Commit Graph

38 Commits

Author SHA1 Message Date
Dan Gohman 4a63fad976 Teach SimplifyCFG how to simplify indirectbr instructions.
- Eliminate redundant successors.
 - Convert an indirectbr with one successor into a direct branch.

Also, generalize SimplifyCFG to be able to be run on a function entry block.
It knows quite a few simplifications which are applicable to the entry
block, and it only needs a few checks to avoid trouble with the entry block.

llvm-svn: 111060
2010-08-14 00:29:42 +00:00
Owen Anderson a7aed18624 Reapply r110396, with fixes to appease the Linux buildbot gods.
llvm-svn: 110460
2010-08-06 18:33:48 +00:00
Owen Anderson bda59bd247 Revert r110396 to fix buildbots.
llvm-svn: 110410
2010-08-06 00:23:35 +00:00
Owen Anderson 755aceb5d0 Don't use PassInfo* as a type identifier for passes. Instead, use the address of the static
ID member as the sole unique type identifier.  Clean up APIs related to this change.

llvm-svn: 110396
2010-08-05 23:42:04 +00:00
Owen Anderson a57b97e7e7 Fix batch of converting RegisterPass<> to INTIALIZE_PASS().
llvm-svn: 109045
2010-07-21 22:09:45 +00:00
Benjamin Kramer b82de426de SimplifyCFG: don't turn volatile stores to null/undef into unreachable. Fixes PR7369.
llvm-svn: 105914
2010-06-13 14:35:54 +00:00
Chris Lattner 84d4618659 make simplifycfg insert an llvm.trap before the 'unreachable' it introduces
when it detects undefined behavior.  llvm.trap generally codegens into some
thing really small (e.g. a 2 byte ud2 instruction on x86) and debugging this
sort of thing is "nontrivial".  For example, we now compile:

void foo() { *(int*)0 = 42; }

into:

_foo:
	pushl	%ebp
	movl	%esp, %ebp
	ud2

Some may even claim that this is a security hole, though that seems dubious
to me.  This addresses rdar://7958343 - Optimizing away null dereference 
potentially allows arbitrary code execution

llvm-svn: 103356
2010-05-08 22:15:59 +00:00
Gabor Greif a2fbc0ae1b Finally land the InvokeInst operand reordering.
I have audited all getOperandNo calls now, fixing
hidden assumptions. CallSite related uglyness will
be eliminated successively.

Note this patch has a long and griveous history,
for all the back-and-forths have a look at
CallSite.h's log.

llvm-svn: 99399
2010-03-24 13:21:49 +00:00
Gabor Greif e1517a084f backing out r99170 because it still fails on clang-x86_64-darwin10-fnt
llvm-svn: 99171
2010-03-22 09:11:00 +00:00
Gabor Greif 7a743e15e3 Now that hopefully all direct accesses to InvokeInst operands are fixed
we can reapply the InvokeInst operand reordering patch. (see r98957).

llvm-svn: 99170
2010-03-22 08:28:00 +00:00
Gabor Greif 6c56ed847e back out r98957, it broke http://smooshlab.apple.com:8010/builders/clang-x86_64-darwin10-fnt/builds/703 in the nightly test suite
llvm-svn: 98958
2010-03-19 13:50:02 +00:00
Gabor Greif 8335f9c0bf Recommit r80858 again (which has been backed out in r80871).
This time I did a self-hosted bootstrap on Linux x86-64,
with no problems. Let's see how darwin 64-bit self-hosting
goes. At the first sign of failure I'll back this out.

Maybe the valgrind bots give me a hint of what may be wrong
(it at all).

llvm-svn: 98957
2010-03-19 11:55:53 +00:00
Devang Patel d3f41e8939 In "empty" bb, the return instruction may not be first instruction, if dbg value intrinsics are present in this bb. Use terminator to find return instructions.
llvm-svn: 98565
2010-03-15 19:05:46 +00:00
Bill Wendling 55e69d179b Skip over debug info when trying to merge two return BBs.
llvm-svn: 98491
2010-03-14 10:40:55 +00:00
Jakob Stoklund Olesen 916f48a054 Teach SimplifyCFG about magic pointer constants.
Weird code sometimes uses pointer constants other than null. This patch
teaches SimplifyCFG to build switch instructions in those cases.

