Commit Graph

21809 Commits

Author SHA1 Message Date
David Blaikie b461468958 DebugInfo: Improve type safety and simplify some subprogram finalization code
This probably ended up this way aften the subprogram<>function link
inversion and debug info metadata schema changes.

llvm-svn: 289697
2016-12-14 19:38:39 +00:00
Andrew Kaylor ce3bcae632 [WinEH] Avoid holding references to BlockColor (DenseMap) entries while inserting new elements
Differential Revision: https://reviews.llvm.org/D27693

llvm-svn: 289694
2016-12-14 19:30:18 +00:00
Nirav Dave f5bf03c7ef Revert "In visitSTORE, always use FindBetterChain, rather than only when UseAA is enabled."
Reverting due to ARM MCJIT and MIPS LLD error.

This reverts commit r289659.

llvm-svn: 289667
2016-12-14 16:43:44 +00:00
Nirav Dave 8527ab0ad2 In visitSTORE, always use FindBetterChain, rather than only when UseAA is enabled.
Retrying after fixing after removing load-store factoring through
token factors in favor of improved token factor operand pruning

Simplify Consecutive Merge Store Candidate Search

Now that address aliasing is much less conservative, push through
simplified store merging search which only checks for parallel stores
through the chain subgraph. This is cleaner as the separation of
non-interfering loads/stores from the store-merging logic.

Whem merging stores, search up the chain through a single load, and
finds all possible stores by looking down from through a load and a
TokenFactor to all stores visited. This improves the quality of the
output SelectionDAG and generally the output CodeGen (with some
exceptions).

Additional Minor Changes:

   1. Finishes removing unused AliasLoad code
   2. Unifies the the chain aggregation in the merged stores across
      code paths
   3. Re-add the Store node to the worklist after calling
      SimplifyDemandedBits.
   4. Increase GatherAllAliasesMaxDepth from 6 to 18. That number is
      arbitrary, but seemed sufficient to not cause regressions in
      tests.

This finishes the change Matt Arsenault started in r246307 and
jyknight's original patch.

Many tests required some changes as memory operations are now
reorderable. Some tests relying on the order were changed to use
volatile memory operations

Noteworthy tests:

    CodeGen/AArch64/argument-blocks.ll -
      It's not entirely clear what the test_varargs_stackalign test is
      supposed to be asserting, but the new code looks right.

    CodeGen/AArch64/arm64-memset-inline.lli -
    CodeGen/AArch64/arm64-stur.ll -
    CodeGen/ARM/memset-inline.ll -

      The backend now generates *worse* code due to store merging
      succeeding, as we do do a 16-byte constant-zero store efficiently.

    CodeGen/AArch64/merge-store.ll -
      Improved, but there still seems to be an extraneous vector insert
      from an element to itself?

    CodeGen/PowerPC/ppc64-align-long-double.ll -
      Worse code emitted in this case, due to the improved store->load
      forwarding.

    CodeGen/X86/dag-merge-fast-accesses.ll -
    CodeGen/X86/MergeConsecutiveStores.ll -
    CodeGen/X86/stores-merging.ll -
    CodeGen/Mips/load-store-left-right.ll -
      Restored correct merging of non-aligned stores

    CodeGen/AMDGPU/promote-alloca-stored-pointer-value.ll -
      Improved. Correctly merges buffer_store_dword calls

    CodeGen/AMDGPU/si-triv-disjoint-mem-access.ll -
      Improved. Sidesteps loading a stored value and
      merges two stores

    CodeGen/X86/pr18023.ll -
      This test has been removed, as it was asserting incorrect
      behavior. Non-volatile stores *CAN* be moved past volatile loads,
      and now are.

    CodeGen/X86/vector-idiv.ll -
    CodeGen/X86/vector-lzcnt-128.ll -
      It's basically impossible to tell what these tests are actually
      testing. But, looks like the code got better due to the memory
      operations being recognized as non-aliasing.

    CodeGen/X86/win32-eh.ll -
      Both loads of the securitycookie are now merged.

Reviewers: arsenm, hfinkel, tstellarAMD, jyknight, nhaehnle

Subscribers: wdng, nhaehnle, nemanjai, arsenm, weimingz, niravd, RKSimon, aemerson, qcolombet, dsanders, resistor, tstellarAMD, t.p.northover, spatel

Differential Revision: https://reviews.llvm.org/D14834

llvm-svn: 289659
2016-12-14 15:44:26 +00:00
Simon Pilgrim 05ab8ffc7e [DAGCombiner] Try to use SelectionDAG::isKnownToBeAPowerOfTwo instead of just APInt::isPowerOf2
Generalize sdiv/udiv/srem/urem combines using APInt::isPowerOf2, which only works for const/splat-const values, to call SelectionDAG::isKnownToBeAPowerOfTwo instead which recognises many more cases.

Added a DAGCombiner::BuildLogBase2 helper since PowerOf2 combines often involve taking the log2 of such a value.

Differential Revision: https://reviews.llvm.org/D27714

llvm-svn: 289654
2016-12-14 15:08:13 +00:00
Stephan Bergmann 17c7f70362 Replace APFloatBase static fltSemantics data members with getter functions
At least the plugin used by the LibreOffice build
(<https://wiki.documentfoundation.org/Development/Clang_plugins>) indirectly
uses those members (through inline functions in LLVM/Clang include files in turn
using them), but they are not exported by utils/extract_symbols.py on Windows,
and accessing data across DLL/EXE boundaries on Windows is generally
problematic.

Differential Revision: https://reviews.llvm.org/D26671

llvm-svn: 289647
2016-12-14 11:57:17 +00:00
Artur Pilipenko f3ee444010 Add a couple of assertions to the load combine code introduced by r289538
llvm-svn: 289646
2016-12-14 11:55:47 +00:00
Paul Robinson 8fec3da00c [DWARF] Preserve column number when emitting 'line 0' record
Follow-up to r289256, address a FIXME to avoid resetting the column
number. This reduced .debug_line by 2.6% in a RelWithDebInfo
self-build of clang.

llvm-svn: 289620
2016-12-14 00:27:35 +00:00
Alina Sbirlea 77c5eaaeda Generalize strided store pattern in interleave access pass
Summary:
This patch aims to generalize matching of the strided store accesses to more general masks.
The more general rule is to have consecutive accesses based on the stride:
[x, y, ... z, x+1, y+1, ...z+1, x+2, y+2, ...z+2, ...]
All elements in the masks need not form a contiguous space, there may be gaps.
As before, undefs are allowed and filled in with adjacent element loads.

