As reported in <https://github.com/llvm/llvm-project/issues/58929>,
Clang's handling of empty structs in the case of small structs that may
be eligible to be passed using the hard FP calling convention doesn't
match g++. In general, C++ record fields are never empty unless
[[no_unique_address]] is used, but the RISC-V FP ABI overrides this.
After this patch, fields of structs that contain empty records will be
ignored, even in C++, when considering eligibility for the FP calling
convention ('flattening'). It isn't explicitly noted in the RISC-V
psABI, but arrays of empty records will disqualify a struct for
consideration of using the FP calling convention in g++. This patch
matches that behaviour. The psABI issue
<https://github.com/riscv-non-isa/riscv-elf-psabi-doc/issues/358> seeks
to clarify this.
This patch was previously committed but reverted after a bug was found.
This recommit adds additional logic to prevent that bug (adding an extra
check for when a candidate from detectFPCCEligibleStructHelper may not
be valid).
Differential Revision: https://reviews.llvm.org/D142327
This reverts commit 17a58b3ca7ec18585e9ea8ed8b39d72fe36fb6cb and the
minor documentation fix 569e99a471f618b7fdf045d5e96f21d3e3a7f898.
An issue was reported in https://reviews.llvm.org/D142327#inline-1510301
so reverting until it can be investigated and fixed.
Partial progress towards replacing uses of CreateElementBitCast, as it
no longer does what its name suggests.
Reviewed By: barannikov88
Differential Revision: https://reviews.llvm.org/D154229
This commit breaks up CodeGen/TargetInfo.cpp into a set of *.cpp files,
one file per target. There are no functional changes, mostly just code moving.
Non-code-moving changes are:
* A virtual destructor has been added to DefaultABIInfo to pin the vtable to a cpp file.
* A few methods of ABIInfo and DefaultABIInfo were split into declaration + definition
in order to reduce the number of transitive includes.
* Several functions that used to be static have been placed in clang::CodeGen
namespace so that they can be accessed from other cpp files.
RFC: https://discourse.llvm.org/t/rfc-splitting-clangs-targetinfo-cpp/69883
Reviewed By: efriedma
Differential Revision: https://reviews.llvm.org/D148094
