Commit Graph

208 Commits

Author SHA1 Message Date
Arnaud A. de Grandmaison de5ff26865 No need for those tests to go thru llvm-as and/or llvm-dis.
opt can handle them by itself.

llvm-svn: 209689
2014-05-27 22:03:28 +00:00
Bill Wendling 90dd90afcb Don't eliminate a partially redundant load if it's in a landing pad.
A landing pad can be jumped to only by the unwind edge of an invoke
instruction. If we eliminate a partially redundant load in a landing pad, it
will create a basic block that violates this constraint. It then leads to other
problems down the line if it tries to merge that basic block with the landing
pad. Avoid this by not eliminating the load in a landing pad.

PR17621

llvm-svn: 193064
2013-10-21 04:09:17 +00:00
Bill Wendling 4fea22c63b Perform an intelligent splice of the predecessor with the single successor.
If the predecessor's being spliced into a landing pad, then we need the PHIs to
come first and the rest of the predecessor's code to come *after* the landing
pad instruction.

llvm-svn: 193035
2013-10-19 11:27:12 +00:00
Manman Ren 0ed04fc9ab TBAA: handle scalar TBAA format and struct-path aware TBAA format.
Remove the command line argument "struct-path-tbaa" since we should not depend
on command line argument to decide which format the IR file is using. Instead,
we check the first operand of the tbaa tag node, if it is a MDNode, we treat
it as struct-path aware TBAA format, otherwise, we treat it as scalar TBAA
format.

When clang starts to use struct-path aware TBAA format no matter whether
struct-path-tbaa is no, and we can auto-upgrade existing bc files, the support
for scalar TBAA format can be dropped.

Existing testing cases are updated to use the struct-path aware TBAA format.

llvm-svn: 191538
2013-09-27 18:34:27 +00:00
Daniel Dunbar 9efbedfd35 [tests] Cleanup initialization of test suffixes.
- Instead of setting the suffixes in a bunch of places, just set one master
   list in the top-level config. We now only modify the suffix list in a few
   suites that have one particular unique suffix (.ml, .mc, .yaml, .td, .py).

 - Aside from removing the need for a bunch of lit.local.cfg files, this enables
   4 tests that were inadvertently being skipped (one in
   Transforms/BranchFolding, a .s file each in DebugInfo/AArch64 and
   CodeGen/PowerPC, and one in CodeGen/SI which is now failing and has been
   XFAILED).

 - This commit also fixes a bunch of config files to use config.root instead of
   older copy-pasted code.

llvm-svn: 188513
2013-08-16 00:37:11 +00:00
Benjamin Kramer 6a4976d3e0 JumpThreading: Turn a select instruction into branching if it allows to thread one half of the select.
This is a common pattern coming out of simplifycfg generating gross code.

a:                                       ; preds = %entry
  %sel = select i1 %cmp1, double %add, double 0.000000e+00
  br label %b

b:
  %cond5 = phi double [ %sel, %a ], [ %sub, %entry ]
  %cmp6 = fcmp oeq double %cond5, 0.000000e+00
  br i1 %cmp6, label %if.then, label %if.end

becomes

a:
  br i1 %cmp1, label %b, label %if.then

b:
  %cond5 = phi double [ %sub, %entry ], [ %add, %a ]
  %cmp6 = fcmp oeq double %cond5, 0.000000e+00
  br i1 %cmp6, label %if.then, label %if.end

Skipping block b completely if possible.

llvm-svn: 187880
2013-08-07 10:29:38 +00:00
Stephen Lin c1c7a1309c Update Transforms tests to use CHECK-LABEL for easier debugging. No functionality change.
This update was done with the following bash script:

  find test/Transforms -name "*.ll" | \
  while read NAME; do
    echo "$NAME"
    if ! grep -q "^; *RUN: *llc" $NAME; then
      TEMP=`mktemp -t temp`
      cp $NAME $TEMP
      sed -n "s/^define [^@]*@\([A-Za-z0-9_]*\)(.*$/\1/p" < $NAME | \
      while read FUNC; do
        sed -i '' "s/;\(.*\)\([A-Za-z0-9_]*\):\( *\)@$FUNC\([( ]*\)\$/;\1\2-LABEL:\3@$FUNC(/g" $TEMP
      done
      mv $TEMP $NAME
    fi
  done

llvm-svn: 186268
2013-07-14 01:42:54 +00:00
Manman Ren 1a5ff287fd TBAA: remove !tbaa from testing cases if not used.
This will make it easier to turn on struct-path aware TBAA since the metadata
format will change.

llvm-svn: 180796
2013-04-30 17:52:57 +00:00
Bill Wendling a032374ea0 Use references to attribute groups on the call/invoke instructions.
Listing all of the attributes for the callee of a call/invoke instruction is way
too much and makes the IR unreadable. Use references to attributes instead.

llvm-svn: 175877
2013-02-22 09:09:42 +00:00
Dmitri Gribenko d7beca87f5 Tests: rewrite 'opt ... %s' to 'opt ... < %s' so that opt does not emit a ModuleID
This is done to avoid odd test failures, like the one fixed in r171243.

