Differential revision: https://reviews.llvm.org/D72701
The patch adds a new option ABI for Hexagon. It primary deals with
the way variable arguments are passed and is use in the Hexagon Linux Musl
environment.
If a callee function has a variable argument list, it must perform the
following operations to set up its function prologue:
1. Determine the number of registers which could have been used for passing
unnamed arguments. This can be calculated by counting the number of
registers used for passing named arguments. For example, if the callee
function is as follows:
int foo(int a, ...){ ... }
... then register R0 is used to access the argument ' a '. The registers
available for passing unnamed arguments are R1, R2, R3, R4, and R5.
2. Determine the number and size of the named arguments on the stack.
3. If the callee has named arguments on the stack, it should copy all of these
arguments to a location below the current position on the stack, and the
difference should be the size of the register-saved area plus padding
(if any is necessary).
The register-saved area constitutes all the registers that could have
been used to pass unnamed arguments. If the number of registers forming
the register-saved area is odd, it requires 4 bytes of padding; if the
number is even, no padding is required. This is done to ensure an 8-byte
alignment on the stack. For example, if the callee is as follows:
int foo(int a, ...){ ... }
... then the named arguments should be copied to the following location:
current_position - 5 (for R1-R5) * 4 (bytes) - 4 (bytes of padding)
If the callee is as follows:
int foo(int a, int b, ...){ ... }
... then the named arguments should be copied to the following location:
current_position - 4 (for R2-R5) * 4 (bytes) - 0 (bytes of padding)
4. After any named arguments have been copied, copy all the registers that
could have been used to pass unnamed arguments on the stack. If the number
of registers is odd, leave 4 bytes of padding and then start copying them
on the stack; if the number is even, no padding is required. This
constitutes the register-saved area. If padding is required, ensure
that the start location of padding is 8-byte aligned. If no padding is
required, ensure that the start location of the on-stack copy of the
first register which might have a variable argument is 8-byte aligned.
5. Decrement the stack pointer by the size of register saved area plus the
padding. For example, if the callee is as follows:
int foo(int a, ...){ ... } ;
... then the decrement value should be the following:
5 (for R1-R5) * 4 (bytes) + 4 (bytes of padding) = 24 bytes
The decrement should be performed before the allocframe instruction.
Increment the stack-pointer back by the same amount before returning
from the function.
to reflect the new license.
We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.
Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.
llvm-svn: 351636
They can be deleted or replicated, so the cache may become outdated.
They only need to be visited once during frame lowering, so just scan
the function instead.
llvm-svn: 279297
- Do not optimize stack slots in optnone functions.
- Get aligned-base register from HexagonMachineFunctionInfo instead of
looking for ALIGNA instruction in the function's body.
llvm-svn: 264580
The patch is generated using this command:
tools/clang/tools/extra/clang-tidy/tool/run-clang-tidy.py -fix \
-checks=-*,llvm-namespace-comment -header-filter='llvm/.*|clang/.*' \
llvm/lib/
Thanks to Eugene Kosov for the original patch!
llvm-svn: 240137
Add header guards to files that were missing guards. Remove #endif comments
as they don't seem common in LLVM (we can easily add them back if we decide
they're useful)
Changes made by clang-tidy with minor tweaks.
llvm-svn: 215558
subsequent changes are easier to review. About to fix some layering
issues, and wanted to separate out the necessary churn.
Also comment and sink the include of "Windows.h" in three .inc files to
match the usage in Memory.inc.
llvm-svn: 198685
This patch removes most of the trivial cases of weak vtables by pinning them to
a single object file. The memory leaks in this version have been fixed. Thanks
Alexey for pointing them out.
Differential Revision: http://llvm-reviews.chandlerc.com/D2068
Reviewed by Andy
llvm-svn: 195064
This change is incorrect. If you delete virtual destructor of both a base class
and a subclass, then the following code:
Base *foo = new Child();
delete foo;
will not cause the destructor for members of Child class. As a result, I observe
plently of memory leaks. Notable examples I investigated are:
ObjectBuffer and ObjectBufferStream, AttributeImpl and StringSAttributeImpl.
llvm-svn: 194997
This patch removes most of the trivial cases of weak vtables by pinning them to
a single object file.
Differential Revision: http://llvm-reviews.chandlerc.com/D2068
Reviewed by Andy
llvm-svn: 194865
Sid Manning