x86 Instruction Set Reference

# CVTTSD2SI

# Convert with Truncation Scalar Double-Precision Floating-Point Value to Signed Doubleword Integer

Opcode Mnemonic Description
F2 0F 2C /r CVTTSD2SI r32, xmm/m64 Convert one double-precision floating-point value from xmm/m64 to one signed doubleword integer in r32 using truncation.

# Description

Converts a double-precision floating-point value in the source operand (second operand) to a signed doubleword integer in the destination operand (first operand). The source operand can be an XMM register or a 64-bit memory location. The destination operand is a general-purpose register. When the source operand is an XMM register, the double-precision floating-point value is contained in the low quadword of the 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.

# Operation

Destination[0..31] = ConvertDoubleToIntegerTruncate(Source[0..63]);
1
2

# SIMD Floating-Point Exceptions

Invalid, Precision.

# Protected Mode Exceptions
#GP(0) For an illegal memory operand effective address in the CS, DS, ES, FS or GS segments.
#GP(0) For an illegal memory operand effective address in the CS, DS, ES, FS or GS segments.
#SS(0) For an illegal address in the SS segment.
#PF(fault-code) For a page fault.
#NM If TS in CR0 is set.
#XM If an unmasked SIMD floating-point exception and OSXMMEXCPT in CR4 is 1.
#UD If an unmasked SIMD floating-point exception and OSXMMEXCPT in CR4 is 0. If EM in CR0 is set. If OSFXSR in CR4 is 0. If CPUID feature flag SSE2 is 0.

# Real-Address Mode Exceptions
#GP(0) If any part of the operand lies outside the effective address space from 0 to FFFFH.
#GP(0) If any part of the operand lies outside the effective address space from 0 to FFFFH.
#NM If TS in CR0 is set.
#XM If an unmasked SIMD floating-point exception and OSXMMEXCPT in CR4 is 1.

# Virtual-8086 Mode Exceptions

Same exceptions as in Real Address Mode
#PF(fault-code) For a page fault.
#PF(fault-code) For a page fault.
Instruction Latency Throughput Execution Unit
CPUID 0F3n/0F2n 0F3n/0F2n 0F2n
CVTTSD2SI r32, xmm 8/8 2/2 FP_ADD FP_MISC

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