Constant propagation should remove the dead instructions

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12917 91177308-0d34-0410-b5e6-96231b3b80d8

New testcase

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12916 91177308-0d34-0410-b5e6-96231b3b80d8

Regenerated using autoconf-2.57.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12915 91177308-0d34-0410-b5e6-96231b3b80d8

Rewrite POV-Ray check as per PR301

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12914 91177308-0d34-0410-b5e6-96231b3b80d8

Increase buffer size again. *sigh*

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12912 91177308-0d34-0410-b5e6-96231b3b80d8

Don't index spiff.  It should not count as lines of LLVM code

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12911 91177308-0d34-0410-b5e6-96231b3b80d8

Fixed sized limits are bad... duh.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12908 91177308-0d34-0410-b5e6-96231b3b80d8

Really spiff, don't chatter :)

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12907 91177308-0d34-0410-b5e6-96231b3b80d8

I don't think we have to have 4 extra allocated (but unused) bytes on the stack.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12905 91177308-0d34-0410-b5e6-96231b3b80d8

I started working on casts, but I don't have anything compilable yet.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12903 91177308-0d34-0410-b5e6-96231b3b80d8

Don't underline diffs

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12902 91177308-0d34-0410-b5e6-96231b3b80d8

Emit the immediate form of in/out when possible.
Fix several bugs in the intrinsics:
  1. Make sure to copy the input registers before the instructions that use them
  2. Make sure to copy the value returned by 'in' out of EAX into the register
     it is supposed to be in.

This fixes assertions when using in/out and linear scan.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12896 91177308-0d34-0410-b5e6-96231b3b80d8

Add immediate forms of in/out.  Use let to shorten lines

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12895 91177308-0d34-0410-b5e6-96231b3b80d8

Add support for new instruction type

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12894 91177308-0d34-0410-b5e6-96231b3b80d8

Add support for the printImplicitDefsBefore flag

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12893 91177308-0d34-0410-b5e6-96231b3b80d8

Make the testcase more challenging

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12892 91177308-0d34-0410-b5e6-96231b3b80d8

Reenable library now that the loopsimplify bug is fixed

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12891 91177308-0d34-0410-b5e6-96231b3b80d8

Fix LoopSimplify/2004-04-13-LoopSimplifyUpdateDomFrontier.ll

LoopSimplify was not updating dominator frontiers correctly in some cases.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12890 91177308-0d34-0410-b5e6-96231b3b80d8

New testcase where loop simplify is not updating domfrontiers correctly

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12889 91177308-0d34-0410-b5e6-96231b3b80d8

Refactor code a bit to make it simpler and eliminate the goto

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12888 91177308-0d34-0410-b5e6-96231b3b80d8

Add notes about some of the code quality improvements that have gone in

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12887 91177308-0d34-0410-b5e6-96231b3b80d8

Temporary hack to get the nightly tester running

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12886 91177308-0d34-0410-b5e6-96231b3b80d8

Added Spiff.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12885 91177308-0d34-0410-b5e6-96231b3b80d8

This patch addresses PR35: Loop simplify should reconstruct nested loops.
This is fairly straight-forward, but was a real nightmare to get just
perfect.  aarg.  :)

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12884 91177308-0d34-0410-b5e6-96231b3b80d8

Clean up the Spiff code so that it emits fewer warnings.  This
consists mostly of changing sloppy K&R C code to slightly more
disciplined K&R C code, and doing the usual things to shut gcc up.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12877 91177308-0d34-0410-b5e6-96231b3b80d8

Build Spiff directory

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12876 91177308-0d34-0410-b5e6-96231b3b80d8

Add the Spiff fp-aware diff utility from Bellcore

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12875 91177308-0d34-0410-b5e6-96231b3b80d8

We don't need to insert TargetData into the PassManager here.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12874 91177308-0d34-0410-b5e6-96231b3b80d8

new testcase

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12873 91177308-0d34-0410-b5e6-96231b3b80d8

Fix bug introduced in previous commit.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12872 91177308-0d34-0410-b5e6-96231b3b80d8

