How to store Go pointers from assembly

10 months ago

The Go toolchain includes an assembler with Plan 9 syntax and custom names for platform-specific instructions.
Go's garbage collector is concurrent, minimizing pauses by running alongside application code.
Pointer stores are instrumented with write barriers to inform the GC of new references.
Go avoids instrumenting stack pointer stores for performance, previously requiring a final stack rescan.
Go 1.8 introduced a broader write barrier, reducing stop-the-world pauses significantly.
Handling pointer stores in assembly requires manual write barrier implementation.
Linking to runtime symbols for write barriers is restricted but possible with specific build tags.
Allocating 128-bit aligned slots for concurrent hash tables is tricky in Go, requiring creative solutions.
A workaround for alignment involves manipulating slice types and unsafe pointers.

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