My previous regex was not good enough to find these.

llvm-svn: 171343
2013-01-01 13:57:25 +00:00
Dmitri Gribenko 56bf2e1830 Tests: rewrite 'opt ... %s' to 'opt ... < %s' so that opt does not emit a ModuleID
This is done to avoid odd test failures, like the one fixed in r171243.

llvm-svn: 171250
2012-12-30 02:33:22 +00:00
Dmitri Gribenko b137c9e551 Tests: rewrite 'opt ... %s' to 'opt ... < %s' so that opt does not emit a ModuleID
This is done to avoid odd test failures, like the one fixed in r171243.

llvm-svn: 171246
2012-12-30 01:28:40 +00:00
James Molloy 4f6fb953a7 Add a new attribute, 'noduplicate'. If a function contains a noduplicate call, the call cannot be duplicated - Jump threading, loop unrolling, loop unswitching, and loop rotation are inhibited if they would duplicate the call.
Similarly inlining of the function is inhibited, if that would duplicate the call (in particular inlining is still allowed when there is only one callsite and the function has internal linkage).

llvm-svn: 170704
2012-12-20 16:04:27 +00:00
Chandler Carruth d5639ff80f Add a test case for PR14233.
llvm-svn: 167224
2012-11-01 10:26:36 +00:00
Manman Ren f3fedb6935 JumpThreading: when default destination is the destination of some cases in a
switch, make sure we include the value for the cases when calculating edge
value from switch to the default destination.

rdar://12241132

llvm-svn: 163270
2012-09-05 23:45:58 +00:00
Richard Osborne 0ab2b0df82 Fix assertion in jump threading (PR13405).
GetBestDestForJumpOnUndef() assumes there is at least 1 successor, which isn't
true if the block ends in an indirect branch with no successors. Fix this by
bailing out earlier in this case.

llvm-svn: 160546
2012-07-20 10:36:17 +00:00
Chandler Carruth ff123d5c63 Fix the remaining TCL-style quotes found in the testsuite. This is
another mechanical change accomplished though the power of terrible Perl
scripts.

I have manually switched some "s to 's to make escaping simpler.

While I started this to fix tests that aren't run in all configurations,
the massive number of tests is due to a really frustrating fragility of
our testing infrastructure: things like 'grep -v', 'not grep', and
'expected failures' can mask broken tests all too easily.

Essentially, I'm deeply disturbed that I can change the testsuite so
radically without causing any change in results for most platforms. =/

llvm-svn: 159547
2012-07-02 19:09:46 +00:00
Chandler Carruth a5a29f970e Convert all tests using TCL-style quoting to use shell-style quoting.
This was done through the aid of a terrible Perl creation. I will not
paste any of the horrors here. Suffice to say, it require multiple
staged rounds of replacements, state carried between, and a few
nested-construct-parsing hacks that I'm not proud of. It happens, by
luck, to be able to deal with all the TCL-quoting patterns in evidence
in the LLVM test suite.

If anyone is maintaining large out-of-tree test trees, feel free to poke
me and I'll send you the steps I used to convert things, as well as
answer any painful questions etc. IRC works best for this type of thing
I find.

Once converted, switch the LLVM lit config to use ShTests the same as
Clang. In addition to being able to delete large amounts of Python code
from 'lit', this will also simplify the entire test suite and some of
lit's architecture.

Finally, the test suite runs 33% faster on Linux now. ;]
For my 16-hardware-thread (2x 4-core xeon e5520): 36s -> 24s

llvm-svn: 159525
2012-07-02 12:47:22 +00:00
Joel Jones 7f04344b8b formatting change: strip debug info from test
llvm-svn: 156551
2012-05-10 16:55:31 +00:00
Joel Jones 3d90a9ae65 Fix a problem with incomplete equality testing of PHINodes in
Instruction::IsIdenticalToWhenDefined.

This manifested itself when inlining two calls to the same function.  The 
inlined function had a switch statement that returned one of a set of 
global variables.  Without this modification, the two phi instructions that 
chose values from the branches of the switch instruction inlined from the 
callee were considered equivalent and jump-threading replaced a load for the 
first switch value with a phi selecting from the second switch, thereby 
producing incorrect code.

This patch has been tested with "make check-all", "lnt runteste nt", and 
llvm self-hosted, and on the original program that had this problem, 
wireshark.

