values being compared are both 0.0s (of either sign), the value in the second 
operand (source operand) is returned. If a value in the second operand is an SNaN, 
that SNaN is returned unchanged to the destination (that is, a QNaN version of the 
SNaN is not returned).
If only one value is a NaN (SNaN or QNaN) for this instruction, the second operand 
(source operand), either a NaN or a valid floating-point value, is written to the result. 
If instead of this behavior, it is required that the NaN source operand (from either the 
first or second operand) be returned, the action of MINPS can be emulated using a 
sequence of instructions, such as, a comparison followed by AND, ANDN and OR.
In 64-bit mode, use of the REX.R prefix permits this instruction to access additional 
registers (XMM8-XMM15).
Operation
DEST[63:0] ←
IF ((DEST[31:0] 
0.0) and (SRC[31:0]
 =
 0.0)) 
THEN SRC[31:0];
ELSE IF (DEST[31:0]
 = 
SNaN) THEN SRC[31:0]; FI;
 
ELSE IF (SRC[31:0] 
=
 SNaN) THEN SRC[31:0]; FI;
 
ELSE IF (DEST[31:0] 
>
 SRC[31:0]) 
THEN DEST[31:0] 
ELSE SRC[31:0]; FI; FI;
(* Repeat operation for 2nd and 3rd doublewords *);
DEST[127:64] ← IF 
((DEST127:96] 
0.0) and (SRC[127:96] 
0.0)) 
THEN SRC[127:96];
ELSE IF (DEST[127:96] 
SNaN) THEN SRC[127:96]; FI;
 
ELSE IF (SRC[127:96]
 = 
SNaN) THEN SRC[127:96]; FI;
 
ELSE IF (DEST[127:96] 
<
 SRC[127:96]) 
Opcode
Instruction
64-Bit 
Mode
Compat/
Leg Mode
Description
0F 5D /r
MINPS xmm1
xmm2/m128
Valid
Valid
Return the minimum single-precision 
floating-point values between 
xmm2/m128 and xmm1.