Commit Graph

15 Commits

Author SHA1 Message Date
Haicheng Wu 69ba0613f2 [GlobalMerge] Exit early if only one global is to be merged
To save some compilation time and prevent some unnecessary changes.

Differential Revision: https://reviews.llvm.org/D46640

llvm-svn: 332813
2018-05-19 18:00:02 +00:00
Matthias Braun 7c91336efe ARM: Do not use llc -march in tests.
`llc -march` is problematic because it only switches the target
architecture, but leaves the operating system unchanged. This
occasionally leads to indeterministic tests because the OS from
LLVM_DEFAULT_TARGET_TRIPLE is used.

However we can simply always use `llc -mtriple` instead. This changes
all the tests to do this to avoid people using -march when they copy and
paste parts of tests.

See also the discussion in https://reviews.llvm.org/D35287

llvm-svn: 309755
2017-08-01 22:20:49 +00:00
David Majnemer 7fddeccb8b Move the personality function from LandingPadInst to Function
The personality routine currently lives in the LandingPadInst.

This isn't desirable because:
- All LandingPadInsts in the same function must have the same
  personality routine.  This means that each LandingPadInst beyond the
  first has an operand which produces no additional information.

- There is ongoing work to introduce EH IR constructs other than
  LandingPadInst.  Moving the personality routine off of any one
  particular Instruction and onto the parent function seems a lot better
  than have N different places a personality function can sneak onto an
  exceptional function.

Differential Revision: http://reviews.llvm.org/D10429

llvm-svn: 239940
2015-06-17 20:52:32 +00:00
Sunil Srivastava d79dfcbc37 Changed renaming of local symbols by inserting a dot vefore the numeric suffix.
One code change and several test changes to match that
details in http://reviews.llvm.org/D9481

llvm-svn: 237150
2015-05-12 16:47:30 +00:00
Ahmed Bougacha 279e3ee954 [GlobalMerge] Look at uses to create smaller global sets.
Instead of merging everything together, look at the users of
GlobalVariables, and try to group them by function, to create
sets of globals used "together".

Using that information, a less-aggressive alternative is to keep merging
everything together *except* globals that are only ever used alone, that
is, those for which it's clearly non-profitable to merge with others.

In my testing, grouping by Function is too aggressive, but grouping by
BasicBlock is too conservative.  Anything in-between isn't trivially
available, so stick with Function grouping for now.

cl::opts are added for testing; both enabled by default.

A few of the testcases aren't testing the merging proper, but just
various edge cases when merging does occur.  Update them to use the
previous grouping behavior. Also, one of the tests is unrelated to
GlobalMerge; change it accordingly.
While there, switch to r234666' flags rather than the brutal -O3.

Differential Revision: http://reviews.llvm.org/D8070

llvm-svn: 235249
2015-04-18 01:21:58 +00:00
Ahmed Bougacha d1655cb1c0 [AArch64, ARM] Enable GlobalMerge with -O3 rather than -O1.
The pass used to be enabled by default with CodeGenOpt::Less (-O1).
This is too aggressive, considering the pass indiscriminately merges
all globals together.

Currently, performance doesn't always improve, and, on code that uses
few globals (e.g., the odd file- or function- static), more often than
not is degraded by the optimization.  Lengthy discussion can be found
on llvmdev (AArch64-focused;  ARM has similar problems):
  http://lists.cs.uiuc.edu/pipermail/llvmdev/2015-February/082800.html
Also, it makes tooling and debuggers less useful when dealing with
globals and data sections.

GlobalMerge needs to better identify those cases that benefit, and this
will be done separately.  In the meantime, move the pass to run with
-O3 rather than -O1, on both ARM and AArch64.

llvm-svn: 233024
2015-03-23 21:17:36 +00:00
Quentin Colombet 8fc340976d Extend global merge pass to optionally consider global constant variables.
Also add some checks to not merge globals used within landing pad instructions or marked as "used".

llvm-svn: 177331
2013-03-18 22:30:07 +00:00
Eli Friedman 6cff9df298 Make GlobalMerge honor the preferred alignment on globals without an explicitly specified alignment.
<rdar://problem/10497732>.

llvm-svn: 145523
2011-11-30 21:54:15 +00:00
Devang Patel abc77347a7 Enable GlobalMerge on darwin.
llvm-svn: 128183
2011-03-23 23:34:19 +00:00
Devang Patel 906df92d5c XFAIL for all. These tests are darwin specific anyway.
llvm-svn: 127022
2011-03-04 19:38:10 +00:00
Devang Patel a0d73fd65e Disable ARMGlobalMerge on darwin. The debugger is not yet able to extract individual variable's info from merged global.
llvm-svn: 127019
2011-03-04 19:11:05 +00:00
Bob Wilson 881b45ccdf Change ARMGlobalMerge to keep BSS globals in separate pools.
This completes the fixes for Radar 8673120.

llvm-svn: 119566
2010-11-17 21:25:39 +00:00
Bob Wilson 4c8ab19c22 Fix ARMGlobalMerge pass to check if globals are entirely within range.
It is generally not sufficient to check if the starting offset is in range
of the maximum offset that can be efficiently used for the target.

llvm-svn: 119565
2010-11-17 21:25:36 +00:00
Bob Wilson 59182fb4b5 Change the symbol for merged globals from "merged" to "_MergedGlobals".
This makes it more clear that the symbol is an internal, compiler-generated
name and gives a little more description about its contents.

llvm-svn: 119564
2010-11-17 21:25:33 +00:00
Bob Wilson f796d4b469 Fix the ARMGlobalMerge pass to look at variable sizes instead of pointer sizes.
It was mistakenly looking at the pointer type when checking for the size of
global variables.  This is a partial fix for Radar 8673120.

llvm-svn: 119563
2010-11-17 21:25:27 +00:00