Reviewers: HaoLiu, mssimpso

Subscribers: mkuper, delena, llvm-commits

Differential Revision: https://reviews.llvm.org/D23646

llvm-svn: 289573
2016-12-13 19:32:36 +00:00
Artur Pilipenko 469fcd2afd Use more detailed assertion messages in the code introduced by r289538
llvm-svn: 289545
2016-12-13 16:26:15 +00:00
Artur Pilipenko 79d1255e26 Fix a buildbot failure introduced by r289538
Build failed because of unused variable in product mode.

llvm-svn: 289540
2016-12-13 14:55:31 +00:00
Artur Pilipenko c93cc5955f [DAGCombiner] Match load by bytes idiom and fold it into a single load
Match a pattern where a wide type scalar value is loaded by several narrow loads and combined by shifts and ors. Fold it into a single load or a load and a bswap if the targets supports it.

Assuming little endian target:
  i8 *a = ...
  i32 val = a[0] | (a[1] << 8) | (a[2] << 16) | (a[3] << 24)
=>
  i32 val = *((i32)a)

  i8 *a = ...
  i32 val = (a[0] << 24) | (a[1] << 16) | (a[2] << 8) | a[3]
=>
  i32 val = BSWAP(*((i32)a))

This optimization was discussed on llvm-dev some time ago in "Load combine pass" thread. We came to the conclusion that we want to do this transformation late in the pipeline because in presence of atomic loads load widening is irreversible transformation and it might hinder other optimizations.

Eventually we'd like to support folding patterns like this where the offset has a variable and a constant part:
  i32 val = a[i] | (a[i + 1] << 8) | (a[i + 2] << 16) | (a[i + 3] << 24)

Matching the pattern above is easier at SelectionDAG level since address reassociation has already happened and the fact that the loads are adjacent is clear. Understanding that these loads are adjacent at IR level would have involved looking through geps/zexts/adds while looking at the addresses.

The general scheme is to match OR expressions by recursively calculating the origin of individual bits which constitute the resulting OR value. If all the OR bits come from memory verify that they are adjacent and match with little or big endian encoding of a wider value. If so and the load of the wider type (and bswap if needed) is allowed by the target generate a load and a bswap if needed.

Reviewed By: hfinkel, RKSimon, filcab

Differential Revision: https://reviews.llvm.org/D26149

llvm-svn: 289538
2016-12-13 14:21:14 +00:00
Artur Pilipenko 01e86444a0 Move BaseIndexOffset in DAGCombiner.cpp so it will be available for the upcoming user
llvm-svn: 289537
2016-12-13 14:16:02 +00:00
Simon Pilgrim 9dc67c0101 [SelectionDAG] computeKnownBits - simplified knownbits sign extension. NFCI.
We don't need to extract+test the sign bit of the known ones/zeros, we can use sext which will handle all of this.

llvm-svn: 289534
2016-12-13 13:36:27 +00:00
Diana Picus 2d9adbf524 [GlobalISel] Move extendRegister where it belongs. NFCI
Apparently I missed this one when I moved ValueHandler back in r288658. Sorry!

llvm-svn: 289528
2016-12-13 10:46:12 +00:00
Philip Reames 1f1bbac8da [peephole] Enhance folding logic to work for STATEPOINTs
The general idea here is to get enough of the existing restrictions out of the way that the already existing folding logic in foldMemoryOperand can kick in for STATEPOINTs and fold references to immutable stack slots. The key changes are:

    Support for folding multiple operands at once which reference the same load
    Support for folding multiple loads into a single instruction
    Walk all the operands of the instruction for varidic instructions (this is a bug fix!)

Once this lands, I'll post another patch which refactors the TII interface here. There's nothing actually x86 specific about the x86 code used here.

Differential Revision: https://reviews.llvm.org/D24103

llvm-svn: 289510
2016-12-13 01:38:41 +00:00
Philip Reames 51387a8c28 [Statepoints] Reuse stack slots more than once within a basic block
The stack slot reuse code had a really amusing bug. We ended up only reusing a stack slot exact once (initial use + reuse) within a basic block. If we had a third statepoint to process, we ended up allocating a new set of stack slots. If we crossed a basic block boundary, the set got cleared. As a result, code which is invoke heavy doesn't see the problem, but multiple calls within a basic block does. Net result: as we optimize invokes into calls, lowering gets worse.

The root error here is that the bitmap uses by the custom allocator wasn't kept in sync. The result was that we ended up resizing the bitmap on the next statepoint (to handle the cross block case), reset the bit once, but then never reset it again.

Differential Revision: https://reviews.llvm.org/D25243

llvm-svn: 289509
2016-12-13 01:21:15 +00:00
Andrew Kaylor ff6a1edfa8 Avoid infinite loops in branch folding
Differential Revision: https://reviews.llvm.org/D27582

llvm-svn: 289486
2016-12-12 23:05:38 +00:00
Paul Robinson ac7fe5e0c4 Recommit r288212: Emit 'no line' information for interesting 'orphan' instructions.
DWARF specifies that "line 0" really means "no appropriate source
location" in the line table.  By default, use this for branch targets
and some other cases that have no specified source location, to
prevent inheriting unfortunate line numbers from physically preceding
instructions (which might be from completely unrelated source).

Updated patch allows enabling or suppressing this behavior for all
unspecified source locations.

Differential Revision: http://reviews.llvm.org/D24180

llvm-svn: 289468
2016-12-12 20:49:11 +00:00
Geoff Berry d73420d591 [LiveRangeEdit] Add assert string and descriptive comment.
llvm-svn: 289456
2016-12-12 19:12:41 +00:00
Simon Pilgrim 040a36c176 [SelectionDAG] Add support for EXTRACT_SUBVECTOR to ComputeNumSignBits
Pre-commit as discussed on D27657

llvm-svn: 289425
2016-12-12 10:29:43 +00:00
Sebastian Pop e08d9c7c87 instr-combiner: sum up all latencies of the transformed instructions
We have found that -- when the selected subarchitecture has a scheduling model
and we are not optimizing for size -- the machine-instruction combiner uses a
too-simple algorithm to compute the cost of one of the two alternatives [before
and after running a combining pass on a section of code], and therefor it throws
away the combination results too often.

This fix has the potential to help any ISA with the potential to combine
instructions and for which at least one subarchitecture has a scheduling model.
As of now, this is only known to definitely affect AArch64 subarchitectures with
a scheduling model.

Regression tested on AMD64/GNU-Linux, new test case tested to fail on an
unpatched compiler and pass on a patched compiler.

