Commit Graph

23 Commits

Author SHA1 Message Date
David Majnemer 33b6f82e72 [InstCombine] Generalize sub of selects optimization to all BinaryOperators
This exposes further optimization opportunities if the selects are
correlated.

llvm-svn: 242235
2015-07-14 22:39:23 +00:00
David Majnemer 4c3753c4d4 [InstCombine] Don't eagerly propagate nsw for A*B+A*C => A*(B+C)
InstCombine transforms A *nsw B +nsw A *nsw C to A *nsw (B + C).
This is incorrect -- e.g. if A = -1, B = 1, C = INT_SMAX. Then
nothing in the LHS overflows, but the multiplication in RHS overflows.

We need to first make sure that we won't multiple by INT_SMAX + 1.

Test case `add_of_mul` contributed by Sanjoy Das.

This fixes PR23635.

Differential Revision: http://reviews.llvm.org/D9629

llvm-svn: 238066
2015-05-22 23:02:11 +00:00
Duncan P. N. Exon Smith be7ea19b58 IR: Make metadata typeless in assembly
Now that `Metadata` is typeless, reflect that in the assembly.  These
are the matching assembly changes for the metadata/value split in
r223802.

  - Only use the `metadata` type when referencing metadata from a call
    intrinsic -- i.e., only when it's used as a `Value`.

  - Stop pretending that `ValueAsMetadata` is wrapped in an `MDNode`
    when referencing it from call intrinsics.

So, assembly like this:

    define @foo(i32 %v) {
      call void @llvm.foo(metadata !{i32 %v}, metadata !0)
      call void @llvm.foo(metadata !{i32 7}, metadata !0)
      call void @llvm.foo(metadata !1, metadata !0)
      call void @llvm.foo(metadata !3, metadata !0)
      call void @llvm.foo(metadata !{metadata !3}, metadata !0)
      ret void, !bar !2
    }
    !0 = metadata !{metadata !2}
    !1 = metadata !{i32* @global}
    !2 = metadata !{metadata !3}
    !3 = metadata !{}

turns into this:

    define @foo(i32 %v) {
      call void @llvm.foo(metadata i32 %v, metadata !0)
      call void @llvm.foo(metadata i32 7, metadata !0)
      call void @llvm.foo(metadata i32* @global, metadata !0)
      call void @llvm.foo(metadata !3, metadata !0)
      call void @llvm.foo(metadata !{!3}, metadata !0)
      ret void, !bar !2
    }
    !0 = !{!2}
    !1 = !{i32* @global}
    !2 = !{!3}
    !3 = !{}

I wrote an upgrade script that handled almost all of the tests in llvm
and many of the tests in cfe (even handling many `CHECK` lines).  I've
attached it (or will attach it in a moment if you're speedy) to PR21532
to help everyone update their out-of-tree testcases.

This is part of PR21532.

llvm-svn: 224257
2014-12-15 19:07:53 +00:00
David Majnemer 80c8f627db InstCombine: Preserve nsw when folding X*(2^C) -> X << C
llvm-svn: 222606
2014-11-22 04:52:55 +00:00
David Majnemer 3cac85e071 InstCombine: mul to shl shouldn't preserve nsw
consider:
mul i32 nsw %x, -2147483648

this instruction will not result in poison if %x is 1

however, if we transform this into:
shl i32 nsw %x, 31

then we will be generating poison because we just shifted into the sign
bit.

This fixes PR21242.

llvm-svn: 219566
2014-10-11 10:19:52 +00:00
David Majnemer ab07f00c64 InstCombine: Combine (add (and %a, %b) (or %a, %b)) to (add %a, %b)
What follows bellow is a correctness proof of the transform using CVC3.

$ < t.cvc
A, B : BITVECTOR(32);

QUERY BVPLUS(32, A & B, A | B) = BVPLUS(32, A, B);

$ cvc3 < t.cvc
Valid.

llvm-svn: 215400
2014-08-11 22:32:02 +00:00
Dinesh Dwivedi adc07739a9 Added instruction combine to transform few more negative values addition to subtraction (Part 3)
This patch enables transforms for

(x + (~(y | c) + 1) --> x - (y | c) if c is odd

Differential Revision: http://reviews.llvm.org/D4210

llvm-svn: 211881
2014-06-27 07:47:35 +00:00
Dinesh Dwivedi a716173581 Added instruction combine to transform few more negative values addition to subtraction (Part 2)
This patch enables transforms for

(x + (~(y | c) + 1)   -->   x - (y | c) if c is even

Differential Revision: http://reviews.llvm.org/D4209

llvm-svn: 211765
2014-06-26 05:40:22 +00:00
Jingyue Wu 37fcb5919d [ValueTracking] Extend range metadata to call/invoke
Summary:
With this patch, range metadata can be added to call/invoke including
IntrinsicInst. Previously, it could only be added to load.