Add some methods that are useful for updating loop information.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12871 91177308-0d34-0410-b5e6-96231b3b80d8

Update testcase to illustrate the coalescing problem. The previous one did not work because of a fix in the x86 instruction selector.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12870 91177308-0d34-0410-b5e6-96231b3b80d8

Correctly compute spill weights

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12869 91177308-0d34-0410-b5e6-96231b3b80d8

Added testcase for the llvm.readport and llvm.writeport intrinsics.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12868 91177308-0d34-0410-b5e6-96231b3b80d8

Corrected the descriptions of the llvm.writeport and llvm.writeio
intrinsics.

Modified llvm.readio and llvm.writeio to use pointers to memory instead
of integers.  This should take care of problems such as different pointer
sizes, casting integers to pointers, weird architectural pointer types, etc.

Re-worded the description of llvm.readio and llvm.writeio so that it should
be more clear as to why they should be used over regular loads/stores for
I/O.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12867 91177308-0d34-0410-b5e6-96231b3b80d8

Print def lists a bit more compactly

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12866 91177308-0d34-0410-b5e6-96231b3b80d8

Add same value coalescing testcase

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12865 91177308-0d34-0410-b5e6-96231b3b80d8

Added initial design for the llvm.readio and llvm.writeio intrinsics.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12864 91177308-0d34-0410-b5e6-96231b3b80d8

Add a couple more IPO's

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12863 91177308-0d34-0410-b5e6-96231b3b80d8

finegrainify namespacification

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12862 91177308-0d34-0410-b5e6-96231b3b80d8

Actually update the call graph as the inliner changes it.  This allows us to
execute other CallGraphSCCPasses after the inliner without crashing.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12861 91177308-0d34-0410-b5e6-96231b3b80d8

Change the call graph class to have TWO external nodes, making call graph
SCC passes much more useful.  In particular, this should fix the incredibly
stupid missed inlining opportunities that the inliner suffered from.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12860 91177308-0d34-0410-b5e6-96231b3b80d8

Hrm, operator new and new[] do not belong here.  We should not CSE them!  :)

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12859 91177308-0d34-0410-b5e6-96231b3b80d8

Add support for removing invoke instructions

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12858 91177308-0d34-0410-b5e6-96231b3b80d8

Stop printing Function*

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12857 91177308-0d34-0410-b5e6-96231b3b80d8

Simplify code a bit, and be sure to mark the external node as potentially throwing

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12856 91177308-0d34-0410-b5e6-96231b3b80d8

Fix issues that the local allocator has dealing with instructions that implicitly use ST(0)

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12855 91177308-0d34-0410-b5e6-96231b3b80d8

No really, fix printing for LLC.  I gotta get a way for CVS to whine at me if
I have unsaved emacs buffers, geeze...

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12854 91177308-0d34-0410-b5e6-96231b3b80d8

Correct printing for LLC and the encoding for the JIT

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12853 91177308-0d34-0410-b5e6-96231b3b80d8

Use the fucomi[p] instructions to perform floating point comparisons instead
of the fucom[p][p] instructions.  This allows us to code generate this function

bool %test(double %X, double %Y) {
        %C = setlt double %Y, %X
        ret bool %C
}

... into:

test:
        fld QWORD PTR [%ESP + 4]
        fld QWORD PTR [%ESP + 12]
        fucomip %ST(1)
        fstp %ST(0)
        setb %AL
        movsx %EAX, %AL
        ret

where before we generated:

test:
        fld QWORD PTR [%ESP + 4]
        fld QWORD PTR [%ESP + 12]
        fucompp
**      fnstsw
**      sahf
        setb %AL
        movsx %EAX, %AL
        ret

The two marked instructions (which are the ones eliminated) are very bad,
because they serialize execution of the processor.  These instructions are
available on the PPRO and later, but since we already use cmov's we aren't
losing any portability.

