SUBPD — Subtract Packed Double Precision Floating-Point Values

Instruction Operand Encoding ¶

Description ¶

Performs a SIMD subtract of the two, four or eight packed double precision floating-point values of the second Source operand from the first Source operand, and stores the packed double precision floating-point results in the destination operand.

VEX.128 and EVEX.128 encoded versions: The second source operand is an XMM register or an 128-bit memory location. The first source operand and destination operands are XMM registers. Bits (MAXVL-1:128) of the corresponding destination register are zeroed.

VEX.256 and EVEX.256 encoded versions: The second source operand is an YMM register or an 256-bit memory location. The first source operand and destination operands are YMM registers. Bits (MAXVL-1:256) of the corresponding destination register are zeroed.

EVEX.512 encoded version: The second source operand is a ZMM register, a 512-bit memory location or a 512-bit vector broadcasted from a 64-bit memory location. The first source operand and destination operands are ZMM registers. The destination operand is conditionally updated according to the writemask.

128-bit Legacy SSE version: The second source can be an XMM register or an 128-bit memory location. The destination is not distinct from the first source XMM register and the upper Bits (MAXVL-1:128) of the corresponding register destination are unmodified.

Operation ¶

VSUBPD (EVEX Encoded Versions When SRC2 Operand is a Vector Register) ¶

(KL, VL) = (2, 128), (4, 256), (8, 512)
IF (VL = 512) AND (EVEX.b = 1)
    THEN
        SET_ROUNDING_MODE_FOR_THIS_INSTRUCTION(EVEX.RC);
    ELSE
        SET_ROUNDING_MODE_FOR_THIS_INSTRUCTION(MXCSR.RC);
FI;
FOR j := 0 TO KL-1
    i := j * 64
    IF k1[j] OR *no writemask*
        THEN DEST[i+63:i] := SRC1[i+63:i] - SRC2[i+63:i]
    ELSE
        IF *merging-masking* ; merging-masking
            THEN *DEST[63:0] remains unchanged*
            ELSE ; zeroing-masking
                DEST[63:0] := 0
        FI;
    FI;
ENDFOR
DEST[MAXVL-1:VL] := 0

VSUBPD (EVEX Encoded Versions When SRC2 Operand is a Memory Source) ¶

(KL, VL) = (2, 128), (4, 256), (8, 512)
FOR j := 0 TO KL-1
    i := j * 64
    IF k1[j] OR *no writemask* THEN
            IF (EVEX.b = 1)
                THEN DEST[i+63:i] := SRC1[i+63:i] - SRC2[63:0];
                ELSE EST[i+63:i] := SRC1[i+63:i] - SRC2[i+63:i];
            FI;
    ELSE
        IF *merging-masking* ; merging-masking
            THEN *DEST[63:0] remains unchanged*
            ELSE ; zeroing-masking
                DEST[63:0] := 0
        FI;
    FI;
ENDFOR
DEST[MAXVL-1:VL] := 0

VSUBPD (VEX.256 Encoded Version) ¶

DEST[63:0] := SRC1[63:0] - SRC2[63:0]
DEST[127:64] := SRC1[127:64] - SRC2[127:64]
DEST[191:128] := SRC1[191:128] - SRC2[191:128]
DEST[255:192] := SRC1[255:192] - SRC2[255:192]
DEST[MAXVL-1:256] := 0

VSUBPD (VEX.128 Encoded Version) ¶

DEST[63:0] := SRC1[63:0] - SRC2[63:0]
DEST[127:64] := SRC1[127:64] - SRC2[127:64]
DEST[MAXVL-1:128] := 0

SUBPD (128-bit Legacy SSE Version) ¶

DEST[63:0] := DEST[63:0] - SRC[63:0]
DEST[127:64] := DEST[127:64] - SRC[127:64]
DEST[MAXVL-1:128] (Unmodified)

Intel C/C++ Compiler Intrinsic Equivalent ¶

VSUBPD __m512d _mm512_sub_pd (__m512d a, __m512d b);

VSUBPD __m512d _mm512_mask_sub_pd (__m512d s, __mmask8 k, __m512d a, __m512d b);

VSUBPD __m512d _mm512_maskz_sub_pd (__mmask8 k, __m512d a, __m512d b);

VSUBPD __m512d _mm512_sub_round_pd (__m512d a, __m512d b, int);

VSUBPD __m512d _mm512_mask_sub_round_pd (__m512d s, __mmask8 k, __m512d a, __m512d b, int);

VSUBPD __m512d _mm512_maskz_sub_round_pd (__mmask8 k, __m512d a, __m512d b, int);

VSUBPD __m256d _mm256_sub_pd (__m256d a, __m256d b);

VSUBPD __m256d _mm256_mask_sub_pd (__m256d s, __mmask8 k, __m256d a, __m256d b);

VSUBPD __m256d _mm256_maskz_sub_pd (__mmask8 k, __m256d a, __m256d b);

SUBPD __m128d _mm_sub_pd (__m128d a, __m128d b);

VSUBPD __m128d _mm_mask_sub_pd (__m128d s, __mmask8 k, __m128d a, __m128d b);

VSUBPD __m128d _mm_maskz_sub_pd (__mmask8 k, __m128d a, __m128d b);

SIMD Floating-Point Exceptions ¶

Overflow, Underflow, Invalid, Precision, Denormal.

Other Exceptions ¶

VEX-encoded instructions, see Table 2-19, “Type 2 Class Exception Conditions.”

EVEX-encoded instructions, see Table 2-46, “Type E2 Class Exception Conditions.”