Patch by Abe Skolnik and Sebastian Pop.

llvm-svn: 289399
2016-12-11 19:39:32 +00:00
Simon Pilgrim 54945a12ec [SelectionDAG] Add ability for computeKnownBits to peek through bitcasts from 'large element' scalar/vector to 'small element' vector.
Extension to D27129 which already supported bitcasts from 'small element' vector to 'large element' scalar/vector types.

llvm-svn: 289329
2016-12-10 17:00:00 +00:00
Adrian Prantl 8fafb8d378 Fix LLVM's use of DW_OP_bit_piece in DWARF expressions.
LLVM's use of DW_OP_bit_piece is incorrect and a based on a
misunderstanding of the wording in the DWARF specification. The offset
argument of DW_OP_bit_piece refers to the offset into the location
that is on the top of the DWARF expression stack, and not an offset
into the source variable. This has since also been clarified in the
DWARF specification.

This patch fixes all uses of DW_OP_bit_piece to emit the correct
offset and simplifies the DwarfExpression class to semi-automaticaly
emit empty DW_OP_pieces to adjust the offset of the source variable,
thus simplifying the code using DwarfExpression.

While this is an incompatible bugfix, in practice I don't expect this
to be much of a problem since LLVM's old interpretation and the
correct interpretation of DW_OP_bit_piece differ only when there are
gaps in the fragmented locations of the described variables or if
individual fragments are smaller than a byte. LLDB at least won't
interpret locations with gaps in them because is has no way to present
undefined bits in a variable, and there is a high probability that an
old-form expression will be malformed when interpreted correctly,
because the DW_OP_bit_piece offset will be outside of the location at
the top of the stack.

As a nice side-effect, this patch enables us to use a more efficient
encoding for subregisters: In order to express a sub-register at a
non-zero offset we now use a DW_OP_bit_piece instead of shifting the
value into place manually.

This patch also adds missing test coverage for code paths that weren't
exercised before.

<rdar://problem/29335809>
Differential Revision: https://reviews.llvm.org/D27550

llvm-svn: 289266
2016-12-09 20:43:40 +00:00
Paul Robinson 4fa7b57a1f [DWARF] Suppress .loc directives from CFI instructions
Like DBG_VALUE, these emit nothing to the .text section, and sometimes
have no source location specified.  Just ignore them.

Differential Revision: http://reviews.llvm.org/D27492

llvm-svn: 289256
2016-12-09 19:15:32 +00:00
Simon Pilgrim 017b7a71d8 [SelectionDAG] Add knownbits support for EXTRACT_VECTOR_ELT opcodes (REAPPLIED)
Reapplied with fix for PR31323 - X86 SSE2 vXi16 multiplies for illegal types were creating CONCAT_VECTORS nodes with vector inputs that might not total the number of elements in the result type.

llvm-svn: 289232
2016-12-09 17:53:11 +00:00
Matt Arsenault 38d8ed2b75 AMDGPU: Fix i128 mul
llvm-svn: 289231
2016-12-09 17:49:14 +00:00
Nirav Dave bedb5d906c Revert "In visitSTORE, always use FindBetterChain, rather than only when UseAA is enabled."
This reverts commit r289221 which appears to be triggering an assertion

llvm-svn: 289226
2016-12-09 17:18:24 +00:00
Nirav Dave fd51ff4fd8 In visitSTORE, always use FindBetterChain, rather than only when UseAA is enabled.
Retrying after fixing overly aggressive load-store forwarding optimization.

Simplify Consecutive Merge Store Candidate Search

Now that address aliasing is much less conservative, push through
simplified store merging search which only checks for parallel stores
through the chain subgraph. This is cleaner as the separation of
non-interfering loads/stores from the store-merging logic.

Whem merging stores, search up the chain through a single load, and
finds all possible stores by looking down from through a load and a
TokenFactor to all stores visited. This improves the quality of the
output SelectionDAG and generally the output CodeGen (with some
exceptions).

Additional Minor Changes:

   1. Finishes removing unused AliasLoad code
   2. Unifies the the chain aggregation in the merged stores across
      code paths
   3. Re-add the Store node to the worklist after calling
      SimplifyDemandedBits.
   4. Increase GatherAllAliasesMaxDepth from 6 to 18. That number is
      arbitrary, but seemed sufficient to not cause regressions in
      tests.

This finishes the change Matt Arsenault started in r246307 and
jyknight's original patch.

Many tests required some changes as memory operations are now
reorderable. Some tests relying on the order were changed to use
volatile memory operations

Noteworthy tests:

    CodeGen/AArch64/argument-blocks.ll -
      It's not entirely clear what the test_varargs_stackalign test is
      supposed to be asserting, but the new code looks right.

    CodeGen/AArch64/arm64-memset-inline.lli -
    CodeGen/AArch64/arm64-stur.ll -
    CodeGen/ARM/memset-inline.ll -

      The backend now generates *worse* code due to store merging
      succeeding, as we do do a 16-byte constant-zero store efficiently.

    CodeGen/AArch64/merge-store.ll -
      Improved, but there still seems to be an extraneous vector insert
      from an element to itself?

    CodeGen/PowerPC/ppc64-align-long-double.ll -
      Worse code emitted in this case, due to the improved store->load
      forwarding.

    CodeGen/X86/dag-merge-fast-accesses.ll -
    CodeGen/X86/MergeConsecutiveStores.ll -
    CodeGen/X86/stores-merging.ll -
    CodeGen/Mips/load-store-left-right.ll -
      Restored correct merging of non-aligned stores

    CodeGen/AMDGPU/promote-alloca-stored-pointer-value.ll -
      Improved. Correctly merges buffer_store_dword calls

    CodeGen/AMDGPU/si-triv-disjoint-mem-access.ll -
      Improved. Sidesteps loading a stored value and
      merges two stores

    CodeGen/X86/pr18023.ll -
      This test has been removed, as it was asserting incorrect
      behavior. Non-volatile stores *CAN* be moved past volatile loads,
      and now are.

    CodeGen/X86/vector-idiv.ll -
    CodeGen/X86/vector-lzcnt-128.ll -
      It's basically impossible to tell what these tests are actually
      testing. But, looks like the code got better due to the memory
      operations being recognized as non-aliasing.

    CodeGen/X86/win32-eh.ll -
      Both loads of the securitycookie are now merged.

Reviewers: arsenm, hfinkel, tstellarAMD, jyknight, nhaehnle

Subscribers: wdng, nhaehnle, nemanjai, arsenm, weimingz, niravd, RKSimon, aemerson, qcolombet, dsanders, resistor, tstellarAMD, t.p.northover, spatel

Differential Revision: https://reviews.llvm.org/D14834

llvm-svn: 289221
2016-12-09 16:15:12 +00:00
Simon Pilgrim b9eb99f570 Use SelectionDAG.getSplatBuildVector helper. NFCI.
llvm-svn: 289220
2016-12-09 16:01:50 +00:00
Simon Pilgrim bf9c0e7434 [SelectionDAG] Use SelectionDAG.getBuildVector helper. NFCI.
Makes interception of BUILD_VECTOR creation easier for debugging.

llvm-svn: 289218
2016-12-09 15:23:41 +00:00
Simon Pilgrim 15f1f828b5 [SelectionDAG] Add additional checks to CONCAT_VECTORS creation
Part of the work for PR31323 - add extra asserts checking that the input vectors are of consistent type and result in the correct number of vector elements.

llvm-svn: 289214
2016-12-09 14:27:52 +00:00
Benjamin Kramer eedc4059c3 Plug another leak in the DWARF unittests, DIEInlineStrings are never destroyed.
llvm-svn: 289208
2016-12-09 13:33:41 +00:00
Simon Pilgrim e4050a2961 [SelectionDAG] Add partial BITCAST support to computeKnownBits
Adds support for bitcasting a little endian 'small element' vector to 'large element' scalar/vector (e.g. v16i8 to v4i32 or v2i32 to i64), which is required for PR30845. We extract the knownbits for each 'small element' part and concatenate the results together.