I retained the old code for the day when we decide we want to support back
to the 386.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12852 91177308-0d34-0410-b5e6-96231b3b80d8

Add support for the FUCOMIr instruction

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12851 91177308-0d34-0410-b5e6-96231b3b80d8

Add two new instructions

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12850 91177308-0d34-0410-b5e6-96231b3b80d8

Fix a bug in my load/cast folding patch.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12849 91177308-0d34-0410-b5e6-96231b3b80d8

Adjust some comments, fix a bug in my previous patch

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12848 91177308-0d34-0410-b5e6-96231b3b80d8

Disambiguate symbols after loop extraction so that we can diagnose a code
generator bug if multiple loops are extracted from a function.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12847 91177308-0d34-0410-b5e6-96231b3b80d8

On X86, casting an integer to floating point requires going through memory.
If the source of the cast is a load, we can just use the source memory location,
without having to create a temporary stack slot entry.

Before we code generated this:

double %int(int* %P) {
        %V = load int* %P
        %V2 = cast int %V to double
        ret double %V2
}

into:

int:
        sub %ESP, 4
        mov %EAX, DWORD PTR [%ESP + 8]
        mov %EAX, DWORD PTR [%EAX]
        mov DWORD PTR [%ESP], %EAX
        fild DWORD PTR [%ESP]
        add %ESP, 4
        ret

Now we produce this:

int:
        mov %EAX, DWORD PTR [%ESP + 4]
        fild DWORD PTR [%EAX]
        ret

... which is nicer.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12846 91177308-0d34-0410-b5e6-96231b3b80d8

New testcase

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12845 91177308-0d34-0410-b5e6-96231b3b80d8

Implement folding of loads into floating point operations.  This implements:
test/Regression/CodeGen/X86/fp_load_fold.llx

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12844 91177308-0d34-0410-b5e6-96231b3b80d8

New testcase

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12843 91177308-0d34-0410-b5e6-96231b3b80d8

Unify all of the code for floating point +,-,*,/ into one function

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12842 91177308-0d34-0410-b5e6-96231b3b80d8

This implements folding of constant operands into floating point operations
for mul and div.

Instead of generating this:

test_divr:
        fld QWORD PTR [%ESP + 4]
        fld QWORD PTR [.CPItest_divr_0]
        fdivrp %ST(1)
        ret

We now generate this:

test_divr:
        fld QWORD PTR [%ESP + 4]
        fdivr QWORD PTR [.CPItest_divr_0]
        ret

This code desperately needs refactoring, which will come in the next
patch.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12841 91177308-0d34-0410-b5e6-96231b3b80d8

Restructure the mul/div/rem handling code to follow the pattern the other
instructions use.  This doesn't change any functionality except that long
constant expressions of these operations will now magically start working.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12840 91177308-0d34-0410-b5e6-96231b3b80d8

Codegen FP adds and subtracts with a constant more efficiently, generating:

        fld QWORD PTR [%ESP + 4]
        fadd QWORD PTR [.CPItest_add_0]

instead of:

        fld QWORD PTR [%ESP + 4]
        fld QWORD PTR [.CPItest_add_0]
        faddp %ST(1)

I also intend to do this for mul & div, but it appears that I have to
refactor a bit of code before I can do so.

This is tested by: test/Regression/CodeGen/X86/fp_constant_op.llx

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12839 91177308-0d34-0410-b5e6-96231b3b80d8

Add some new instructions

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12838 91177308-0d34-0410-b5e6-96231b3b80d8

New testcase

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12837 91177308-0d34-0410-b5e6-96231b3b80d8

Relax assertion to make this function work with a broader class of instructions

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12836 91177308-0d34-0410-b5e6-96231b3b80d8

Two changes:
  1. If an incoming argument is dead, don't load it from the stack
  2. Do not code gen noop copies at all (ie, cast int -> uint), not even to
     a move.  This should reduce register pressure for allocators that are
     unable to coallesce away these copies in some cases.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12835 91177308-0d34-0410-b5e6-96231b3b80d8