Code like this:

void f(const char *x) {
  if (!x)
    puts("null");
  else if ((uintptr_t)x == 1)
    puts("one");
  else if (x == (char*)2 || x == (char*)3)
    puts("two");
  else if ((intptr_t)x == 4)
    puts("four");
  else
    puts(x);
}

Now becomes a switch:

define void @f(i8* %x) nounwind ssp {
entry:
  %magicptr23 = ptrtoint i8* %x to i64            ; <i64> [#uses=1]
  switch i64 %magicptr23, label %if.else16 [
    i64 0, label %if.then
    i64 1, label %if.then2
    i64 2, label %if.then9
    i64 3, label %if.then9
    i64 4, label %if.then14
  ]

Note that LLVM's own DenseMap uses magic pointers.

llvm-svn: 95439
2010-02-05 22:03:18 +00:00
Dan Gohman 28943873e6 Use do+while instead of while for loops which obviously have a
non-zero trip count. Use SmallVector's pop_back_val().

llvm-svn: 92734
2010-01-05 16:27:25 +00:00
Chris Lattner f21a220bcd Implement PR5795 by merging duplicated return blocks. This could go further
by merging all returns in a function into a single one, but simplifycfg 
currently likes to duplicate the return (an unfortunate choice!)

llvm-svn: 91890
2009-12-22 06:07:30 +00:00
Nick Lewycky 621fe5614e Remove LLVMContext and its include.
llvm-svn: 89644
2009-11-23 03:34:29 +00:00
Chris Lattner 37536b90e1 remove a bunch of locking from LLVMContextImpl. Since only one thread
can be banging on a context at a time, this isn't needed.  Owen, please
review.

llvm-svn: 85728
2009-11-01 18:42:03 +00:00
Gabor Greif 2d60e1ec0c back out my recent commit (r80858), it seems to break self-hosting buildbot's stage 2 configure
llvm-svn: 80871
2009-09-03 02:02:59 +00:00
Gabor Greif 14dfba6d66 re-commit r66920 (which has been backed out in r66953) I may have more luck this time. I'll back out if needed...
llvm-svn: 80858
2009-09-03 00:18:58 +00:00
Chris Lattner 2dd09dbdf7 eliminate VISIBILITY_HIDDEN from Transforms/Scalar. PR4861
llvm-svn: 80766
2009-09-02 06:11:42 +00:00
Chris Lattner a3e620caba add getPointerAddressSpace() to GEP instruction, use the method
in a few scalar xforms to simplify things.

llvm-svn: 80506
2009-08-30 20:06:40 +00:00
Owen Anderson 55f1c09e31 Push LLVMContexts through the IntegerType APIs.
llvm-svn: 78948
2009-08-13 21:58:54 +00:00
Owen Anderson b292b8ce70 Move more code back to 2.5 APIs.
llvm-svn: 77635
2009-07-30 23:03:37 +00:00
Owen Anderson 47db941fd3 Get rid of the Pass+Context magic.
llvm-svn: 76702
2009-07-22 00:24:57 +00:00
Dale Johannesen 3be62697df Revert 75571; I'm convinced this isn't the right thing to do.
llvm-svn: 75642
2009-07-14 17:48:25 +00:00
Dale Johannesen 85ae7480d9 Don't delete asm's just because their inputs are undefined;
xor R, R is a common and valid idiom for zeroing a register, for example.

llvm-svn: 75571
2009-07-14 00:45:38 +00:00
Owen Anderson 38264b1554 "LLVMContext* " --> "LLVMContext *"
llvm-svn: 74878
2009-07-06 23:00:19 +00:00
Owen Anderson 340288c621 Even more passes being LLVMContext'd.
llvm-svn: 74781
2009-07-03 19:42:02 +00:00
Chris Lattner 3dd5c5d28a second half of fix for PR4366: don't zap store to null of
non-default addrspaces.

llvm-svn: 73253
2009-06-12 21:01:07 +00:00
Bill Wendling 4bb96e9a50 Revert r66920. It was causing failures in the self-hosting buildbot (in release
mode).

Running /Volumes/Sandbox/Buildbot/llvm/full-llvm/build/llvmCore/test/BugPoint/dg.exp ...
FAIL: /Volumes/Sandbox/Buildbot/llvm/full-llvm/build/llvmCore/test/BugPoint/crash-narrowfunctiontest.ll
Failed with signal(SIGBUS) at line 1
while running: bugpoint /Volumes/Sandbox/Buildbot/llvm/full-llvm/build/llvmCore/test/BugPoint/crash-narrowfunctiontest.ll -bugpoint-crashcalls -silence-passes > /dev/null
0   bugpoint          0x0035dd25 llvm::sys::SetInterruptFunction(void (*)()) + 85
1   bugpoint          0x0035e382 llvm::sys::RemoveFileOnSignal(llvm::sys::Path const&, std::string*) + 706
2   libSystem.B.dylib 0x92f112bb _sigtramp + 43
3   libSystem.B.dylib 0xffffffff _sigtramp + 1829694831
4   bugpoint          0x00021d1c main + 92
5   bugpoint          0x00002106 start + 54
6   bugpoint          0x00000004 start + 18446744073709543220
Stack dump:
0.    Program arguments: bugpoint /Volumes/Sandbox/Buildbot/llvm/full-llvm/build/llvmCore/test/BugPoint/crash-narrowfunctiontest.ll -bugpoint-crashcalls -silence-passes 