We can add support for big endian and 'large element' scalar/vector to 'small element' vector bitcasting once we have test cases for them.

Differential Revision: https://reviews.llvm.org/D27129

llvm-svn: 289200
2016-12-09 10:13:45 +00:00
Daniel Jasper f51e05ffbc Revert "[SelectionDAG] Add knownbits support for EXTRACT_VECTOR_ELT opcodes"
This reverts commit r288916 as it is currently causing a crasher in
Halide. Reproducer on llvm.org/PR31323. While it might be that halide is
generating invalid IR, llc shouldn't crash.

llvm-svn: 289194
2016-12-09 09:04:51 +00:00
Tim Northover b58346f2f2 GlobalISel: fall back gracefully for debug intrinsics.
Supporting them properly is a reasonably complex chunk of work, so to allow bot
testing before then we should at least be able to fall back to DAG ISel.

llvm-svn: 289150
2016-12-08 22:44:13 +00:00
Tim Northover 1e656ec137 GlobalISel: factor overflow handling into separate function. NFC.
llvm-svn: 289149
2016-12-08 22:44:00 +00:00
Reid Kleckner 785e7d282c Don't emit .seh_handler directives for any cleanup funclets
We were falsely claiming that we had an LSDA for the relevant EH
personality before this change, which could lead to the EH machinery
interpreting random adjacent data as an LSDA.

Fixes PR31317

This change is safe because cleanups can't contain exception handlers
today. We do these things to maintain that invariant:
- C++ destructors are naturally out-of-line
- __finally blocks are outlined in clang
- LLVM's inliner will not inline EH constructs into cleanups

llvm-svn: 289101
2016-12-08 20:38:46 +00:00
NAKAMURA Takumi 689493bb12 Prune unused libdeps.
llvm-svn: 289060
2016-12-08 15:28:02 +00:00
Nicolai Haehnle f08dc90253 [SelectionDAG] Add expansion and promotion of [US]MUL_LOHI
Summary:
Most targets set the action for these nodes to Expand even though there
isn't actually any code for them in ExpandNode. Instead, targets simply
relied on the fact that no code generates these nodes as long as the
nodes aren't legal or custom.

However, generating these nodes can be useful e.g. for divide-by-constant
in wider integer types.

Expand of [US]MUL_LOHI will use MULH[US] when legal or custom, and
a sequence of half-width multiplications otherwise. Promote uses a wider
multiply.

This patch intends to not change the generated code, but indirect effects
are possible since expansions/promotions that were previously done in
DAGCombine may now be done in LegalizeDAG.

See D24822 for a change that actually uses the new expansion.

Reviewers: spatel, bkramer, venkatra, efriedma, hfinkel, ast, nadav, tstellarAMD

Subscribers: arsenm, jyknight, nemanjai, wdng, nhaehnle, llvm-commits

Differential Revision: https://reviews.llvm.org/D24956

llvm-svn: 289050
2016-12-08 14:08:14 +00:00
Daniel Jasper 0f77869d58 Move DwarfGenerator.cpp to unittests
So far it creates a test helper and so it should be moved there. It also
create a layering cycle between CodeGen and CodeGen/AsmPrinter, which
should be avoided.

Review: https://reviews.llvm.org/D27570
llvm-svn: 289044
2016-12-08 12:45:29 +00:00
Simon Pilgrim 413c8e217f Wdocumentation fix
llvm-svn: 289038
2016-12-08 10:41:41 +00:00
Keno Fischer d4ea4c18f1 Revert "[CodeGen] Fix invalid DWARF info on Win64"
Appears to break on build bots. Reverting pending investigation.

llvm-svn: 289014
2016-12-08 01:56:23 +00:00
Keno Fischer 460218fb7d [CodeGen] Fix invalid DWARF info on Win64
The relocations for `DIEEntry::EmitValue` were wrong for Win64
(emitting FK_Data_4 instead of FK_SecRel_4). This corrects that
oversight so that the DWARF data is correct in Win64 COFF files.

Fixes PR15393.

Patch by Jameson Nash <jameson@juliacomputing.com> based on a patch
by David Majnemer.

Differential Revision: https://reviews.llvm.org/D21731

llvm-svn: 289013
2016-12-08 01:40:21 +00:00
Greg Clayton 3462a420d1 Make a DWARF generator so we can unit test DWARF APIs with gtest.
The only tests we have for the DWARF parser are the tests that use llvm-dwarfdump and expect output from textual dumps.

More DWARF parser modification are coming in the next few weeks and I wanted to add tests that can verify that we can encode and decode all form types, as well as test some other basic DWARF APIs where we ask DIE objects for their children and siblings.

DwarfGenerator.cpp was added in the lib/CodeGen directory. This file contains the code necessary to easily create DWARF for tests:

dwarfgen::Generator DG;
Triple Triple("x86_64--");
bool success = DG.init(Triple, Version);
if (!success)
  return;
dwarfgen::CompileUnit &CU = DG.addCompileUnit();
dwarfgen::DIE CUDie = CU.getUnitDIE();

CUDie.addAttribute(DW_AT_name, DW_FORM_strp, "/tmp/main.c");
CUDie.addAttribute(DW_AT_language, DW_FORM_data2, DW_LANG_C);

dwarfgen::DIE SubprogramDie = CUDie.addChild(DW_TAG_subprogram);
SubprogramDie.addAttribute(DW_AT_name, DW_FORM_strp, "main");
SubprogramDie.addAttribute(DW_AT_low_pc, DW_FORM_addr, 0x1000U);
SubprogramDie.addAttribute(DW_AT_high_pc, DW_FORM_addr, 0x2000U);

dwarfgen::DIE IntDie = CUDie.addChild(DW_TAG_base_type);
IntDie.addAttribute(DW_AT_name, DW_FORM_strp, "int");
IntDie.addAttribute(DW_AT_encoding, DW_FORM_data1, DW_ATE_signed);
IntDie.addAttribute(DW_AT_byte_size, DW_FORM_data1, 4);

dwarfgen::DIE ArgcDie = SubprogramDie.addChild(DW_TAG_formal_parameter);
ArgcDie.addAttribute(DW_AT_name, DW_FORM_strp, "argc");
// ArgcDie.addAttribute(DW_AT_type, DW_FORM_ref4, IntDie);
ArgcDie.addAttribute(DW_AT_type, DW_FORM_ref_addr, IntDie);

StringRef FileBytes = DG.generate();
MemoryBufferRef FileBuffer(FileBytes, "dwarf");
auto Obj = object::ObjectFile::createObjectFile(FileBuffer);
EXPECT_TRUE((bool)Obj);
DWARFContextInMemory DwarfContext(*Obj.get());
This code is backed by the AsmPrinter code that emits DWARF for the actual compiler.

