Efficient parallel floating point exception handling in a processor
    37.
    发明授权
    Efficient parallel floating point exception handling in a processor 有权
    处理器中的高效并行浮点异常处理

    公开(公告)号:US09092226B2

    公开(公告)日:2015-07-28

    申请号:US13325559

    申请日:2011-12-14

    IPC分类号: G06F9/38 G06F9/30

    摘要: Methods and apparatus are provided for handling floating point exceptions in a processor that executes single-instruction multiple-data (SIMD) instructions. In one example a numerical exception is identified for a SIMD floating point operation and SIMD micro-operations are initiated to generate two packed partial results of a packed result for the SIMD floating point operation. A SIMD denormalization micro-operation is initiated to combine the two packed partial results and to denormalize one or more elements of the combined packed partial results to generate a packed result for the SIMD floating point operation having one or more denormal elements. Flags are set and stored with packed partial results to identify denormal elements. In one example a SIMD normalization micro-operation is initiated to generate a normalized pseudo internal floating point representation prior to the SIMD floating point operation when it uses multiplication.

    摘要翻译: 提供了用于处理执行单指令多数据(SIMD)指令的处理器中的浮点异常的方法和装置。 在一个示例中,识别用于SIMD浮点运算的数字异常,并且启动SIMD微操作以生成用于SIMD浮点运算的打包结果的两个打包部分结果。 启动SIMD非规范化微操作以组合两个打包的部分结果并且对组合的打包部分结果的一个或多个元素进行非规范化,以生成具有一个或多个异常元素的SIMD浮点运算的打包结果。 标志被设置和存储与打包部分结果以识别异常元素。 在一个示例中,当SIMD归一化微操作在使用乘法时在SIMD浮点运算之前产生归一化的伪内部浮点表示。

    Leading Change Anticipator Logic
    38.
    发明申请
    Leading Change Anticipator Logic 有权
    领先的变革预期逻辑

    公开(公告)号:US20140188967A1

    公开(公告)日:2014-07-03

    申请号:US13729421

    申请日:2012-12-28

    IPC分类号: G06F17/10

    CPC分类号: G06F7/74 G06F5/012 G06F7/485

    摘要: In one embodiment, a processor includes at least one floating point unit. The at least one floating point unit may include an adder, leading change anticipator (LCA) logic, and a shifter. The adder may be to add a first operand X and a second operand Y to obtain an output operand having a bit length n. The LCA logic may be to: for each bit position i from n−1 to 1, obtain a set of propagation values and a set of bit values based on the first operand X and the second operand Y; and generate a LCA mask based on the set of propagation values and the set of bit values. The shifter may be to normalize the output operand based on the LCA mask. Other embodiments are described and claimed.

    摘要翻译: 在一个实施例中,处理器包括至少一个浮点单元。 所述至少一个浮点单元可以包括加法器,引导改变预测器(LCA)逻辑和移位器。 加法器可以添加第一操作数X和第二操作数Y以获得具有位长度n的输出操作数。 LCA逻辑可以是:对于从n-1到1的每个比特位置i,基于第一操作数X和第二操作数Y获得一组传播值和一组比特值; 并且基于传播值集合和位值集合来生成LCA掩码。 移位器可以是基于LCA掩码来规范化输出操作数。 描述和要求保护其他实施例。

    Performing Reciprocal Instructions With High Accuracy
    39.
    发明申请
    Performing Reciprocal Instructions With High Accuracy 有权
    以高精度执行互惠指令

    公开(公告)号:US20120166509A1

    公开(公告)日:2012-06-28

    申请号:US12976359

    申请日:2010-12-22

    IPC分类号: G06F7/38

    摘要: In one embodiment, the present invention includes a method for receiving a reciprocal instruction and an operand in a processor, accessing an entry of a lookup table based on a portion of the operand and the instruction, generating an encoder output based on a type of the reciprocal instruction and whether the reciprocal instruction is a legacy instruction, and selecting portions of the lookup table entry and input operand to be provided to a reciprocal logic unit based on the encoder output. Other embodiments are described and claimed.

    摘要翻译: 在一个实施例中,本发明包括一种用于在处理器中接收互逆指令和操作数的方法,其基于所述操作数和所述指令的一部分访问查找表的条目,基于所述操作数的类型生成编码器输出 互逆指令以及互易指令是否是遗留指令,以及基于编码器输出来选择要提供给倒数逻辑单元的查找表项和输入操作数的部分。 描述和要求保护其他实施例。

    FUSED MULTIPLY ADD OPERATIONS USING BIT MASKS
    40.
    发明申请
    FUSED MULTIPLY ADD OPERATIONS USING BIT MASKS 有权
    使用位掩码的多功能加密操作

    公开(公告)号:US20140379773A1

    公开(公告)日:2014-12-25

    申请号:US13926175

    申请日:2013-06-25

    IPC分类号: G06F7/483 G06F7/485 G06F7/487

    摘要: Systems and methods of performing a fused multiply add (FMA) operations are provided. In one embodiment, the length of the adder used by the FMA operation is less than 3*N, where N is the number of bits in the mantissa term of a floating point number. A mask may be used to perform the addition portion of the FMA operation using the adder. A second mask may be used to denormalize the result of the addition portion of the FMA operation if an underflow occurs.

    摘要翻译: 提供了执行融合乘法(FMA)操作的系统和方法。 在一个实施例中,由FMA操作使用的加法器的长度小于3 * N,其中N是浮点数的尾数项中的位数。 可以使用掩码来使用加法器来执行FMA操作的相加部分。 如果发生下溢,则可以使用第二掩模来对FMA操作的添加部分的结果进行非规范化。