Commit Graph

1229 Commits

Author SHA1 Message Date
Chris Lattner
4279f3c984 Fix PR255: [tailduplication] Single basic block loops are very rare
Note that this is a band-aid put over a band-aid.  This just undisables
tail duplication in on very specific case that it seems to work in.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11989 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-29 06:41:20 +00:00
Chris Lattner
542f149f00 Implement switch->br and br->switch folding by ripping out the switch->switch
and br->br code and generalizing it.  This allows us to compile code like this:

int test(Instruction *I) {
  if (isa<CastInst>(I))
    return foo(7);
  else if (isa<BranchInst>(I))
    return foo(123);
  else if (isa<UnwindInst>(I))
    return foo(1241);
  else if (isa<SetCondInst>(I))
    return foo(1);
  else if (isa<VAArgInst>(I))
    return foo(42);
  return foo(-1);
}

into:

int %_Z4testPN4llvm11InstructionE("struct.llvm::Instruction"* %I) {
entry:
        %tmp.1.i.i.i.i.i.i.i = getelementptr "struct.llvm::Instruction"* %I, long 0, ubyte 4            ; <uint*> [#uses=1]
        %tmp.2.i.i.i.i.i.i.i = load uint* %tmp.1.i.i.i.i.i.i.i          ; <uint> [#uses=2]
        %tmp.2.i.i.i.i.i.i = seteq uint %tmp.2.i.i.i.i.i.i.i, 27                ; <bool> [#uses=0]
        switch uint %tmp.2.i.i.i.i.i.i.i, label %endif.0 [
                 uint 27, label %then.0
                 uint 2, label %then.1
                 uint 5, label %then.2
                 uint 14, label %then.3
                 uint 15, label %then.3
                 uint 16, label %then.3
                 uint 17, label %then.3
                 uint 18, label %then.3
                 uint 19, label %then.3
                 uint 32, label %then.4
        ]
...

As well as handling the cases in 176.gcc and many other programs more effectively.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11964 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-28 21:28:10 +00:00
Chris Lattner
b99df4f8c2 if there is already a prototype for malloc/free, use it, even if it's incorrect.
Do not just inject a new prototype.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11951 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-28 18:51:45 +00:00
Chris Lattner
7bcc0e7fff Rename AddUsesToWorkList -> AddUsersToWorkList, as that is what it does.
Create a new AddUsesToWorkList method
optimize memmove/set/cpy of zero bytes to a noop.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11941 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-28 05:22:00 +00:00
Chris Lattner
6160e85201 Turn 'free null' into nothing
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11940 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-28 04:57:37 +00:00
Misha Brukman
9e4a642c03 Right, it's really Extractor, not Extraction.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11939 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-28 03:37:58 +00:00
Misha Brukman
9401deb320 A pass that uses the generic CodeExtractor to rip out *every* loop in every
function, as long as the loop isn't the only one in that function. This should
help debugging passes easier with BugPoint.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11936 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-28 03:33:01 +00:00
Misha Brukman
e6336031b8 A generic code extractor: given a list of BasicBlocks, it will rip them out into
a new function, taking care of inputs and outputs.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11935 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-28 03:26:20 +00:00
Chris Lattner
7d90a2738e setcond instructions don't have aliasing implications.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11919 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-27 18:09:25 +00:00
Chris Lattner
a0ebcebc06 Implement test/Regression/Transforms/InstCombine/canonicalize_branch.ll
This is a really minor thing, but might help out the 'switch statement induction'
code in simplifycfg.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11900 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-27 06:27:46 +00:00
Chris Lattner
4f77caaa3d Since LLVM uses structure type equivalence, it isn't useful to keep around
multiple type names for the same structural type.  Make DTE eliminate all
but one of the type names


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11879 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-26 20:02:23 +00:00
Chris Lattner
f2dbf50efa turn things like:
if (X == 0 || X == 2)

...where the comparisons and branches are in different blocks... into a switch
instruction.  This comes up a lot in various programs, and works well with
the switch/switch merging code I checked earlier.  For example, this testcase:

int switchtest(int C) {
  return C == 0 ? f(123) :
         C == 1 ? f(3123) :
         C == 4 ? f(312) :
         C == 5 ? f(1234): f(444);
}

is converted into this:
        switch int %C, label %cond_false.3 [
                 int 0, label %cond_true.0
                 int 1, label %cond_true.1
                 int 4, label %cond_true.2
                 int 5, label %cond_true.3
        ]

instead of a whole bunch of conditional branches.

