Hook up the TableGen lowering for simple pseudo instructions for ARM and
use it for a subset of the many pseudos the backend has as proof of concept.
More conversions to come.
llvm-svn: 134705
This allows the (many) pseudo-instructions we have that map onto a single
real instruction to have their expansion during MC lowering handled
automatically instead of the current cumbersome manual expansion required.
These sorts of pseudos are common when an instruction is used in situations
that require different MachineInstr flags (isTerminator, isBranch, et. al.)
than the generic instruction description has. For example, using a move
to the PC to implement a branch.
llvm-svn: 134704
Previously, despite the names 'enqueue' and 'dequeue', it behaved as
a stack and visited blocks in a LIFO fashion. This interacts badly with
extremely broad CFGs *inside* of a loop (such as a large switch inside
a state machine) where every block updates a different variable.
When encountering such a CFG, the checker visited blocks in essentially
a "depth first" order due to the stack-like behavior of the work list.
Combined with each block updating a different variable, the saturation
logic of the checker caused it to re-traverse blocks [1,N-1] of the
broad CFG inside the loop after traversing block N. These re-traversals
were to propagate the variable values derived from block N. Assuming
approximately the same number of variables as inner blocks exist, the
end result is O(N^2) updates. By making this a queue, we also make the
traversal essentially "breadth-first" across each of the N inner blocks
of the loop. Then all of this state is propagated around to all N inner
blocks of the loop. The result is O(N) updates.
The truth is in the numbers:
Before, gcc.c: 96409 block visits (max: 61546, avg: 591)
After, gcc.c: 69958 block visits (max: 33090, avg: 429)
Before, PR10183: 2540494 block vists (max: 2536495, avg: 37360)
After, PR10183: 137803 block visits (max: 134406, avg: 2026)
The nearly 20x reduction in work for PR10183 corresponds to a roughly
100x speedup in compile time.
I've tested it on all the code I can get my hands on, and I've seen no
slowdowns due to this change. Where I've collected stats, the ammount of
work done is on average less. I'll also commit shortly some synthetic
test cases useful in analyzing the performance of CFG-based warnings.
Submitting this based on Doug's feedback that post-commit review should
be good. Ted, please review! Hopefully this helps compile times until
then.
llvm-svn: 134697
We have to do this in DAGBuilder instead of DAGCombiner, because the exact bit is lost after building.
struct foo { char x[24]; };
long bar(struct foo *a, struct foo *b) { return a-b; }
is now compiled into
movl 4(%esp), %eax
subl 8(%esp), %eax
sarl $3, %eax
imull $-1431655765, %eax, %eax
instead of
movl 4(%esp), %eax
subl 8(%esp), %eax
movl $715827883, %ecx
imull %ecx
movl %edx, %eax
shrl $31, %eax
sarl $2, %edx
addl %eax, %edx
movl %edx, %eax
llvm-svn: 134695
change.
Previously clang was passing the following feature strings to the ARM backend
when CPU is cortex-a8: +neon,-vfp2,-vfp3
This used to work because -vfp2,-vfp3 had no effect after +neon. Now that the
features are controlled by individual bits (with implied hierarchy), the net
effect is all three features will be turned off.
llvm-svn: 134691
the one process we're interested in, instead of fetching all
of them and only keeping one.
(the old implementation made sense when we were doing the
initial find-this-process-by-pid-or-name by looking through
all the kinfo_procs.)
llvm-svn: 134686
loaded. It locks onto *-apple-darwin binaries where the binary has
a "__KLD" segment. Soon I will modify the lldb_private::ObjectFile
class to return an executable type which will be an enum with values
something like:
eObjectFileTypeUserExectable,
eObjectFileTypeUserSharedLibrary,
eObjectFileTypeKernelExectable,
eObjectFileTypeKernelSharedLibrary,
eObjectFileTypeObjectFile,
eObjectFileTypeCoreFile
But for now we look at the section since a user and kernel mach-o
executable have the same mach-o file type.
llvm-svn: 134682
new GetValueForExpressionPath() method in ValueObject to navigate expression paths in a more bitfield vs slices aware way
changes to the varformats.html document (WIP)
llvm-svn: 134679
- Each target asm parser now creates its own MCSubtatgetInfo (if needed).
- Changed AssemblerPredicate to take subtarget features which tablegen uses
to generate asm matcher subtarget feature queries. e.g.
"ModeThumb,FeatureThumb2" is translated to
"(Bits & ModeThumb) != 0 && (Bits & FeatureThumb2) != 0".
llvm-svn: 134678
argument expansion to use the macro argument source locations as well.
Add a few tests to exercise this. There is still a bit more work needed
here though.
llvm-svn: 134674
pointers. Some of the spots are obviously initialized
later, but it's better just to NULL the pointers out
at initialization to make the code more robust when
exposed to later changes.
llvm-svn: 134670
It was testing a linear scan feature:
Test if linearscan is unfavoring registers for allocation to allow
more reuse of reloads from stack slots.
The greedy register allocator doesn't access any stack slots in this
function, so the linear scan feature was not being tested.
llvm-svn: 134666
instantiation and improve diagnostics which are stem from macro
arguments to trace the argument itself back through the layers of macro
expansion.
This requires some tricky handling of the source locations, as the
argument appears to be expanded in the opposite direction from the
surrounding macro. This patch provides helper routines that encapsulate
the logic and explain the reasoning behind how we step through macros
during diagnostic printing.
This fixes the rest of the test cases originially in PR9279, and later
split out into PR10214 and PR10215.
There is still some more work we can do here to improve the macro
backtrace, but those will follow as separate patches.
llvm-svn: 134660
Jim Grosbach