# CVTTPD2PI
# Convert with Truncation Packed Double-Precision Floating-Point Values to Packed Doubleword Integers
Opcode | Mnemonic | Description |
---|---|---|
66 0F 2C /r | CVTTPD2PI mm, xmm/m128 | Convert two packer double-precision floating-point values from xmm/m128 to two packed signed doubleword integers in mm using truncation. |
# Description
Converts two packed double-precision floating-point values in the source operand (second operand) to two packed signed doubleword integers in the destination operand (first operand).
The source operand can be an XMM register or a 128-bit memory location. The destination operand is an MMX technology register.
When a conversion is inexact, a truncated (round toward zero) result is returned. If a converted result is larger than the maximum signed doubleword integer, the floating-point invalid exception is raised, and if this exception is masked, the indefinite integer value (80000000H) is returned.
This instruction causes a transition from x87 FPU to MMX technology operation (that is, the x87 FPU top-of-stack pointer is set to 0 and the x87 FPU tag word is set to all 0s [valid]). If this instruction is executed while an x87 FPU floating-point exception is pending, the exception is handled before the CVTTPD2PI instruction is executed.
# Operation
Destination[0..31] = ConvertDoubleToIntegerTruncate(Source[0..63]);
Destination[32..63] = ConvertDoubleToIntegerTruncate(Source[64..127]);
2
3
# SIMD Floating-Point Exceptions
Invalid, Precision.
# Protected Mode Exceptions
# Real-Address Mode Exceptions
# Virtual-8086 Mode Exceptions
Same exceptions as in Real Address Mode
#PF(fault-code) | For a page fault. |
Instruction | Latency | Throughput | Execution Unit |
---|---|---|---|
CPUID | 0F3n/0F2n/069n | 0F3n/0F2n/069n | 0F2n |
CVTTPD2PI mm, xmm | 12/11/5 | 3/3/3 | FP_ADD MMX_SHFT MMX_ALU |