This patch partially implements the parameter passing rules outlined in the
ELFv2 ABI within TableGen. Specifically, it implements the parameter assignment
of integers, floats, and vectors within registers - where the GPR numbering will
be "skipped" depending on the ordering of floats and vectors that appear within
a parameter list.
As we begin to adopt GlobalISel to the PowerPC backend, there is a need for a
TableGen definition that encapsulates the ELFv2 parameter passing rules. Thus,
this patch also changes the default calling convention that is returned within
the ccAssignFnForCall() function used in our GlobalISel implementation, and also
adds some additional testing of the calling convention that is implemented.
Future patches that build on top of this initial TableGen definition will aim to
add more of the ABI complexities, including support for additional types and
also in-memory arguments.
Differential Revision: https://reviews.llvm.org/D137504
LLVM contains a helpful function for getting the size of a C-style
array: `llvm::array_lengthof`. This is useful prior to C++17, but not as
helpful for C++17 or later: `std::size` already has support for C-style
arrays.
Change call sites to use `std::size` instead.
Differential Revision: https://reviews.llvm.org/D133429
This reverts commit ef8206320769ad31422a803a0d6de6077fd231d2.
- It conflicts with the existing llvm::size in STLExtras, which will now
never be called.
- Calling it without llvm:: breaks C++17 compat
Summary:
SPE passes doubles the same as soft-float, in register pairs as i32
types. This is all handled by the target-independent layer. However,
this is not optimal when splitting or reforming the doubles, as it
pushes to the stack and loads from, on either side.
For instance, to pass a double argument to a function, assuming the
double value is in r5, the sequence currently looks like this:
evstdd 5, X(1)
lwz 3, X(1)
lwz 4, X+4(1)
Likewise, to form a double into r5 from args in r3 and r4:
stw 3, X(1)
stw 4, X+4(1)
evldd 5, X(1)
This optimizes the fence to use SPE instructions. Now, to pass a double
to a function:
mr 4, 5
evmergehi 3, 5, 5
And to form a double into r5 from args in r3 and r4:
evmergelo 5, 3, 4
This is comparable to the way that gcc generates the double splits.
This also fixes a bug with expanding builtins to libcalls, where the
LowerCallTo() code path was generating intermediate illegal type nodes.
Reviewers: nemanjai, hfinkel, joerg
Subscribers: kbarton, jfb, jsji, llvm-commits
Differential Revision: https://reviews.llvm.org/D54583
llvm-svn: 363526
Move the CC analysis implementation to its own .cpp file instead of
duplicating it and artificually using functions in PPCISelLowering.cpp
and PPCFastISel.cpp. Follow-up to the same change done for X86, ARM, and
AArch64.
llvm-svn: 352444