FAIL: /Volumes/Sandbox/Buildbot/llvm/full-llvm/build/llvmCore/test/BugPoint/misopt-basictest.ll
Failed with signal(SIGBUS) at line 1
while running: bugpoint /Volumes/Sandbox/Buildbot/llvm/full-llvm/build/llvmCore/test/BugPoint/misopt-basictest.ll -dce -bugpoint-deletecalls -simplifycfg -silence-passes
0   bugpoint          0x0035dd25 llvm::sys::SetInterruptFunction(void (*)()) + 85
1   bugpoint          0x0035e382 llvm::sys::RemoveFileOnSignal(llvm::sys::Path const&, std::string*) + 706
2   libSystem.B.dylib 0x92f112bb _sigtramp + 43
3   libSystem.B.dylib 0xffffffff _sigtramp + 1829694831
4   bugpoint          0x00021d1c main + 92
5   bugpoint          0x00002106 start + 54
6   bugpoint          0x00000006 start + 18446744073709543222
Stack dump:
0.    Program arguments: bugpoint /Volumes/Sandbox/Buildbot/llvm/full-llvm/build/llvmCore/test/BugPoint/misopt-basictest.ll -dce -bugpoint-deletecalls -simplifycfg -silence-passes 

FAIL: /Volumes/Sandbox/Buildbot/llvm/full-llvm/build/llvmCore/test/BugPoint/remove_arguments_test.ll
Failed with signal(SIGBUS) at line 1
while running: bugpoint /Volumes/Sandbox/Buildbot/llvm/full-llvm/build/llvmCore/test/BugPoint/remove_arguments_test.ll  -bugpoint-crashcalls -silence-passes
0   bugpoint          0x0035dd25 llvm::sys::SetInterruptFunction(void (*)()) + 85
1   bugpoint          0x0035e382 llvm::sys::RemoveFileOnSignal(llvm::sys::Path const&, std::string*) + 706
2   libSystem.B.dylib 0x92f112bb _sigtramp + 43
3   libSystem.B.dylib 0xffffffff _sigtramp + 1829694831
4   bugpoint          0x00021d1c main + 92
5   bugpoint          0x00002106 start + 54
Stack dump:
0.    Program arguments: bugpoint /Volumes/Sandbox/Buildbot/llvm/full-llvm/build/llvmCore/test/BugPoint/remove_arguments_test.ll -bugpoint-crashcalls -silence-passes 

--- Reverse-merging (from foreign repository) r66920 into '.':
U    include/llvm/Support/CallSite.h
U    include/llvm/Instructions.h
U    lib/Analysis/IPA/GlobalsModRef.cpp
U    lib/Analysis/IPA/Andersens.cpp
U    lib/Bitcode/Writer/BitcodeWriter.cpp
U    lib/VMCore/Instructions.cpp
U    lib/VMCore/Verifier.cpp
U    lib/VMCore/AsmWriter.cpp
U    lib/Transforms/Utils/LowerInvoke.cpp
U    lib/Transforms/Scalar/SimplifyCFGPass.cpp
U    lib/Transforms/IPO/PruneEH.cpp
U    lib/Transforms/IPO/DeadArgumentElimination.cpp

llvm-svn: 66953
2009-03-13 21:15:59 +00:00
Gabor Greif 258232fb80 Second installment of "BasicBlock operands to the back"
changes.

For InvokeInst now all arguments begin at op_begin().
The Callee, Cont and Fail are now faster to get by
access relative to op_end().

This patch introduces some temporary uglyness in CallSite.
Next I'll bring CallInst up to a similar scheme and then
the uglyness will magically vanish.

This patch also exposes all the reliance of the libraries
on InvokeInst's operand ordering. I am thinking of taking
care of that too.

llvm-svn: 66920
2009-03-13 18:27:29 +00:00
Devang Patel 4c758ea3e0 Large mechanical patch.
s/ParamAttr/Attribute/g
s/PAList/AttrList/g
s/FnAttributeWithIndex/AttributeWithIndex/g
s/FnAttr/Attribute/g

This sets the stage 
- to implement function notes as function attributes and 
- to distinguish between function attributes and return value attributes.

This requires corresponding changes in llvm-gcc and clang.

llvm-svn: 56622
2008-09-25 21:00:45 +00:00
Devang Patel ba3fa6c6e1 s/ParameterAttributes/Attributes/g
llvm-svn: 56513
2008-09-23 23:03:40 +00:00
Devang Patel 3d56051f70 s/RemoveUnreachableBlocks/RemoveUnreachableBlocksFromFn/g
llvm-svn: 55965
2008-09-08 22:14:17 +00:00
Dan Gohman a79db30d28 Tidy up several unbeseeming casts from pointer to intptr_t.
llvm-svn: 55779
2008-09-04 17:05:41 +00:00
Chris Lattner e15051d64b rename SimplifyCFG.cpp -> SimplifyCFGPass.cpp
llvm-svn: 51130
2008-05-14 20:38:44 +00:00