Extend the preserve_most/all calling convention description in LangRef about the

fact that the argument registers will be preserved too.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200441 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Juergen Ributzka 2014-01-30 02:39:00 +00:00
parent ab42578bdd
commit 6bf3966f7f

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@ -366,7 +366,9 @@ added in the future:
calling convention on how arguments and return values are passed, but it
uses a different set of caller/callee-saved registers. This alleviates the
burden of saving and recovering a large register set before and after the
call in the caller.
call in the caller. If the arguments are passed in callee-saved registers,
then they will be preserved by the callee across the call. This doesn't
apply for values returned in callee-saved registers.
- On X86-64 the callee preserves all general purpose registers, except for
R11. R11 can be used as a scratch register. Floating-point registers
@ -397,7 +399,10 @@ added in the future:
convention also behaves identical to the `C` calling convention on how
arguments and return values are passed, but it uses a different set of
caller/callee-saved registers. This removes the burden of saving and
recovering a large register set before and after the call in the caller.
recovering a large register set before and after the call in the caller. If
the arguments are passed in callee-saved registers, then they will be
preserved by the callee across the call. This doesn't apply for values
returned in callee-saved registers.
- On X86-64 the callee preserves all general purpose registers, except for
R11. R11 can be used as a scratch register. Furthermore it also preserves