<rdar://problem/11025519>

llvm-svn: 156548
2012-05-10 15:59:41 +00:00
Chris Lattner 87fa77bd8a enhance jump threading to preserve TBAA information when PRE'ing loads,
fixing rdar://11039258, an issue that came up when inspecting clang's 
bootstrapped codegen.

llvm-svn: 152635
2012-03-13 18:07:41 +00:00
Eli Bendersky 924f9a671d Replace all instances of dg.exp file with lit.local.cfg, since all tests are run with LIT now and now Dejagnu. dg.exp is no longer needed.
Patch reviewed by Daniel Dunbar. It will be followed by additional cleanup patches.

llvm-svn: 150664
2012-02-16 06:28:33 +00:00
Chris Lattner 6a144a2227 Upgrade syntax of tests using volatile instructions to use 'load volatile' instead of 'volatile load', which is archaic.
llvm-svn: 145171
2011-11-27 06:54:59 +00:00
Eli Friedman 02e737b08e Move "atomic" and "volatile" designations on instructions after the opcode
of the instruction.

Note that this change affects the existing non-atomic load and store
instructions; the parser now accepts both forms, and the change is noted
in the release notes.

llvm-svn: 137527
2011-08-12 22:50:01 +00:00
Chris Lattner 59345c8b65 remove asmparser support for the old getresult instruction, which has been subsumed by extractvalue.
llvm-svn: 133247
2011-06-17 06:57:15 +00:00
Owen Anderson 92651ec374 Fix an infinite alternation in JumpThreading where two transforms would repeatedly undo each other. The solution is to perform more aggressive constant folding to make one of the edges just folded away rather than trying to thread it.
Fixes <rdar://problem/9284786>.

Discovered with CSmith.

llvm-svn: 129538
2011-04-14 21:35:50 +00:00
Eli Friedman 17bf4922c9 PR9446: RecursivelyDeleteTriviallyDeadInstructions can delete the instruction
after the given instruction; make sure to handle that case correctly.
(It's difficult to trigger; the included testcase involves a dead 
block, but I don't think that's a requirement.) 

While I'm here, get rid of the unnecessary warning about
SimplifyInstructionsInBlock, since it should work correctly as far as I know.

llvm-svn: 128782
2011-04-02 22:45:17 +00:00
Duncan Sands 7dc3d47c34 Fix PR9331. Simplified version of a patch by Jakub Staszak.
llvm-svn: 127243
2011-03-08 12:39:03 +00:00
Chris Lattner 1a924e770a prevent jump threading from merging blocks when their address is
taken (and used!).  This prevents merging the blocks (invalidating
the block addresses) in a case like this:

#define _THIS_IP_  ({ __label__ __here; __here: (unsigned long)&&__here; })

void foo() {
  printf("%p\n", _THIS_IP_);
  printf("%p\n", _THIS_IP_);
  printf("%p\n", _THIS_IP_);
}

which fixes PR4151.

llvm-svn: 125829
2011-02-18 04:43:06 +00:00
Nick Lewycky ac0b62c277 Tolerate degenerate phi nodes that can occur in the middle of optimization
passes. Fixes PR9112. Patch by Jakub Staszak!

llvm-svn: 125319
2011-02-10 23:54:10 +00:00
Evan Cheng d983eba7dc Re-apply r124518 with fix. Watch out for invalidated iterator.
llvm-svn: 124526
2011-01-29 04:46:23 +00:00
Evan Cheng 65b8ccf6ac Revert r124518. It broke Linux self-host.
llvm-svn: 124522
2011-01-29 02:43:04 +00:00
Evan Cheng d4eff31476 Re-commit r124462 with fixes. Tail recursion elim will now dup ret into unconditional predecessor to enable TCE on demand.
llvm-svn: 124518
2011-01-29 01:29:26 +00:00
Evan Cheng aaa9606b2f Revert r124462. There are a few big regressions that I need to fix first.
llvm-svn: 124478
2011-01-28 07:12:38 +00:00
Evan Cheng 417fca86c4 - Stop simplifycfg from duplicating "ret" instructions into unconditional
branches. PR8575, rdar://5134905, rdar://8911460.
- Allow codegen tail duplication to dup small return blocks after register
  allocation is done.

llvm-svn: 124462
2011-01-28 02:19:21 +00:00
Frits van Bommel 3d1803495e Teach jump threading to "look through" a select when the branch direction of a terminator depends on it.
When it sees a promising select it now tries to figure out whether the condition of the select is known in any of the predecessors and if so it maps the operands appropriately.

