Instead of pessimistically copying at least 64 bytes from the VM stack
to the native stack, and popping off the register arguments again
before doing the native call, try to avoid touching the stack completely
if the VM stack frame is <= 64 bytes. Also, if the stack frame does exceed
64 bytes, there is no need to copy the first 64 bytes, since we are passing
those in registers anyway.
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Leif Lindholm <leif.lindholm@linaro.org>
Reviewed-by: Feng Tian <feng.tian@intel.com>
The thunk generation is needlessly complex, given that it attempts to
deal with variable length instructions, which don't exist on AArch64.
So replace it with a simple template coded in assembler, with a matching
struct definition in C. That way, we can create and manipulate the thunks
easily without looping over the instructions looking for 'magic' numbers.
Also, use x16 rather than x9, since it is the architectural register to
use for thunks/veneers.
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Leif Lindholm <leif.lindholm@linaro.org>
Reviewed-by: Feng Tian <feng.tian@intel.com>
Change to consistent // style comments. Also, remove bogus global
definitions for external functions, and move the real exports to
the top of the file.
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Leif Lindholm <leif.lindholm@linaro.org>
Reviewed-by: Feng Tian <feng.tian@intel.com>
Ard Biesheuvel
Jeff Brasen