When dumping shader's assembly with
sha1 of the resulting assembly is also printed, having environment
INTEL_SHADER_ASM_READ_PATH present driver will try to
"%sha1%.bin" file from the path and substitute current
assembly with the one from the file.
The file with the assembly could be generated e.g. with:
./i965_asm --gen=kbl --type=bin test.txt -o 8a6b2ec7dbcf81f962a190408cb47931d20cc148.bin
The main current limitation is that one should be careful with jip offsets when changing the assembly especially with the instruction compaction (better use 'nocompact' debug option).