10 Commits

Author SHA1 Message Date
Dylan McKay
28355efdad [AVR] Save/restore the frame pointer for all functions
A recent commit I made made it so that we only did this for signal or
interrupt handlers. This broke normal functions.

llvm-svn: 301893
2017-05-02 01:57:48 +00:00
Dylan McKay
634339ab40 [AVR] Fix a bug where the frame pointer is clobbered
Because it was a callee-saved register, we automatically generated code
to spill and unspill its original value so that it is restored after the
function returns.

The problem is that this code was being generated before the epilogue.
The epilogue itself uses the Y register, which could be prematurely
restored by the CSR restoration process.

This removes R29R28 from the CSR list and changes the prologue/epilogue
code to handle it explicitly.

llvm-svn: 301887
2017-05-02 00:11:34 +00:00
Dylan McKay
3bb6eb238e [AVR] Enable the frame pointer for all functions
This is a temporary measure while we figure out a way to get the frame
pointer working correctly.

llvm-svn: 301881
2017-05-01 23:16:59 +00:00
Krzysztof Parzyszek
44e25f37ae Move size and alignment information of regclass to TargetRegisterInfo
1. RegisterClass::getSize() is split into two functions:
   - TargetRegisterInfo::getRegSizeInBits(const TargetRegisterClass &RC) const;
   - TargetRegisterInfo::getSpillSize(const TargetRegisterClass &RC) const;
2. RegisterClass::getAlignment() is replaced by:
   - TargetRegisterInfo::getSpillAlignment(const TargetRegisterClass &RC) const;

This will allow making those values depend on subtarget features in the
future.

Differential Revision: https://reviews.llvm.org/D31783

llvm-svn: 301221
2017-04-24 18:55:33 +00:00
Dylan McKay
1e57fa487b [AVR] Add an 'relax memory operation' pass
Summary:
This pass will be used to relax instructions which use out of bounds
memory accesses to equivalent operations that can work with the
addresses.

The pass currently implements relaxation for the STDWPtrQRr instruction.

Without this pass, an assertion error would be hit in the pseudo expansion pass.

In the future, we will need to add more instructions to this pass. We can do
that on a case-by-case basic.

Reviewers: arsenm, kparzysz

Subscribers: wdng, llvm-commits, mgorny

Differential Revision: https://reviews.llvm.org/D27650

llvm-svn: 289517
2016-12-13 05:53:14 +00:00
Dylan McKay
552b7856d3 Fix incorrect assertion in AVRFrameLowering.cpp
This wasn't looking at the right instruction, and would always fail.

llvm-svn: 283640
2016-10-08 01:10:36 +00:00
Dylan McKay
b16b6d5739 [AVR] Don't worry about call frame size when initializing frame pointer
We previously only used the frame pointer if the frame pointer was too
big. This was to work around a bug (described in this old commit)

https://sourceforge.net/p/avr-llvm/code/204/tree//llvm/trunk/AVR/AVRFrameLowering.cpp?diff=50d64d912718465cb887d17a:203

I mistakenly invered the condition assuming it was a typo. I am now
removing it because it doesn't seem to be a problem anymore (plus it's a
dirty hack).

llvm-svn: 283639
2016-10-08 01:10:31 +00:00
Dylan McKay
7c2d41aa9f [AVR] Don't shadow container while iterating in range-based loop
This works on clang, but fails on GCC 4.6

llvm-svn: 283638
2016-10-08 01:09:06 +00:00
Dylan McKay
ea55554803 [AVR] Update return type of dynamic alloca pass
It was recently changed from 'const char*' to StringRef

llvm-svn: 283312
2016-10-05 12:32:24 +00:00
Dylan McKay
192405a31a [AVR] Add the AVR frame lowering code
Summary: This allows AVR to lower frames into assembly code.

Reviewers: arsenm, kparzysz

Subscribers: japaric, wdng, beanz, mgorny

Differential Revision: https://reviews.llvm.org/D25032

llvm-svn: 283311
2016-10-05 11:48:56 +00:00