Add another variant of the testcase

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12834 91177308-0d34-0410-b5e6-96231b3b80d8

operator new & operator new[] do not kill any legal memory locations.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12833 91177308-0d34-0410-b5e6-96231b3b80d8

new testcase

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12832 91177308-0d34-0410-b5e6-96231b3b80d8

Allow clients to be more efficient.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12831 91177308-0d34-0410-b5e6-96231b3b80d8

Make comments above APIs reflect what they should do.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12830 91177308-0d34-0410-b5e6-96231b3b80d8

New method to allow more efficient clients

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12829 91177308-0d34-0410-b5e6-96231b3b80d8

Fix a bug in my select transformation

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12826 91177308-0d34-0410-b5e6-96231b3b80d8

Add a missing break, which caused a crash in an obscure situation

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12825 91177308-0d34-0410-b5e6-96231b3b80d8

Update the value numbering interface.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12824 91177308-0d34-0410-b5e6-96231b3b80d8

Note to self: SAVE FILES!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12823 91177308-0d34-0410-b5e6-96231b3b80d8

Add an interface to update value numbering

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12822 91177308-0d34-0410-b5e6-96231b3b80d8

Implement InstCombine/select.ll:test13*

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12821 91177308-0d34-0410-b5e6-96231b3b80d8

New testcases

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12820 91177308-0d34-0410-b5e6-96231b3b80d8

Implement InstCombine/add.ll:test20
Canonicalize add of sign bit constant into a xor

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12819 91177308-0d34-0410-b5e6-96231b3b80d8

New testcase

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12818 91177308-0d34-0410-b5e6-96231b3b80d8

Rewrite the GCSE pass to be *substantially* simpler, a bit more efficient,
and a bit more powerful

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12817 91177308-0d34-0410-b5e6-96231b3b80d8

Fix spurious warning in release mode

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12816 91177308-0d34-0410-b5e6-96231b3b80d8

Silence a spurious warning

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12815 91177308-0d34-0410-b5e6-96231b3b80d8

Simplify code a bit, and fix a bug that was breaking perlbmk

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12814 91177308-0d34-0410-b5e6-96231b3b80d8

Fix a bug in my checkin last night that was breaking programs using invoke.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12813 91177308-0d34-0410-b5e6-96231b3b80d8

Fix previous patch

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12811 91177308-0d34-0410-b5e6-96231b3b80d8

Correctly update counters

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12810 91177308-0d34-0410-b5e6-96231b3b80d8

Add note

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12809 91177308-0d34-0410-b5e6-96231b3b80d8

Add a couple of more functions that cannot access memory (the intrinsics) and
don't write to memory

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12808 91177308-0d34-0410-b5e6-96231b3b80d8

Simplify code a bit, and use alias analysis to allow us to delete unused
call and invoke instructions that are known to not write to memory.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12807 91177308-0d34-0410-b5e6-96231b3b80d8

New testcases

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12806 91177308-0d34-0410-b5e6-96231b3b80d8

Clarify interface

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12805 91177308-0d34-0410-b5e6-96231b3b80d8

Create the output directory if it's not already there

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12804 91177308-0d34-0410-b5e6-96231b3b80d8

Simplify cfg now eliminates all of the branches in this testcase

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12803 91177308-0d34-0410-b5e6-96231b3b80d8

Another testcase

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12802 91177308-0d34-0410-b5e6-96231b3b80d8

Testcase to make sure we can apply the shift to the operands of the select,
eliminating the shifts

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12801 91177308-0d34-0410-b5e6-96231b3b80d8

Implement select.ll:test12*

This transforms code like this:

   %C = or %A, %B
   %D = select %cond, %C, %A
into:
   %C = select %cond, %B, 0
   %D = or %A, %C

Since B is often a constant, the select can often be eliminated.  In any case,
this reduces the usage count of A, allowing subsequent optimizations to happen.

This xform applies when the operator is any of:
  add, sub, mul, or, xor, and, shl, shr

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12800 91177308-0d34-0410-b5e6-96231b3b80d8

Add testcases for harder combining cases.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12799 91177308-0d34-0410-b5e6-96231b3b80d8