Rename computeKnownBitsLoad to computeKnownBitsFromRangeMetadata because
range metadata is not only used by load.

Update the language reference to reflect this change.

Test Plan:
Add several tests in range-2.ll to confirm the verifier is happy with
having range metadata on call/invoke.

Add two tests in AddOverFlow.ll to confirm annotating range metadata to
call/invoke can benefit InstCombine.

Reviewers: meheff, nlewycky, reames, hfinkel, eliben

Reviewed By: eliben

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D4187

llvm-svn: 211281
2014-06-19 16:50:16 +00:00
Dinesh Dwivedi 562fd7534c Added instruction combine to transform few more negative values addition to subtraction (Part 1)
This patch enables transforms for following patterns.
  (x + (~(y & c) + 1)   -->   x - (y & c)
  (x + (~((y >> z) & c) + 1)   -->   x - ((y>>z) & c)

Differential Revision: http://reviews.llvm.org/D3733

llvm-svn: 211266
2014-06-19 10:36:52 +00:00
Dinesh Dwivedi b62e52e1b5 Refactored and updated SimplifyUsingDistributiveLaws() to
* Find factorization opportunities using identity values.
 * Find factorization opportunities by treating shl(X, C) as mul (X, shl(C))
 * Keep NSW flag while simplifying instruction using factorization.

This fixes PR19263.

Differential Revision: http://reviews.llvm.org/D3799

llvm-svn: 211261
2014-06-19 08:29:18 +00:00
Rafael Espindola c286f4bf2a Add a testcase where there is an overflow when combining two constants.
I noticed that a proposed optimization would have prevented this.

llvm-svn: 210287
2014-06-05 21:29:49 +00:00
Benjamin Kramer 72196f3ae5 InstCombine: Teach most integer add/sub/mul/div combines how to deal with vectors.
llvm-svn: 199602
2014-01-19 15:24:22 +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
Chris Lattner 5592071768 preserve NUW/NSW when transforming add x,x
llvm-svn: 125711
2011-02-17 02:23:02 +00:00
Chris Lattner 0ad64291d8 filecheckize
llvm-svn: 125710
2011-02-17 02:21:03 +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
Dan Gohman 33a3fd0b9c Revert the addition of hasNoPointerOverflow to GEPOperator.
Getelementptrs that are defined to wrap are virtually useless to
optimization, and getelementptrs that are undefined on any kind
of overflow are too restrictive -- it's difficult to ensure that
all intermediate addresses are within bounds. I'm going to take
a different approach.

Remove a few optimizations that depended on this flag.

llvm-svn: 76437
2009-07-20 17:43:30 +00:00
Chris Lattner fc365b60dc be more aggressive about transforming add -> or when the operands have no
intersecting bits.  This triggers all over the place, for example in lencode,
with adds of stuff like:

	%tmp580 = mul i32 %tmp579, 2	
	%tmp582 = and i32 %b8, 1
and

	%tmp28 = shl i32 %abs.i, 1		
	%sign.0 = select i1 %tmp23, i32 1, i32 0
and
	%tmp344 = shl i32 %tmp343, 2	
	%tmp346 = and i32 %tmp96, 3

etc.

llvm-svn: 51263
2008-05-19 20:01:56 +00:00
Chris Lattner 2940c5c56d Implement PR1795, an instcombine hack for forming GEPs with integer pointer arithmetic.
llvm-svn: 45745
2008-01-08 07:23:51 +00:00
Reid Spencer 6e87ec4351 For PR1319:
Remove && from the end of the lines to prevent tests from throwing run
lines into the background. Also, clean up places where the same command
is run multiple times by using a temporary file.

llvm-svn: 36142
2007-04-16 17:36:08 +00:00
Chris Lattner 3a8b0c7607 new testcase
llvm-svn: 34918
2007-03-05 00:01:38 +00:00