Admittedly the code is ugly, and incomplete.  To be complete, we need to add
br -> switch merging and switch -> br merging.  For example, this testcase:

struct foo { int Q, R, Z; };
#define A (X->Q+X->R * 123)
int test(struct foo *X) {
  return A  == 123 ? X1() :
        A == 12321 ? X2():
        (A == 111 || A == 222) ? X3() :
        A == 875 ? X4() : X5();
}

Gets compiled to this:
        switch int %tmp.7, label %cond_false.2 [
                 int 123, label %cond_true.0
                 int 12321, label %cond_true.1
                 int 111, label %cond_true.2
                 int 222, label %cond_true.2
        ]
...
cond_false.2:           ; preds = %entry
        %tmp.52 = seteq int %tmp.7, 875         ; <bool> [#uses=1]
        br bool %tmp.52, label %cond_true.3, label %cond_false.3

where the branch could be folded into the switch.

This kind of thing occurs *ALL OF THE TIME*, especially in programs like
176.gcc, which is a horrible mess of code.  It contains stuff like *shudder*:

#define SWITCH_TAKES_ARG(CHAR) \
  (   (CHAR) == 'D' \
   || (CHAR) == 'U' \
   || (CHAR) == 'o' \
   || (CHAR) == 'e' \
   || (CHAR) == 'u' \
   || (CHAR) == 'I' \
   || (CHAR) == 'm' \
   || (CHAR) == 'L' \
   || (CHAR) == 'A' \
   || (CHAR) == 'h' \
   || (CHAR) == 'z')

and

#define CONST_OK_FOR_LETTER_P(VALUE, C)                 \
  ((C) == 'I' ? SMALL_INTVAL (VALUE)                    \
   : (C) == 'J' ? SMALL_INTVAL (-(VALUE))               \
   : (C) == 'K' ? (unsigned)(VALUE) < 32                \
   : (C) == 'L' ? ((VALUE) & 0xffff) == 0               \
   : (C) == 'M' ? integer_ok_for_set (VALUE)            \
   : (C) == 'N' ? (VALUE) < 0                           \
   : (C) == 'O' ? (VALUE) == 0                          \
   : (C) == 'P' ? (VALUE) >= 0                          \
   : 0)

and

#define LEGITIMIZE_ADDRESS(X,OLDX,MODE,WIN)                     \
{                                                               \
  if (GET_CODE (X) == PLUS && CONSTANT_ADDRESS_P (XEXP (X, 1))) \
    (X) = gen_rtx (PLUS, SImode, XEXP (X, 0),                   \
                   copy_to_mode_reg (SImode, XEXP (X, 1)));     \
  if (GET_CODE (X) == PLUS && CONSTANT_ADDRESS_P (XEXP (X, 0))) \
    (X) = gen_rtx (PLUS, SImode, XEXP (X, 1),                   \
                   copy_to_mode_reg (SImode, XEXP (X, 0)));     \
  if (GET_CODE (X) == PLUS && GET_CODE (XEXP (X, 0)) == MULT)   \
    (X) = gen_rtx (PLUS, SImode, XEXP (X, 1),                   \
                   force_operand (XEXP (X, 0), 0));             \
  if (GET_CODE (X) == PLUS && GET_CODE (XEXP (X, 1)) == MULT)   \
    (X) = gen_rtx (PLUS, SImode, XEXP (X, 0),                   \
                   force_operand (XEXP (X, 1), 0));             \
  if (GET_CODE (X) == PLUS && GET_CODE (XEXP (X, 0)) == PLUS)   \
    (X) = gen_rtx (PLUS, Pmode, force_operand (XEXP (X, 0), NULL_RTX),\
                   XEXP (X, 1));                                \
  if (GET_CODE (X) == PLUS && GET_CODE (XEXP (X, 1)) == PLUS)   \
    (X) = gen_rtx (PLUS, Pmode, XEXP (X, 0),                    \
                   force_operand (XEXP (X, 1), NULL_RTX));      \
  if (GET_CODE (X) == SYMBOL_REF || GET_CODE (X) == CONST       \
           || GET_CODE (X) == LABEL_REF)                        \
    (X) = legitimize_address (flag_pic, X, 0, 0);               \
  if (memory_address_p (MODE, X))                               \
    goto WIN; }

and others.  These macros get used multiple times of course.  These are such
lovely candidates for macros, aren't they?  :)

