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Floating & SIMD
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x86-64 Assembly / Floating & SIMD

PXOR

Learn PXOR in x86-64 Assembly through a focused explanation, a dedicated construct-specific example, an engineering boundary, and a mastery check.

10 min read • Advanced

PXOR is an atomic x86-64 Assembly topic inside Floating & SIMD. This lesson focuses on how the PXOR construct is written, what it changes, and when it is the right tool.

Trace the example line by line. Identify the exact syntax for PXOR, the input state before it runs, and the resulting value, control flow, database state, hardware behavior, or runtime effect afterward. Neighboring lessons use different constructs rather than renamed copies of this one.

Topic-specific example

assembly-08-08-pxor.asm
assembly Try It Live 
pxor xmm0,xmm0
Edge case / engineering note

For PXOR, test the boundary that belongs to this exact feature rather than a generic failure case. Check invalid or empty input, NULL/unknown state, numeric limits, transaction or exception behavior, synthesis/runtime constraints, ownership/permission rules, or backtracking/control-flow effects where they apply.

Content source & attribution
Original Syntaxis Content · Original Syntaxis Content

Lesson quizzes

PXOR Mastery Check →
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Packed ADDPS
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Unaligned MOVDQU