llvm-svn: 121859
2010-12-15 09:51:20 +00:00
Frits van Bommel d9df6eaa9c Implement jump threading of 'indirectbr' by keeping track of whether we're looking for ConstantInt*s or BlockAddress*s.
llvm-svn: 121066
2010-12-06 23:36:56 +00:00
Owen Anderson 99c985c37d Fix PR8247: JumpThreading can cause a block to become unreachable while still having predecessor, if it is part of a self-loop.
Because of this, we cannot use the Simplify* APIs, as they can assert-fail on unreachable code.  Since it's not easy to determine
if a given threading will cause a block to become unreachable, simply defer simplifying simplification to later InstCombine and/or
DCE passes.

llvm-svn: 115082
2010-09-29 20:34:41 +00:00
Owen Anderson f6fe577e88 Remove dead option from tests.
llvm-svn: 113855
2010-09-14 21:03:40 +00:00
Owen Anderson a5e6b3eca4 Merge 2010-08-31-InfiniteRecursion.ll into crash.ll.
llvm-svn: 112635
2010-08-31 20:27:17 +00:00
Owen Anderson 799a08ae48 Add a test for the duplicated-conditional situation illutrated by PR5652.
llvm-svn: 112621
2010-08-31 18:49:12 +00:00
Owen Anderson 3931c85956 Manually reduce this testcase.
llvm-svn: 112615
2010-08-31 18:16:29 +00:00
Owen Anderson ada0623725 Add a micro-test for the transforms I added to JumpThreading.
I have not been able to find a way to test each in isolation, for a few reasons:
1) The ability to look-through non-i1 BinaryOperator's requires the ability to look through non-constant
   ICmps in order for it to ever trigger.
2) The ability to do LVI-powered PHI value determination only matters in cases that ProcessBranchOnPHI
   can't handle.  Since it already handles all the cases without other instructions in the def-use chain
   between the PHI and the branch, it requires the ability to look through ICmps and/or BinaryOperators
   as well.

llvm-svn: 112611
2010-08-31 17:59:07 +00:00
Owen Anderson 3997a07fb9 More Chris-inspired JumpThreading fixes: use ConstantExpr to correctly constant-fold undef, and be more careful with its return value.
This actually exposed an infinite recursion bug in ComputeValueKnownInPredecessors which theoretically already existed (in JumpThreading's
handling of and/or of i1's), but never manifested before.  This patch adds a tracking set to prevent this case.

llvm-svn: 112589
2010-08-31 07:36:34 +00:00
Owen Anderson 6ebbd92380 Use LVI to eliminate conditional branches where we've tested a related condition previously. Update tests for this change.
This fixes PR5652.

llvm-svn: 112270
2010-08-27 17:12:29 +00:00
Owen Anderson bd2ecc7e68 Make JumpThreading smart enough to properly thread StrSwitch when it's compiled with clang++.
llvm-svn: 112198
2010-08-26 17:40:24 +00:00
Owen Anderson 4afea9e3c6 In the default address space, any GEP off of null results in a trap value if you try to load it. Thus,
any load in the default address space that completes implies that the base value that it GEP'd from
was not null.

llvm-svn: 112015
2010-08-25 01:16:47 +00:00
Chris Lattner 3c603024bb Fix PR7755: knowing something about an inval for a pred
from the LHS should disable reconsidering that pred on the
RHS.  However, knowing something about the pred on the RHS
shouldn't disable subsequent additions on the RHS from
happening.

llvm-svn: 111349
2010-08-18 03:14:36 +00:00
Owen Anderson bb4c4b59a4 Fix a test with malformed IR. Not sure why this didn't fail before.
llvm-svn: 109422
2010-07-26 18:44:56 +00:00
Chris Lattner 19eff2a9f6 Fix PR7647, handling the case when 'To' ends up being
mutated by recursive simplification.  This also enhances
ReplaceAndSimplifyAllUses to actually do a real RAUW
at the end of it, which updates any value handles
pointing to "From" to start pointing to "To".  This
seems useful for debug info and random other VH users.

llvm-svn: 108415
2010-07-15 06:36:08 +00:00
Chris Lattner bbc25ff5cc if jump threading is able to infer interesting values on both
the LHS and RHS of an and/or instruction, don't multiply add
known predecessor values.  This fixes the crash on testcase
from PR7498

llvm-svn: 108114
2010-07-12 00:47:34 +00:00
Chris Lattner 329ea064ed jump threading can't split a critical edge from an indirectbr. This
fixes PR7356.

llvm-svn: 105950
2010-06-14 19:45:43 +00:00
Chris Lattner 9ae28b141f fix PR6743, a case where we'd delete an instruction before using it
in some cases.

llvm-svn: 100937
2010-04-10 18:26:57 +00:00
Chris Lattner 6fbfe5897c fix PR6305 by handling BlockAddress in a helper function
called by jump threading.

llvm-svn: 96263
2010-02-15 20:47:49 +00:00
Chris Lattner d924f63692 Make jump threading honor x|undef -> true and x&undef -> false,
instead of considering x|undef -> x, which may not be true.