While adding unit tests it was discovered that DIEValue that used DIEEntry as their values had bugs where DW_FORM_ref1, DW_FORM_ref2, DW_FORM_ref8, and DW_FORM_ref_udata forms were not supported. These are all now supported. Added support for DW_FORM_string so we can emit inlined C strings.

Centralized the code to unique abbreviations into a new DIEAbbrevSet class and made both the dwarfgen::Generator and the llvm::DwarfFile classes use the new class.

Fixed comments in the llvm::DIE class so that the Offset is known to be the compile/type unit offset.

DIEInteger now supports more DW_FORM values.

There are also unit tests that cover:

Encoding and decoding all form types and values
Encoding and decoding all reference types (DW_FORM_ref1, DW_FORM_ref2, DW_FORM_ref4, DW_FORM_ref8, DW_FORM_ref_udata, DW_FORM_ref_addr) including cross compile unit references with that go forward one compile unit and backward on compile unit.

Differential Revision: https://reviews.llvm.org/D27326

llvm-svn: 289010
2016-12-08 01:03:48 +00:00
Matthias Braun e2d2ead661 TargetPassConfig: Rename DisablePostRA -> DisablePostRASched; NFC
llvm-svn: 289003
2016-12-08 00:16:08 +00:00
Matthias Braun 0c989a893b LivePhysReg: Use reference instead of pointer in init(); NFC
llvm-svn: 289002
2016-12-08 00:15:51 +00:00
Quentin Colombet ae3168da3f [InlineSpiller] Don't call TargetInstrInfo::foldMemoryOperand with an empty list.
Since r287792 if we try to do that we will hit an assert.

llvm-svn: 289001
2016-12-08 00:06:51 +00:00
Tim Northover c53606ef02 GlobalISel: use correct builder for ConstantExprs.
ConstantExpr instances were emitting code into the current block rather than
the entry block. This meant they didn't necessarily dominate all uses, which is
clearly wrong.

llvm-svn: 288985
2016-12-07 21:29:15 +00:00
Tim Northover 50db7f416c GlobalISel: store the current MachineFunction as direct state. NFC.
Having to ask the MIRBuilder for the current function is a little awkward, and
I'm intending to improve how that's threaded through anyway.

llvm-svn: 288983
2016-12-07 21:17:47 +00:00
Tim Northover 05cc4859ad GlobalISel: simplify MachineIRBuilder interface.
MachineIRBuilder had weird before/after and beginning/end flags for the insert
point. Unfortunately the non-default means that instructions will be inserted
in reverse order which is almost never what anyone wants.

Really, I think we just want (like IRBuilder has) the ability to insert at any
C++ iterator-style point (i.e. before any instruction or before MBB.end()). So
this fixes MIRBuilders to behave like IRBuilders in this respect.

llvm-svn: 288980
2016-12-07 21:05:38 +00:00
Simon Pilgrim ba05d41095 [SelectionDAG] Add knownbits support for vector demandedelts in SMAX/SMIN/UMAX/UMIN opcodes
llvm-svn: 288926
2016-12-07 17:54:00 +00:00
Simon Pilgrim 967325b373 [SelectionDAG] Add knownbits support for EXTRACT_VECTOR_ELT opcodes
llvm-svn: 288916
2016-12-07 16:28:21 +00:00
Simon Pilgrim ff79f31328 [SelectionDAG] Removed old knownbits TODO comment. NFCI.
EXTRACT_VECTOR_ELT does support demanded elts if the element index is known and in range.

llvm-svn: 288913
2016-12-07 15:31:12 +00:00
Eli Friedman 0a76e3241f [CodeGen] Fix result type for SMULO/UMULO legalization
On some platforms (like MSP430) the second element of the result
structure for SMULO/UMULO may have a shorter type than the one
returned by SetCC. We need to truncate it to the right type, or
else some incorrect code may be generated later on.

This fixes issue https://github.com/rust-lang/rust/issues/37829

Patch by Vadzim Dambrouski!

Differential Revision: https://reviews.llvm.org/D27154

llvm-svn: 288857
2016-12-06 22:49:36 +00:00
Tim Northover 14ceb45fb4 GlobalISel: correctly handle small args via memory.
We were rounding size in bits down rather than up, leading to 0-sized slots for
i1 (assert!) and bugs for other types not byte-aligned.

llvm-svn: 288848
2016-12-06 21:02:19 +00:00
Simon Pilgrim dd6ca639d5 [DAGCombine] Add (sext_in_reg (zext x)) -> (sext x) combine
Handle the case where a sign extension has ended up being split into separate stages (typically to get around vector legal ops) and a zext + sext_in_reg gets inserted.

Differential Revision: https://reviews.llvm.org/D27461

llvm-svn: 288842
2016-12-06 19:09:37 +00:00
Tim Northover 0a683e7bfd GlobalISel: fall back gracefully when we hit unhandled legalizer default.
llvm-svn: 288840
2016-12-06 19:02:15 +00:00
Simon Pilgrim 1577b39f51 [SelectionDAG] We can ignore knownbits from an undef shuffle vector index if we don't actually demand that element
llvm-svn: 288839
2016-12-06 18:58:25 +00:00
Tim Northover c1a23854f3 GlobalISel: handle G_SEQUENCE fallbacks gracefully.
There were two problems:
  + AArch64 was reusing random data from its binary op tables, which is
    complete nonsense for G_SEQUENCE.
  + Even when AArch64 gave up and said it couldn't handle G_SEQUENCE,
    the generic code asserted.

llvm-svn: 288836
2016-12-06 18:38:38 +00:00
Tim Northover f50f2f3d32 GlobalISel: allow G_SELECT instructions for pointers.
llvm-svn: 288835
2016-12-06 18:38:34 +00:00
Tim Northover 405e25cd6a GlobalISel: stop the legalizer from trying to handle oddly-sized types.
It'll almost immediately fail because it always tries to half/double the size
until it finds a legal one. Unfortunately, this triggers an assertion
preventing the DAG fallback from being possible.

llvm-svn: 288834
2016-12-06 18:38:29 +00:00
Simon Pilgrim 29c17f3f58 Avoid repeated calls to Op.getOpcode(). NFCI.
llvm-svn: 288814
2016-12-06 14:50:09 +00:00
Sam McCall 03435f57aa Add missing parens in assert.
Summary: Add missing parens in assert, which warn in GCC.