This code also nicely handles LLVM constructs that look like this:

  if (isa<CastInst>(I))
   ...
  else if (isa<BranchInst>(I))
   ...
  else if (isa<SetCondInst>(I))
   ...
  else if (isa<UnwindInst>(I))
   ...
  else if (isa<VAArgInst>(I))
   ...

where the isa can obviously be a dyn_cast as well.  Switch instructions are a
good thing.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11870 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-26 07:13:46 +00:00
Chris Lattner
079236d1c9 My faith in programmers has been found to be totally misplaced. One would
assume that if they don't intend to write to a global variable, that they
would mark it as constant.  However, there are people that don't understand
that the compiler can do nice things for them if they give it the information
it needs.

This pass looks for blatently obvious globals that are only ever read from.
Though it uses a trivially simple "alias analysis" of sorts, it is still able
to do amazing things to important benchmarks.  253.perlbmk, for example,
contains several ***GIANT*** function pointer tables that are not marked
constant and should be.  Marking them constant allows the optimizer to turn
a whole bunch of indirect calls into direct calls.  Note that only a link-time
optimizer can do this transformation, but perlbmk does have several strings
and other minor globals that can be marked constant by this pass when run
from GCCAS.

176.gcc has a ton of strings and large tables that are marked constant, both
at compile time (38 of them) and at link time (48 more).  Other benchmarks
give similar results, though it seems like big ones have disproportionally
more than small ones.

This pass is extremely quick and does good things.  I'm going to enable it
in gccas & gccld.  Not bad for 50 SLOC.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11836 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-25 21:34:36 +00:00
Chris Lattner
940ff563f7 Fix incorrect debug code
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11821 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-25 15:15:04 +00:00
Chris Lattner
d38f208cd9 Fix a faulty optimization on FP values
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11801 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-24 18:10:14 +00:00
Chris Lattner
8e509dd5e8 If a block is made dead, make sure to promptly remove it.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11799 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-24 16:09:21 +00:00
Chris Lattner
d52c261cf8 Implement SimplifyCFG/switch_switch_fold.ll
This case occurs many times in various benchmarks, especially when combined
with the previous patch.  This allows it to get stuff like:
  if (X == 4 || X == 3)
    if (X == 5 || X == 8)

and

switch (X) {
case 4: case 5: case 6:
  if (X == 4 || X == 5)


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11797 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-24 07:23:58 +00:00
Chris Lattner
e14ea0804a Rearrange code a bit
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11793 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-24 05:54:22 +00:00
Chris Lattner
0d56008f53 Implement: test/Regression/Transforms/SimplifyCFG/switch_create.ll
This turns code like this:
  if (X == 4 | X == 7)
and
  if (X != 4 & X != 7)
into switch instructions.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11792 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-24 05:38:11 +00:00
Chris Lattner
d8864ce766 Generate much more efficient code in programs like pifft
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11775 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-23 21:46:58 +00:00
Chris Lattner
077a373791 Fix a small typeo in my checkin last night that broke vortex and other programs :(
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11774 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-23 21:46:42 +00:00
Chris Lattner
8adac75298 Fix InstCombine/2004-02-23-ShiftShiftOverflow.ll
Also, turn 'shr int %X, 1234' into 'shr int %X, 31'


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11768 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-23 20:30:06 +00:00
Chris Lattner
c5943fb186 Implement cast.ll::test14/15
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11742 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-23 07:16:20 +00:00
Chris Lattner
4cb170cc6e Refactor some code. In the mul - setcc folding case, we really care about
whether this is the sign bit or not, so check unsigned comparisons as well.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11740 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-23 06:38:22 +00:00
Chris Lattner
fed58fd72e Implement mul.ll:test11
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11737 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-23 06:00:11 +00:00
Chris Lattner
45aaafef49 Implement "strength reduction" of X <= C and X >= C
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11735 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-23 05:47:48 +00:00
Chris Lattner
fb54b2b744 Implement InstCombine/mul.ll:test10, which is a case that occurs when dealing
with "predication"