llvm-svn: 95850
2010-02-11 04:40:44 +00:00
Chris Lattner 29b15c5cfd third bug from PR6119: the xor dupe extension allows
for arbitrary terminators in predecessors, don't assume
it is a conditional or uncond branch.  The testcase shows
an example where they can happen with switches.

llvm-svn: 94323
2010-01-23 19:21:31 +00:00
Chris Lattner ba2d0b89ff add an early out to ProcessBranchOnXOR to speed it up,
handle the case when we can infer an input to the xor
from all inputs that agree, instead of going into an
infinite loop.  Another part of PR6199

llvm-svn: 94321
2010-01-23 19:16:25 +00:00
Chris Lattner de5ab4860f fix a crash in jump threading, PR6119
llvm-svn: 94319
2010-01-23 18:56:07 +00:00
Chris Lattner 573da8ac90 1) Use the new SimplifyInstructionsInBlock routine instead of the copy
in JT.

2) When cloning blocks for PHI or xor conditions, use
instsimplify to simplify the code as we go.  This allows us to 
squish common cases early in JT which opens up opportunities for
subsequent iterations, and allows it to completely simplify the
testcase.

llvm-svn: 93253
2010-01-12 20:41:47 +00:00
Chris Lattner eb73bdb2e1 Teach jump threading to duplicate small blocks when the branch
condition is a xor with a phi node.  This eliminates nonsense
like this from 176.gcc in several places:

 LBB166_84:
        testl   %eax, %eax
-       setne   %al
-       xorb    %cl, %al
-       notb    %al
-       testb   $1, %al
-       je      LBB166_85
+       je      LBB166_69
+       jmp     LBB166_85

This is rdar://7391699

llvm-svn: 93221
2010-01-12 02:07:17 +00:00
Chris Lattner 6d6f10fe91 fix PR5698
llvm-svn: 90708
2009-12-06 17:17:23 +00:00
Chris Lattner 3c9aca9079 fix PR5640 by tracking whether a block is the header of a loop more
precisely, which prevents us from infinitely peeling the loop.

llvm-svn: 90211
2009-12-01 06:04:43 +00:00
Gabor Greif 13431c6cdf typo
llvm-svn: 86980
2009-11-12 09:44:17 +00:00
Chris Lattner 5f6b8b2bcb use getPredicateOnEdge to fold comparisons through PHI nodes,
which implements GCC PR18046.  This also gets us 360 more
jump threads on 176.gcc.

llvm-svn: 86953
2009-11-12 05:24:05 +00:00
Chris Lattner 380ccbaeaa should not commit when distracted.
llvm-svn: 86929
2009-11-12 02:04:17 +00:00
Chris Lattner e2a63f2798 We now thread some impossible condition information with LVI.
llvm-svn: 86927
2009-11-12 01:55:20 +00:00
Chris Lattner ba45616958 with the new code we can thread non-instruction values. This
allows us to handle the test10 testcase.

llvm-svn: 86924
2009-11-12 01:41:34 +00:00
Chris Lattner b584d1e456 move some stuff into DEBUG's and turn on lazy-value-info for
the basic.ll testcase.

llvm-svn: 86918
2009-11-12 01:22:16 +00:00
Chris Lattner 6e960c8657 oops, didn't mean to commit this, no harm, but add a todoops, didn't mean to commit this, no harm, but add a todoo
llvm-svn: 86768
2009-11-11 00:27:54 +00:00
Chris Lattner 741c94c719 Stub out a new lazy value info pass, which will eventually
vend value constraint information to the optimizer.

llvm-svn: 86767
2009-11-11 00:22:30 +00:00
Chris Lattner 9518fbb54e implement a TODO by teaching jump threading about "xor x, 1".
llvm-svn: 86739
2009-11-10 22:39:16 +00:00
Chris Lattner 80e7e5a429 Make jump threading eliminate blocks that just contain phi nodes,
debug intrinsics, and an unconditional branch when possible.  This
reuses the TryToSimplifyUncondBranchFromEmptyBlock function split
out of simplifycfg.

llvm-svn: 86722
2009-11-10 21:40:01 +00:00
Chris Lattner 38c44ea6b0 make jump threading recursively simplify expressions instead of doing it
just one level deep.  On the testcase we go from getting this:

F1:                                               ; preds = %T2
  %F = and i1 true, %cond                         ; <i1> [#uses=1]
  br i1 %F, label %X, label %Y

to a fully threaded:

F1:                                               ; preds = %T2
  br label %Y


This changes gets us to the point where we're forming (too many) switch 
instructions on doug's strswitch testcase.

llvm-svn: 86646
2009-11-10 01:57:31 +00:00
Chris Lattner 5ff7f5672e reapply 86289, 86278, 86270, 86267, 86266 & 86264 plus a fix
(making pred factoring only happen if threading is guaranteed
to be successful).