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D27448

llvm-svn: 288792
2016-12-06 10:14:36 +00:00
Tim Northover 800638fd67 GlobalISel: avoid looking too closely at PHIs when we bail.
The function used to finish off PHIs by adding the relevant basic blocks can
fail if we're aborting and still don't actually have the needed
MachineBasicBlocks. So avoid trying in that case.

llvm-svn: 288727
2016-12-05 23:10:19 +00:00
Tim Northover b566848d68 GlobalISel: place constants correctly in the entry block.
When the entry block was empty after arg lowering, we were always placing
constants at the end. This is probably hamrless while translating the same
block, but horribly wrong once its terminator has been translated. So switch to
inserting at the beginning.

llvm-svn: 288720
2016-12-05 22:40:13 +00:00
Tim Northover c0bd197c6b GlobalISel: handle pointer arguments that get assigned to the stack.
llvm-svn: 288717
2016-12-05 22:20:32 +00:00
Tim Northover cc35f90492 GlobalISel: translate constants larger than 64 bits.
llvm-svn: 288713
2016-12-05 21:54:17 +00:00
Tim Northover 9267ac5d47 GlobalISel: make G_CONSTANT take a ConstantInt rather than int64_t.
This makes it more similar to the floating-point constant, and also allows for
larger constants to be translated later. There's no real functional change in
this patch though, just syntax updates.

llvm-svn: 288712
2016-12-05 21:47:07 +00:00
Tim Northover 6ad7b9f837 GlobalISel: improve translation fallback for constants.
Returning 0 (NoReg) from getOrCreateVReg leads to unexpected situations later
in the translation. It's better to return a valid (if undefined) register and
let the rest of the instruction carry on as planned.

llvm-svn: 288709
2016-12-05 21:40:33 +00:00
Adrian Prantl 941fa7588b [DIExpression] Introduce a dedicated DW_OP_LLVM_fragment operation
so we can stop using DW_OP_bit_piece with the wrong semantics.

The entire back story can be found here:
http://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20161114/405934.html

The gist is that in LLVM we've been misinterpreting DW_OP_bit_piece's
offset field to mean the offset into the source variable rather than
the offset into the location at the top the DWARF expression stack. In
order to be able to fix this in a subsequent patch, this patch
introduces a dedicated DW_OP_LLVM_fragment operation with the
semantics that we used to apply to DW_OP_bit_piece, which is what we
actually need while inside of LLVM. This patch is complete with a
bitcode upgrade for expressions using the old format. It does not yet
fix the DWARF backend to use DW_OP_bit_piece correctly.

Implementation note: We discussed several options for implementing
this, including reserving a dedicated field in DIExpression for the
fragment size and offset, but using an custom operator at the end of
the expression works just fine and is more efficient because we then
only pay for it when we need it.

Differential Revision: https://reviews.llvm.org/D27361
rdar://problem/29335809

llvm-svn: 288683
2016-12-05 18:04:47 +00:00
Sanjay Patel 1f158d6955 [TargetLowering] add special-case for demanded bits analysis of 'not'
We treat bitwise 'not' as a special operation and try not to reduce its all-ones mask. 
Presumably, this is because a 'not' may be cheaper than a generic 'xor' or it may get
folded into another logic op if the target has those. However, if we can remove a logic
instruction by changing the xor's constant mask value, that should always be a win.

Note that the IR version of SimplifyDemandedBits() does not treat 'not' as a special-case
currently (although that's marked with a FIXME). So if you run this IR through -instcombine,
you should get the same end result. I'm hoping to add a different backend transform that 
will expose this problem though, so I need to solve this first.

Differential Revision: https://reviews.llvm.org/D27356

llvm-svn: 288676
2016-12-05 15:58:21 +00:00
Diana Picus f11f042ecb [GlobalISel] Extract handleAssignments out of AArch64CallLowering
This function seems target-independent so far: all the target-specific behaviour
is isolated in the CCAssignFn and the ValueHandler (which we're also extracting
into the generic CallLowering).

The intention is to use this in the ARM backend.

Differential Revision: https://reviews.llvm.org/D27045

llvm-svn: 288658
2016-12-05 10:40:33 +00:00
Matt Arsenault 92fede361f DAG: Fold out out of bounds insert_vector_elt
getNode already prevents formation of out of bounds constant
extract_vector_elts. Do the same for insert_vector_elt.

llvm-svn: 288603
2016-12-03 23:03:26 +00:00
Nicolai Haehnle 33ca182c91 [DAGCombiner] do not fold (fmul (fadd X, 1), Y) -> (fmad X, Y, Y) by default
Summary:
When X = 0 and Y = inf, the original code produces inf, but the transformed
code produces nan. So this transform (and its relatives) should only be
used when the no-infs-fp-math flag is explicitly enabled.

Also disable the transform using fmad (intermediate rounding) when unsafe-math
is not enabled, since it can reduce the precision of the result; consider this
example with binary floating point numbers with two bits of mantissa:

  x = 1.01
  y = 111

  x * (y + 1) = 1.01 * 1000 = 1010 (this is the exact result; no rounding occurs at any step)

  x * y + x = 1000.11 + 1.01 =r 1000 + 1.01 = 1001.01 =r 1000 (with rounding towards zero)

The example relies on rounding towards zero at least in the second step.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=98578

Reviewers: RKSimon, tstellarAMD, spatel, arsenm

Subscribers: wdng, llvm-commits

Differential Revision: https://reviews.llvm.org/D26602

llvm-svn: 288506
2016-12-02 16:06:18 +00:00
Peter Collingbourne 25a40759c1 Fix GlobalISel build.
llvm-svn: 288460
2016-12-02 02:55:30 +00:00
Peter Collingbourne ab85225be4 IR: Change the gep_type_iterator API to avoid always exposing the "current" type.
Instead, expose whether the current type is an array or a struct, if an array
what the upper bound is, and if a struct the struct type itself. This is
in preparation for a later change which will make PointerType derive from
Type rather than SequentialType.

Differential Revision: https://reviews.llvm.org/D26594

llvm-svn: 288458
2016-12-02 02:24:42 +00:00
Paul Robinson dad4907bc1 [DWARF] Put linkage-name on abstract origin even when there's a declaration.
In r266692, we made it possible to emit linkage names for just inlined
functions, putting the attribute on the abstract origin. Make sure we
don't think the linkage-name was already emitted on a declaration.