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11734 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-23 05:39:21 +00:00
Chris Lattner
c6bd195336 Implement Transforms/InstCombine/cast.ll:test13, a case which occurs in a
hot 164.gzip loop.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11702 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-22 05:25:17 +00:00
Chris Lattner
57cb9883aa Fix PR245: Linking weak and strong global variables is dependent on link order
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11565 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-17 21:56:04 +00:00
Chris Lattner
19831ec853 Implement test/Regression/Transforms/SimplifyCFG/UncondBranchToReturn.ll,
see the testcase for the reasoning.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11496 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-16 06:35:48 +00:00
Chris Lattner
7059f2e76b Fold PHI nodes of constants which are only used by a single cast. This implements
phi.ll:test4


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11494 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-16 05:07:08 +00:00
Chris Lattner
26ca7e145e Teach LLVM to unravel the "swap idiom". This implements:
Regression/Transforms/InstCombine/xor.ll:test20


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11492 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-16 03:54:20 +00:00
Chris Lattner
c317d39887 Implement Transforms/InstCombine/xor.ll:test19
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11490 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-16 01:20:27 +00:00
Chris Lattner
860a16143c Instead of producing calls to setjmp/longjmp, produce uses of the
llvm.setjmp/llvm.longjmp intrinsics.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11482 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-15 22:24:27 +00:00
Chris Lattner
de512b5b2e Adjustments to support the new ConstantAggregateZero class
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11474 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-15 05:55:15 +00:00
Chris Lattner
04d1fb6df9 Remove dependence on return type of ConstantStruct::get
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11466 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-15 04:07:32 +00:00
Chris Lattner
371064481a Remove dependence on the return type of ConstantArray::get
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11463 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-15 04:05:58 +00:00
Chris Lattner
494b6920b0 Fix compilation of 126.gcc: intrinsic functions cannot throw, so they are not
allowed in invoke instructions.  Thus, if we are inlining a call to an intrinsic
function into an invoke site, we don't need to turn the call into an invoke!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11384 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-13 16:47:35 +00:00
Chris Lattner
0db085baec Intrinsic functions cannot throw
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11383 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-13 16:46:46 +00:00
Chris Lattner
cefc18e7d9 Expose a pass ID that can be 'required'
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11376 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-13 16:16:16 +00:00
Chris Lattner
5f55aaf0f0 Remove obsolete comment. Unreachable blocks will automatically be left at the
end of the function.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11313 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-11 05:20:50 +00:00
Chris Lattner
206805e172 Add an _embarassingly simple_ implementation of basic block layout. This is
more of a testcase for profiling information than anything that should reasonably
be used, but it's a starting point.  When I have more time I will whip this into
better shape.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11311 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-11 04:53:20 +00:00
Chris Lattner
723c66d4c0 Implement SimplifyCFG/PhiEliminate.ll
Having a proper 'select' instruction would allow the elimination of a lot
of the special case cruft in this patch, but we don't have one yet.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11307 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-11 03:36:04 +00:00
Chris Lattner
2355f948c5 The hasConstantReferences predicate always returns false.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11301 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-11 01:17:07 +00:00
Chris Lattner
81d1a2207d initialization calls now return argc. If the program uses the argc value
passed into main, make sure they use the return value of the init call
instead of the one passed in.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11262 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-10 17:41:01 +00:00
Chris Lattner
f1d0d3519f Only add the global variable with the abort message if an unwind actually
occurs in the program.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11249 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-09 22:48:47 +00:00
Chris Lattner
68b86f4f41 Don't depend on auto data conversion
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11229 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-09 05:16:30 +00:00
Chris Lattner
d21cd809b6 Adjust to the changed StructType interface. In particular, getElementTypes() is gone.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11228 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-09 04:37:31 +00:00
Chris Lattner
d5d8996720 Start using the new and improve interface to FunctionType arguments
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11224 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-09 04:14:01 +00:00
Chris Lattner
99d6b8ec95 The ConstantExpr::getCast call can cause a CPR to be generated. If so,
strip it off.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11213 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-09 00:20:55 +00:00