This now survives an X86-64 bootstrap of llvm-gcc.

llvm-svn: 86355
2009-11-07 08:05:03 +00:00
Devang Patel 3a42e7ac65 Revert following patches to fix llvmgcc bootstrap.
86289, 86278, 86270, 86267, 86266 & 86264
Chris, please take a look.

llvm-svn: 86321
2009-11-07 01:32:59 +00:00
Chris Lattner a8b9ce3f07 Fix a problem discovered on self host.
llvm-svn: 86278
2009-11-06 19:21:48 +00:00
Chris Lattner 68d2417e05 Extend jump threading to support much more general threading
predicates.  This allows us to jump thread things like:

_ZN12StringSwitchI5ColorE4CaseILj7EEERS1_RAT__KcRKS0_.exit119:
  %tmp1.i24166 = phi i8 [ 1, %bb5.i117 ], [ %tmp1.i24165, %_Z....exit ], [ %tmp1.i24165, %bb4.i114 ] 
  %toBoolnot.i87 = icmp eq i8 %tmp1.i24166, 0     ; <i1> [#uses=1]
  %tmp4.i90 = icmp eq i32 %tmp2.i, 6              ; <i1> [#uses=1]
  %or.cond173 = and i1 %toBoolnot.i87, %tmp4.i90  ; <i1> [#uses=1]
  br i1 %or.cond173, label %bb4.i96, label %_ZN12...

Where it is "obvious" that when coming from %bb5.i117 that the 'and' is always 
false.  This triggers a surprisingly high number of times in the testsuite, 
and gets us closer to generating good code for doug's strswitch testcase.

This also make a bunch of other code in jump threading redundant, I'll rip
out in the next patch.  This survived an enable-checking llvm-gcc bootstrap.

llvm-svn: 86264
2009-11-06 18:15:14 +00:00
Chris Lattner 046dff7acf merge a few crash tests into crash.ll
llvm-svn: 86119
2009-11-05 05:57:34 +00:00
Dan Gohman a484d17ec5 Make these tests more interesting by using
-verify-dom-info and -verify-loop-info, which enable additional
(expensive) consistency checks.

llvm-svn: 85017
2009-10-24 23:23:04 +00:00
Chris Lattner 7f903681ac alternate fix for PR5258 which avoids worklist problems, with reduced testcase.
llvm-svn: 84667
2009-10-20 20:27:49 +00:00
Torok Edwin cf10ec951d Fix PR5258, jump-threading creating invalid PHIs.
When an incoming value for a PHI is updated, we must also updated all other
incoming values for the same BB to match, otherwise we create invalid PHIs.

llvm-svn: 84638
2009-10-20 15:42:00 +00:00
Chris Lattner 85c85c5e04 when folding duplicate conditions, delete the
now-probably-dead instruction tree feeding it.

llvm-svn: 83778
2009-10-11 18:39:58 +00:00
Chris Lattner 97b1405207 implement a transformation in jump threading that is currently
done by condprop, but do it in a much more general form.  The
basic idea is that we can do a limited form of tail duplication
in the case when we have a branch on a phi.  Moving the branch
up in to the predecessor block makes instruction selection
much easier and encourages chained jump threadings.

llvm-svn: 83759
2009-10-11 07:24:57 +00:00
Chris Lattner 4140d8bd5c another testcase jump threading shouldn't crash on.
llvm-svn: 83758
2009-10-11 07:11:11 +00:00
Chris Lattner ece16f2335 rename a file, remove a poorly reduced testcase.
llvm-svn: 83757
2009-10-11 07:10:28 +00:00
Chris Lattner f99a74e24b make jump threading on a phi with undef inputs happen.
llvm-svn: 83754
2009-10-11 04:18:15 +00:00
Chris Lattner 8d186bfafb merge two tests.
llvm-svn: 83751
2009-10-11 03:55:30 +00:00
Chris Lattner 041c1dca8b simplify some run lines, convert a test to filecheck.
llvm-svn: 83750
2009-10-11 03:54:21 +00:00
Dan Gohman 1880092722 Change tests from "opt %s" to "opt < %s" so that opt doesn't see the
input filename so that opt doesn't print the input filename in the
output so that grep lines in the tests don't unintentionally match
strings in the input filename.

llvm-svn: 81537
2009-09-11 18:01:28 +00:00
Dan Gohman c8054d90fb Eliminate more uses of llvm-as and llvm-dis.
llvm-svn: 81293
2009-09-09 00:09:15 +00:00
Dan Gohman 72a13d2476 Use opt -S instead of piping bitcode output through llvm-dis.
llvm-svn: 81257
2009-09-08 22:34:10 +00:00
Dan Gohman 9737a63ed8 Change these tests to feed the assembly files to opt directly, instead
of using llvm-as, now that opt supports this.