Differential Revision: http://reviews.llvm.org/D27320

llvm-svn: 288450
2016-12-02 01:55:17 +00:00
Wolfgang Pieb 42f92a7225 When instructions are hoisted out of loops by MachineLICM, remove their debug loc.
This prevents erratic stepping behavior as well as incorrect source attribution
for sample profiling.

Reviewers: dblakie

Subscribers: llvm-commit

Differential Revision: https://reviews.llvm.org/D27290

llvm-svn: 288442
2016-12-02 00:37:57 +00:00
Justin Bogner 35c5e58f8c SDAG: Avoid a large, usually empty SmallVector in a recursive function
This SmallVector is using up 128 bytes on the stack every time despite
almost always being empty[1], and since this function can recurse quite
deeply that adds up to a lot of overhead. We've seen this run afoul of
ulimits in some cases with ASAN on.

Replacing the SmallVector with a std::vector trades an occasional heap
allocation for vastly less stack usage.

[1]: I gathered some stats on an internal test suite and the vector
was non-empty in only 45,000 of 10,000,000 calls to this function.

llvm-svn: 288441
2016-12-02 00:11:01 +00:00
Dan Gohman 734c59d501 [MC] Refactor emitELFSize to make usage more consistent. NFC.
Move the cast<MCSymbolELF> inside emitELFSize, so that: 
 - it's done in one place instead of at each call
 - it's more consistent with similar functions like EmitCOFFSafeSEH
 - ambiguity between cast<> and dyn_cast<> is avoided (which also
   eliminates an unnecessary dyn_cast call)

This also makes it easier to experiment with using ".size" directives on
non-ELF targets.

llvm-svn: 288437
2016-12-01 23:39:08 +00:00
Matthias Braun 709a4cc238 RegisterCoalscer: Only coalesce complete reserved registers.
The coalescer eliminates copies from reserved registers of the form:
   %vregX = COPY %rY
in the case where %rY is a reserved register. However this turns out to
be invalid if only some of the subregisters are reserved (see also
https://reviews.llvm.org/D26648).

Differential Revision: https://reviews.llvm.org/D26687

llvm-svn: 288428
2016-12-01 22:39:51 +00:00
David Blaikie e40caaee99 [debug info] Minor cleanup from D27170/r288399
llvm-svn: 288421
2016-12-01 21:59:09 +00:00
Matthias Braun d0ee66c2e9 Move most EH from MachineModuleInfo to MachineFunction
Recommitting r288293 with some extra fixes for GlobalISel code.

Most of the exception handling members in MachineModuleInfo is actually
per function data (talks about the "current function") so it is better
to keep it at the function instead of the module.

This is a necessary step to have machine module passes work properly.

Also:
- Rename TidyLandingPads() to tidyLandingPads()
- Use doxygen member groups instead of "//===- EH ---"... so it is clear
  where a group ends.
- I had to add an ugly const_cast at two places in the AsmPrinter
  because the available MachineFunction pointers are const, but the code
  wants to call tidyLandingPads() in between
  (markFunctionEnd()/endFunction()).

Differential Revision: https://reviews.llvm.org/D27227

llvm-svn: 288405
2016-12-01 19:32:15 +00:00
Benjamin Kramer 6a8704c1c0 Fix unused variable warning in Release builds. NFC.
llvm-svn: 288401
2016-12-01 19:10:10 +00:00
Greg Clayton 35630c3357 This change removes the dependency on DwarfDebug that was used for DW_FORM_ref_addr by making a new DIEUnit class in DIE.cpp.
The DIEUnit class represents a compile or type unit and it owns the unit DIE as an instance variable. This allows anyone with a DIE, to get the unit DIE, and then get back to its DIEUnit without adding any new ivars to the DIE class. Why was this needed? The DIE class has an Offset that is always the CU relative DIE offset, not the "offset in debug info section" as was commented in the header file (the comment has been corrected). This is great for performance because most DIE references are compile unit relative and this means most code that accessed the DIE's offset didn't need to make it into a compile unit relative offset because it already was. When we needed to emit a DW_FORM_ref_addr though, we needed to find the absolute offset of the DIE by finding the DIE's compile/type unit. This class did have the absolute debug info/type offset and could be added to the CU relative offset to compute the absolute offset. With this change we can easily get back to a DIE's DIEUnit which will have this needed offset. Prior to this is required having a DwarfDebug and required calling:

DwarfCompileUnit *DwarfDebug::lookupUnit(const DIE *CU) const;
Now we can use the DIEUnit class to do so without needing DwarfDebug. All clients now use DIEUnit objects (the DwarfDebug stack and the DwarfLinker). A follow on patch for the DWARF generator will also take advantage of this.

Differential Revision: https://reviews.llvm.org/D27170

llvm-svn: 288399
2016-12-01 18:56:29 +00:00
Nicolai Haehnle da7e4017c6 [SelectionDAG] Rename and clarify visitFMULForFMADCombine (NFC)
Summary: Suggested by @spatel in D26602.

Reviewers: spatel, hfinkel

Subscribers: spatel, llvm-commits

Differential Revision: https://reviews.llvm.org/D27260

llvm-svn: 288336
2016-12-01 14:04:13 +00:00
Eric Christopher e70b7c3dfb Temporarily Revert "Move most EH from MachineModuleInfo to MachineFunction"
This apprears to have broken the global isel bot:
http://lab.llvm.org:8080/green/job/clang-stage1-cmake-RA-globalisel_build/5174/console

This reverts commit r288293.

llvm-svn: 288322
2016-12-01 07:50:12 +00:00
Kostya Serebryany b66cb88c2e revert r288283 as it causes debug info (line numbers) to be lost in instrumented code. also revert r288299 which was a workaround for the problem.
llvm-svn: 288300
2016-12-01 02:06:56 +00:00
Matthias Braun ed14cb0604 Move most EH from MachineModuleInfo to MachineFunction
Most of the exception handling members in MachineModuleInfo is actually
per function data (talks about the "current function") so it is better
to keep it at the function instead of the module.

This is a necessary step to have machine module passes work properly.

Also:
- Rename TidyLandingPads() to tidyLandingPads()
- Use doxygen member groups instead of "//===- EH ---"... so it is clear
  where a group ends.
- I had to add an ugly const_cast at two places in the AsmPrinter
  because the available MachineFunction pointers are const, but the code
  wants to call tidyLandingPads() in between
  (markFunctionEnd()/endFunction()).

Differential Revision: https://reviews.llvm.org/D27227

llvm-svn: 288293
2016-11-30 23:49:01 +00:00
Matthias Braun ef331eff5a Move VariableDbgInfo from MachineModuleInfo to MachineFunction
VariableDbgInfo is per function data, so it makes sense to have it with
the function instead of the module.

