this LLVM function:

int %foo() {
        ret int cast (int** getelementptr (int** null, int 1) to int)
}

into:

foo:
        mov %EAX, 0
        lea %EAX, DWORD PTR [%EAX + 4]
        ret

now we compile it into:

foo:
        mov %EAX, 4
        ret

This sequence is frequently generated by the MSIL front-end, and soon the malloc lowering pass and
Java front-ends as well..

-Chris

llvm-svn: 14834

llvm-svn: 14833

llvm-svn: 14832

that is made unnecessary by it.

llvm-svn: 14831

* Simplify a lot of code because type's cannot be in function symbol tables
* Fix memory leaks in handling of redefined function prototypes
* Don't use SymbolTable directly for stuff that we can go through the Module
  for.
* Fix some minor bugs on obscure testcases like:
      test/Feature/globalredefinition.ll
* Do not create GlobalVariable objects for forward referenced Functions!
* When forward referencing a function in a constant expression, do not create
  a placeholder, add a bunch of references to it, then turn around and
  replaceAllUsesOfWith on it with a new global, deleting the placeholder.
  Instead, when we find the real definition of the global, just use the
  placeholder instead of creating a new object.

This substantially simplifies the asmwriter and should even speed it up on
cases heavy in constantexprs (like C++, Java, MSIL)...

llvm-svn: 14830

llvm-svn: 14829

  replaceAllUsesWith'ing any forward references, just use the forward
  reference if it exists.

This introduces GetForwardRefForGlobal, which will eventually completely
replace the horrible DeclareNewGlobalValue function.

llvm-svn: 14828

to substantially simplify the result.  In particular, we no longer create
GlobalVariables and then immediately destroy them when they are duplciate
definitions.

The real point of this patch though is that it gets us closer to the
DeclareNewGlobalValue calls...

llvm-svn: 14827

llvm-svn: 14826

llvm-svn: 14825

hold.  Because types are basically immutable anyway, they should not be
referenced as "const Type*" everywhere.  Just "Type*" should suffice!

llvm-svn: 14824

functions multiple times, expecting them to be merged.  This should be fixed
in the CFE, then here.

llvm-svn: 14823

llvm-svn: 14822

llvm-svn: 14821

* Add comments
* Add two new gep ctors for the very common case of creating a two operand
  GEP instruction.

llvm-svn: 14820

llvm-svn: 14819

* Clarify variable name (StoreInst SI instead of LI)

llvm-svn: 14818

This gives us only a single call site for setValueNameMergingDuplicates.
The next stage is the start merging them together.

llvm-svn: 14811

Since the stupid '%X = const int 4' thing is gone, we can now simplify
setValueNameMergingDuplicates a bit more.

llvm-svn: 14810

llvm-svn: 14809

llvm-svn: 14808

for a basic block, use it when the block is defined instead of deleting it
and creating a new one.  Also, only create at most ONE forward reference
for any block, instead of one for each forward reference.

llvm-svn: 14807

llvm-svn: 14806

llvm-svn: 14805

llvm-svn: 14801

llvm-svn: 14800

* Correctly load FP constants from the constant pool, should be refactored

llvm-svn: 14799

error messages because verification stops at the first error.

llvm-svn: 14794

error.  Just print the message like a good little tool.

llvm-svn: 14793

llvm-svn: 14792

forward reference blocks if they have been created (instead of creating a new
block, replaceAllUsesOfWith, then nuking the placeholder).   This is not yet
implemented.

llvm-svn: 14791

just to keep track of some per-object state!  Gaah!  Whoever wrote this stuff...
oh wait, that would be me.  Never mind.

llvm-svn: 14790

llvm-svn: 14789

the funciton symbol table to check for conflicts instead of having to
keep a shadow named LocalSymtab.  Totally eliminate LocalSymtab.  Verified
that this did not cause a regression on the testcase for PR107.

llvm-svn: 14788

  1. Split setValueName into two separate functions, one that is only used
     at function scope and doesn't have to deal with duplicates, and one
     that can be used either at global or function scope but that does deal
     with conflicts.  Conflicts were only in there because of the crappy old
     CFE and probably should be entirely eliminated.
  2. Insert BasicBlock's into the parent functions when they are created
     instead of when they are complete.  This effects name lookup (for the
     better), which will be exploited in the next patch.

llvm-svn: 14787

llvm-svn: 14786

code.

llvm-svn: 14785

at all.  Patch contributed by Vladimir Prus!

llvm-svn: 14784

"load (cast foo)".  This allows us to compile C++ code like this:

class Bclass {
  public: virtual int operator()() { return 666; }
};

class Dclass: public Bclass {
  public: virtual int operator()() { return 667; }
} ;

int main(int argc, char** argv) {
  Dclass x;
  return x();
}

Into this:

int %main(int %argc, sbyte** %argv) {
entry:
        call void %__main( )
        ret int 667
}

Instead of this:

int %main(int %argc, sbyte** %argv) {
entry:
        %x = alloca "struct.std::bad_typeid"            ; <"struct.std::bad_typeid"*> [#uses=3]
        call void %__main( )
        %tmp.1.i.i = getelementptr "struct.std::bad_typeid"* %x, uint 0, uint 0, uint 0         ; <int (...)***> [#uses=1]
        store int (...)** getelementptr ([3 x int (...)*]*  %vtable for Bclass, int 0, long 2), int (...)*** %tmp.1.i.i
        %tmp.3.i = getelementptr "struct.std::bad_typeid"* %x, int 0, uint 0, uint 0            ; <int (...)***> [#uses=1]
        store int (...)** getelementptr ([3 x int (...)*]*  %vtable for Dclass, int 0, long 2), int (...)*** %tmp.3.i
        %tmp.5 = load int ("struct.std::bad_typeid"*)** cast (int (...)** getelementptr ([3 x int (...)*]*  %vtable for Dclass, int 0, long 2) to int
("struct.std::bad_typeid"*)**)          ; <int ("struct.std::bad_typeid"*)*> [#uses=1]
        %tmp.6 = call int %tmp.5( "struct.std::bad_typeid"* %x )                ; <int> [#uses=1]
	ret int %tmp.6
        ret int 0
}

In order words, we now resolve the virtual function call.

llvm-svn: 14783

llvm-svn: 14782