The entry code in ArmPlatformStackSet () is a 1:1 transliteration of the
ARM version, which uses the callee preserved registers r3 - r7 (*) to
preserve the function arguments and the link register across a call to
ArmPlatformIsPrimaryCore ().
However, x3 - x7 are not callee preserved on AARCH64, and so we should use
registers >= x19 instead. While we're at it, drop an unnecessary preserve
of the link register, and simplify/deobfuscate the calculation of the
secondary stack position.
(*) Note that r3 is not actually a callee saved register even on ARM.
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Leif Lindholm <leif.lindholm@linaro.org>
Annotate functions with ASM_FUNC() so that they are emitted into
separate sections.
While we're at it, replace some inefficient uses of LoadConstantToReg(),
and remove the workaround that was added to allow conditional branches
to functions with external linkage.
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Leif Lindholm <leif.lindholm@linaro.org>