image/svg+xml FLD—Load Floating Point Value Description Pushes the source operand onto the FPU register stack. The source operand can be in single-precision, double- precision, or double extended-precision floating-point format. If the source operand is in single-precision or double-precision floating-point format, it is automatically converted to the double extended-precision floating- point format before being pushed on the stack. The FLD instruction can also push the value in a selected FPU register [ST(i)] onto the stack. Here, pushing register ST(0) duplicates the stack top. NOTE When the FLD instruction loads a denormal value and the DM bit in the CW is not masked, an exception is flagged but the value is still pushed onto the x87 stack. This instruction’s operation is the same in non-64-bit modes and 64-bit mode. Operation IF SRC is ST(i) THEN temp := ST(i); FI; TOP := TOP − 1; IF SRC is memory-operand THEN ST(0) := ConvertToDoubleExtendedPrecisionFP(SRC); ELSE (* SRC is ST(i) *) ST(0) := temp; FI; FPU Flags Affected C1Set to 1 if stack overflow occurred; otherwise, set to 0. C0, C2, C3 Undefined. Floating-Point Exceptions #ISStack underflow or overflow occurred. #IASource operand is an SNaN. Does not occur if the source operand is in double extended-preci- sion floating-point format (FLD m80fp or FLD ST(i)). #DSource operand is a denormal value. Does not occur if the source operand is in double extended-precision floating-point format. OpcodeInstruction64-Bit Mode Compat/ Leg Mode Description D9 /0FLD m32fp ValidValidPush m32fp onto the FPU register stack. DD /0FLD m64fp ValidValidPush m64fp onto the FPU register stack. DB /5FLD m80fp ValidValidPush m80fp onto the FPU register stack. D9 C0+iFLD ST(i)ValidValidPush ST(i) onto the FPU register stack. image/svg+xml Protected Mode Exceptions #GP(0)If destination is located in a non-writable segment. If a memory operand effective address is outside the CS, DS, ES, FS, or GS segment limit. If the DS, ES, FS, or GS register is used to access memory and it contains a NULL segment selector. #SS(0)If a memory operand effective address is outside the SS segment limit. #NMCR0.EM[bit 2] or CR0.TS[bit 3] = 1. #PF(fault-code)If a page fault occurs. #AC(0)If alignment checking is enabled and an unaligned memory reference is made while the current privilege level is 3. #UD If the LOCK prefix is used. Real-Address Mode Exceptions #GPIf a memory operand effective address is outside the CS, DS, ES, FS, or GS segment limit. #SSIf a memory operand effective address is outside the SS segment limit. #NMCR0.EM[bit 2] or CR0.TS[bit 3] = 1. #UD If the LOCK prefix is used. Virtual-8086 Mode Exceptions #GP(0)If a memory operand effective address is outside the CS, DS, ES, FS, or GS segment limit. #SS(0)If a memory operand effective address is outside the SS segment limit. #NMCR0.EM[bit 2] or CR0.TS[bit 3] = 1. #PF(fault-code)If a page fault occurs. #AC(0)If alignment checking is enabled and an unaligned memory reference is made. #UD If the LOCK prefix is used. Compatibility Mode Exceptions Same exceptions as in protected mode. 64-Bit Mode Exceptions #SS(0)If a memory address referencing the SS segment is in a non-canonical form. #GP(0)If the memory address is in a non-canonical form. #NMCR0.EM[bit 2] or CR0.TS[bit 3] = 1. #MF If there is a pending x87 FPU exception. #PF(fault-code)If a page fault occurs. #AC(0)If alignment checking is enabled and an unaligned memory reference is made while the current privilege level is 3. #UD If the LOCK prefix is used. This UNOFFICIAL reference was generated from the official Intel® 64 and IA-32 Architectures Software Developer’s Manual by a dumb script. There is no guarantee that some parts aren't mangled or broken and is distributed WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE .