CVSROOT: /cvs
Module name: src
Changes by: kette...@cvs.openbsd.org 2016/12/19 13:03:15
Modified files:
sys/arch/amd64/amd64: acpi_wakecode.S mptramp.S
Log message:
Generating mixed 16-bit/32-bit/64-bit code with clang's integrated
assembler is a bit tricky. It supports the .code16, .code32 and
.code64 directives. But it doesn't know about the data16/data32 and
addr16/addr32 instruction prefixes. Instead it tries to determine
those from the instruction opcode. It mostly succeeds, but there are
a couple of corner cases where clang will generate the "addr32" form
where gas generates the "addr16" form in .code16 segments. That
should be no problem (and just waste a couple of bytes), but it makes
comparing the generated code a bit difficult.
Allow the trampoline code to be compiled with both. For clang #define
away the addr32 prefix and avoid using the data32 prefix by using a
mnemonic that explicitly encodes the size of the operand. Add a few
addr32 prefixes in .code16 blocks to reduce the differences between
code generated by clang and gas.
ok patrick@, deraadt@, mlarkin@
