this completes the basic port of ARM constant islands to Mips16.
More testing, code review, cleanup is in order but basically everything
seems to be working. A bug in gas is preventing some of the runtime
testing but I hope to resolve this soon.
llvm-svn: 196331
in constant islands for Mips16. We introdcuce JalB16 as a synomnym
for Jal16. It makes it easier to read and is also necessary because
Jal16 is a call instruction but JalB16 is being used as a branch.
Various parts of LLVM will not work properly even in this late stage of
the backend if we use what was declared as a call instruction to function
as a branch. For one, basic block labels may not get emitted in some
situations.
llvm-svn: 195968
conditional branches for very large targets. That will be the next small
patch. Everything now should in principle work as good (functionality
wise) as without constant islands so we decided at Mips/Imagination to
make constant islands the default for Mips16 now so that it will get
excercised a lot and this port is still experimentatl though hopefully soon
we will change the status. Some more cleanup and code review is in order
but things are converging fast.
llvm-svn: 195902
to what is needed for constant islands. The prescan method for Mips16 constant
islands will eventually go away. It is only temporary and should be done
earlier when the instructions are first created or from the DAG. If we keep
it here we need to handle better the situation where constant islands
is called multiple times since don't want to prescan more than once.
llvm-svn: 195569
I had to move some code and I moved a declaration forward past it's first use
in the function but by nutty coincidence there was another variable of the same
name and type and with completely unrelated function that was declared globally
in the class so no compilation error ensued.
It required some unusual conditions for it to even matter. Caused test
case casts.c in test-suite to fail during compilation with a duplicate
symbol error. I would have noticed it during final code review for this port.
llvm-svn: 195565
specifically about the .space directive. This allows us to force large
blocks of code to appear in test cases for things like constant islands
without having to make giant test cases to force things like long
branches to take effect.
llvm-svn: 194555
This has no material effect at this time since we don't have a direct
object emitter for mips16 and the assembler can't tell them apart. I
place a comment "16 bit inst" for those so that I can tell them apart in the
output. The constant island pass has only been minimally changed to allow
this. More complete branch work is forthcoming but this is the first
step.
llvm-svn: 194442
of being converted and this path is not relevant to anything at this time
so I have just disabled it for a few days while I'm at the LLVM conference
and don't have time to complete it or properly fix it.
llvm-svn: 194201
we don't have such an operand.
Suprisingly enough, this is never actually accounted for in the
ARM version when determining offset ranges. In both places there is the
comment:
- // FIXME: Make use full range of soimm values.
(soimm = shift operand immediate).
llvm-svn: 194101
Submit the basic port of the rest of ARM constant islands code to Mips.
Two test cases are added which reflect the next level of functionality:
constants getting moved to water areas that are out of range from the
initial placement at the end of the function and basic blocks being split to
create water when none exists that can be used. There is a bunch of this
code that is not complete and has been marked with IN_PROGRESS. I will
finish cleaning this all up during the next week or two and submit the
rest of the test cases. I have elminated some code for dealing with
inline assembly because to me it unecessarily complicates things and
some of the newer features of llvm like function attributies and builtin
assembler give me better tools to solve the alignment issues created
there. Also, for Mips16 I even have the option of not doing constant
islands in the present of inline assembler if I chose. When everything
has been completed I will summarize the port and notify people that
are knowledgable regarding the ARM Constant Islands code so they can
review it in it's entirety if they wish.
llvm-svn: 194053
Two test cases are added which reflect the next level of functionality:
constants getting moved to water areas that are out of range from the
initial placement at the end of the function and basic blocks being split to
create water when none exists that can be used. There is a bunch of this
code that is not complete and has been marked with IN_PROGRESS. I will
finish cleaning this all up during the next week or two and submit the
rest of the test cases. I have elminated some code for dealing with
inline assembly because to me it unecessarily complicates things and
some of the newer features of llvm like function attributies and builtin
assembler give me better tools to solve the alignment issues created
there. Also, for Mips16 I even have the option of not doing constant
islands in the present of inline assembler if I chose.
llvm-svn: 194019
Before I just ported the shell of the pass. I've tried to keep everything
nearly identical to the ARM version. I think it will be very easy to eventually
merge these two and create a new more general pass that other targets can
use. I have some improvements I would like to make to allow pools to
be shared across functions and some other things. When I'm all done we
can think about making a more general pass. More to be ported but the
basic mechanism works now almost as good as gcc mips16.
llvm-svn: 193509
and mips16 on a per function basis.
Because this patch is somewhat involved I have provide an overview of the
key pieces of it.
The patch is written so as to not change the behavior of the non mixed
mode. We have tested this a lot but it is something new to switch subtargets
so we don't want any chance of regression in the mainline compiler until
we have more confidence in this.
Mips32/64 are very different from Mip16 as is the case of ARM vs Thumb1.
For that reason there are derived versions of the register info, frame info,
instruction info and instruction selection classes.
Now we register three separate passes for instruction selection.
One which is used to switch subtargets (MipsModuleISelDAGToDAG.cpp) and then
one for each of the current subtargets (Mips16ISelDAGToDAG.cpp and
MipsSEISelDAGToDAG.cpp).
When the ModuleISel pass runs, it determines if there is a need to switch
subtargets and if so, the owning pointers in MipsTargetMachine are
appropriately changed.
When 16Isel or SEIsel is run, they will return immediately without doing
any work if the current subtarget mode does not apply to them.
In addition, MipsAsmPrinter needs to be reset on a function basis.
The pass BasicTargetTransformInfo is substituted with a null pass since the
pass is immutable and really needs to be a function pass for it to be
used with changing subtargets. This will be fixed in a follow on patch.
llvm-svn: 179118