llvm-svn: 81226
2009-09-08 16:50:01 +00:00
Chris Lattner d0a363e03b make jump threading handle lexically identical compare instructions
as if they were multiple uses of the same instruction.  This interacts
well with the existing loadpre that j-t does to open up many new jump
threads earlier.

llvm-svn: 73768
2009-06-19 16:27:56 +00:00
Nick Lewycky 77585a24ac Teach jump threading to look at comparisons between phi nodes and non-constants.
llvm-svn: 73755
2009-06-19 04:56:29 +00:00
Chris Lattner d579cb1167 * Sink 4 duplicates of edge threading validity checks and DOUT prints into
ThreadEdge directly.  This shares the code, but is just a refactoring.
* Make JumpThreading compute the set of loop headers and avoid threading
  across them.  This prevents jump threading from forming irreducible 
  loops (goodness) but also prevents it from threading in other cases that
  are beneficial (see the comment above FindFunctionBackedges).

llvm-svn: 70820
2009-05-04 02:28:08 +00:00
Chris Lattner 6f34e317e9 Fix PR3353, infinitely jump threading an infinite loop make from switches.
llvm-svn: 62529
2009-01-19 21:20:34 +00:00
Chris Lattner 482eb70a10 Fix PR3298, a crash in Jump Threading. Apparently even
jump threading can have bugs, who knew? ;-)

llvm-svn: 61983
2009-01-09 06:08:12 +00:00
Chris Lattner 350fc5721d testcase for br undef folding.
llvm-svn: 60471
2008-12-03 07:48:27 +00:00
Chris Lattner 595c7279bd Teach jump threading some more simple tricks:
1) have it fold "br undef", which does occur with
   surprising frequency as jump threading iterates.
2) teach j-t to delete dead blocks.  This removes the successor
   edges, reducing the in-edges of other blocks, allowing 
   recursive simplification.
3) Fold things like:
     br COND, BBX, BBY
  BBX:
     br COND, BBZ, BBW

   which also happens because jump threading iterates.

llvm-svn: 60470
2008-12-03 07:48:08 +00:00
Chris Lattner 8a172daa55 don't call MergeBasicBlockIntoOnlyPred on a block whose only
predecessor is itself.  This doesn't make sense, and this is
a dead infinite loop anyway.

llvm-svn: 60210
2008-11-28 19:54:49 +00:00
Chris Lattner 5dfbfcd80d Fix PR3138: if we merge the entry block into another block, make sure to
move the other block back up into the entry position!

llvm-svn: 60179
2008-11-27 19:25:19 +00:00
Chris Lattner 98d89d1b1b Make jump threading substantially more powerful, in the following ways:
1. Make it fold blocks separated by an unconditional branch.  This enables
   jump threading to see a broader scope.
2. Make jump threading able to eliminate locally redundant loads when they
   feed the branch condition of a block.  This frequently occurs due to
   reg2mem running.
3. Make jump threading able to eliminate *partially redundant* loads when
   they feed the branch condition of a block.  This is common in code with
   lots of loads and stores like C++ code and 255.vortex.

This implements thread-loads.ll and rdar://6402033.

Per the fixme's, several pieces of this should be moved into Transforms/Utils.

llvm-svn: 60148
2008-11-27 05:07:53 +00:00
Chris Lattner 8ed8e3d0e6 Fix a crash when threading a block that includes a MRV call result.
DemoteRegToStack doesn't work with MRVs yet, because it relies on the
ability to load/store things.

This fixes PR2285.

llvm-svn: 50667
2008-05-05 20:21:22 +00:00
Chris Lattner f7de528463 Don't infininitely thread branches when a threaded edge
goes back to the block, e.g.:

  Threading edge through bool from 'bb37.us.thread3829' to 'bb37.us' with cost: 1, across block:

bb37.us:		; preds = %bb37.us.thread3829, %bb37.us, %bb33
	%D1361.1.us = phi i32 [ %tmp36, %bb33 ], [ %D1361.1.us, %bb37.us ], [ 0, %bb37.us.thread3829 ]		; <i32> [#uses=2]
	%tmp39.us = icmp eq i32 %D1361.1.us, 0		; <i1> [#uses=1]
	br i1 %tmp39.us, label %bb37.us, label %bb42.us

llvm-svn: 50251
2008-04-25 04:12:29 +00:00
Chris Lattner 37e9c187b0 Start doing the significantly useful part of jump threading: handle cases
where a comparison has a phi input and that phi is a constant.  For example,
stuff like:

  Threading edge through bool from 'bb2149' to 'bb2231' with cost: 1, across block:
bb2237:		; preds = %bb2231, %bb2149
	%tmp2328.rle = phi i32 [ %tmp2232, %bb2231 ], [ %tmp2232439, %bb2149 ]		; <i32> [#uses=2]
	%done.0 = phi i32 [ %done.2, %bb2231 ], [ 0, %bb2149 ]		; <i32> [#uses=1]
	%tmp2239 = icmp eq i32 %done.0, 0		; <i1> [#uses=1]
	br i1 %tmp2239, label %bb2231, label %bb2327

or

bb38.i298:		; preds = %bb33.i295, %bb1693
	%tmp39.i296.rle = phi %struct.ibox* [ null, %bb1693 ], [ %tmp39.i296.rle1109, %bb33.i295 ]		; <%struct.ibox*> [#uses=2]
	%minspan.1.i291.reg2mem.1 = phi i32 [ 32000, %bb1693 ], [ %minspan.0.i288, %bb33.i295 ]		; <i32> [#uses=1]
	%tmp40.i297 = icmp eq %struct.ibox* %tmp39.i296.rle, null		; <i1> [#uses=1]
	br i1 %tmp40.i297, label %implfeeds.exit311, label %bb43.i301

This triggers thousands of times in spec.

llvm-svn: 50110
2008-04-22 21:40:39 +00:00
Chris Lattner d5425e8f8d Dig through multiple levels of AND to thread jumps if needed.
llvm-svn: 50106
2008-04-22 20:46:09 +00:00
Chris Lattner 3df4c15dc7 Teach jump threading to thread through blocks like:
br (and X, phi(Y, Z, false)), label L1, label L2

This triggers once on 252.eon and 6 times on 176.gcc.  Blocks 
in question often look like this:

bb262:		; preds = %bb261, %bb248
	%iftmp.251.0 = phi i1 [ true, %bb261 ], [ false, %bb248 ]		; <i1> [#uses=4]
	%tmp270 = icmp eq %struct.rtx_def* %tmp.0.i, null		; <i1> [#uses=1]
	%bothcond = or i1 %iftmp.251.0, %tmp270		; <i1> [#uses=1]
	br i1 %bothcond, label %bb288, label %bb273

In this case, it is clear that it doesn't matter if tmp.0.i is null when coming from bb261.  When coming from bb248, it is all that matters.


Another random example:

check_asm_operands.exit:		; preds = %check_asm_operands.exit.thr_comm, %bb30.i, %bb12.i, %bb6.i413
	%tmp.0.i420 = phi i1 [ true, %bb6.i413 ], [ true, %bb12.i ], [ true, %bb30.i ], [ false, %check_asm_operands.exit.thr_comm ; <i1> [#uses=1]
	call void @llvm.stackrestore( i8* %savedstack ) nounwind 
	%tmp4389 = icmp eq i32 %added_sets_1.0, 0		; <i1> [#uses=1]
	%tmp4394 = icmp eq i32 %added_sets_2.0, 0		; <i1> [#uses=1]
	%bothcond80 = and i1 %tmp4389, %tmp4394		; <i1> [#uses=1]
	%bothcond81 = and i1 %bothcond80, %tmp.0.i420		; <i1> [#uses=1]
	br i1 %bothcond81, label %bb4398, label %bb4397

Here is the case from 252.eon:

bb290.i.i:		; preds = %bb23.i57.i.i, %bb8.i39.i.i, %bb100.i.i, %bb100.i.i, %bb85.i.i110
	%myEOF.1.i.i = phi i1 [ true, %bb100.i.i ], [ true, %bb100.i.i ], [ true, %bb85.i.i110 ], [ true, %bb8.i39.i.i ], [ false, %bb23.i57.i.i ]		; <i1> [#uses=2]
	%i.4.i.i = phi i32 [ %i.1.i.i, %bb85.i.i110 ], [ %i.0.i.i, %bb100.i.i ], [ %i.0.i.i, %bb100.i.i ], [ %i.3.i.i, %bb8.i39.i.i ], [ %i.3.i.i, %bb23.i57.i.i ]		; <i32> [#uses=3]
	%tmp292.i.i = load i8* %tmp16.i.i100, align 1		; <i8> [#uses=1]
	%tmp293.not.i.i = icmp ne i8 %tmp292.i.i, 0		; <i1> [#uses=1]
	%bothcond.i.i = and i1 %tmp293.not.i.i, %myEOF.1.i.i		; <i1> [#uses=1]
	br i1 %bothcond.i.i, label %bb202.i.i, label %bb301.i.i
  Factoring out 3 common predecessors.

On the path from any blocks other than bb23.i57.i.i, the load and compare 
are dead.

llvm-svn: 50096
2008-04-22 07:05:46 +00:00
Chris Lattner 3cc28ce1ed add a basic testcase.
llvm-svn: 50093
2008-04-22 06:35:14 +00:00