This is a necessary step to have machine module passes work properly.

Differential Revision: https://reviews.llvm.org/D27186

llvm-svn: 288292
2016-11-30 23:48:50 +00:00
Matthias Braun f23ef437cc Move FrameInstructions from MachineModuleInfo to MachineFunction
This is per function data so it is better kept at the function instead
of the module.

This is a necessary step to have machine module passes work properly.

Differential Revision: https://reviews.llvm.org/D27185

llvm-svn: 288291
2016-11-30 23:48:42 +00:00
Paul Robinson 37a13ddb4b Recommit r288212: Emit 'no line' information for interesting 'orphan' instructions.
The LLDB tests are now ready for this patch.

DWARF specifies that "line 0" really means "no appropriate source
location" in the line table.  Use this for branch targets and some
other cases that have no specified source location, to prevent
inheriting unfortunate line numbers from physically preceding
instructions (which might be from completely unrelated source).

Differential Revision: http://reviews.llvm.org/D24180

llvm-svn: 288283
2016-11-30 22:49:55 +00:00
Matthias Braun c52fe2961c Clarify rules for reserved regs, fix aarch64 ones.
No test case necessary as the problematic condition is checked with the
newly introduced assertAllSuperRegsMarked() function.

Differential Revision: https://reviews.llvm.org/D26648

llvm-svn: 288277
2016-11-30 22:17:10 +00:00
Nicolai Haehnle 73a9a27b5a [SelectionDAG] Refactor TargetLowering::expandMUL (NFC)
Summary: Further preparation for the expansion of MUL_LOHI added in D24956.

Reviewers: efriedma, RKSimon

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D27064

llvm-svn: 288248
2016-11-30 16:26:33 +00:00
Paul Robinson 957ba405e8 Revert r288212 due to lldb failure.
llvm-svn: 288216
2016-11-29 23:20:35 +00:00
Paul Robinson 96de8c778b Emit 'no line' information for interesting 'orphan' instructions.
DWARF specifies that "line 0" really means "no appropriate source
location" in the line table.  Use this for branch targets and some
other cases that have no specified source location, to prevent
inheriting unfortunate line numbers from physically preceding
instructions (which might be from completely unrelated source).

Differential Revision: http://reviews.llvm.org/D24180

llvm-svn: 288212
2016-11-29 22:41:16 +00:00
Geoff Berry 4d66cea347 [LiveRangeEdit] Handle instructions with no defs correctly.
Summary:
The code in LiveRangeEdit::eliminateDeadDef() that computes isOrigDef
doesn't handle instructions in which operand 0 is not a def (e.g. KILL)
correctly.  Add a check that operand 0 is a def before doing the rest of
the isOrigDef computation.

Reviewers: qcolombet, MatzeB, wmi

Subscribers: mcrosier, llvm-commits

Differential Revision: https://reviews.llvm.org/D27174

llvm-svn: 288189
2016-11-29 19:31:35 +00:00
Warren Ristow d9777c1dbb Test commit. Comment changes. NFC.
llvm-svn: 288100
2016-11-29 02:37:13 +00:00
Reid Kleckner c68a6c4ca9 Recognize ${:uid} escapes in intel syntax inline asm
It looks like this logic was duplicated long ago and the GCC side of
things has grown additional functionality. We need ${:uid} at least to
generate unique MS inline asm labels (PR23715), so expose these.

llvm-svn: 288092
2016-11-29 00:29:27 +00:00
Sanjay Patel 2bd32b05fb [DAG] clean up foldSelectCCToShiftAnd(); NFCI
llvm-svn: 288088
2016-11-28 23:05:55 +00:00
Sanjay Patel 1cf9aff659 [DAG] add helper function for selectcc --> and+shift transforms; NFC
llvm-svn: 288073
2016-11-28 21:47:41 +00:00
David Blaikie ce3c8ef26e [DebugInfo] Add support for DW_AT_main_subprogram on subprograms
Patch by Tom Tromey! (for use with Rust)

llvm-svn: 288068
2016-11-28 21:32:19 +00:00
Matthias Braun 115efcd3d1 MachineScheduler: Export function to construct "default" scheduler.
This makes the createGenericSchedLive() function that constructs the
default scheduler available for the public API. This should help when
you want to get a scheduler and the default list of DAG mutations.

This also shrinks the list of default DAG mutations:
{Load|Store}ClusterDAGMutation and MacroFusionDAGMutation are no longer
added by default. Targets can easily add them if they need them. It also
makes it easier for targets to add alternative/custom macrofusion or
clustering mutations while staying with the default
createGenericSchedLive(). It also saves the callback back and forth in
TargetInstrInfo::enableClusterLoads()/enableClusterStores().

Differential Revision: https://reviews.llvm.org/D26986

llvm-svn: 288057
2016-11-28 20:11:54 +00:00
Joerg Sonnenberger caaa82d90d Revert r287553: [CodeGenPrep] Skip merging empty case blocks
It results in assertions in lib/Analysis/BlockFrequencyInfoImpl.cpp line
670 ("Expected irreducible CFG").

llvm-svn: 288052
2016-11-28 18:56:54 +00:00
Nirav Dave a413361798 Revert "[DAG] Improve loads-from-store forwarding to handle TokenFactor"
This reverts commit r287773 which caused issues with ppc64le builds.

llvm-svn: 288035
2016-11-28 14:30:29 +00:00
Simon Pilgrim c5fb167df0 Use SDValue helpers instead of explicitly going via SDValue::getNode(). NFCI
llvm-svn: 287941
2016-11-25 17:25:21 +00:00
Craig Topper 8c4cdf06db [DAGCombine] Teach DAG combine that if both inputs of a vselect are the same, then the condition doesn't matter and the vselect can be removed.
Selects with scalar condition already handle this correctly.

llvm-svn: 287904
2016-11-24 21:48:52 +00:00
Serge Rogatch a331133e6d Test commit access.
llvm-svn: 287898
2016-11-24 18:51:47 +00:00
Matt Arsenault 94b32ffe8e TRI: Add hook to pass scavenger during frame elimination
The scavenger was not passed if requiresFrameIndexScavenging was
enabled. I need to be able to test for the availability of an
unallocatable register here, so I can't create a virtual register for
it.

It might be better to just always use the scavenger and stop
creating virtual registers.

llvm-svn: 287843
2016-11-24 00:26:47 +00:00
Greg Clayton e65439797a Rely on a single DWARF version instead of having two copies
This patch makes AsmPrinter less reliant on DwarfDebug by relying on the DWARF version in the AsmPrinter's MCStreamer's MCContext. This allows us to remove the redundant DWARF version from DwarfDebug. It also lets us change code that used to access the AsmPrinter's DwarfDebug just to get to the DWARF version by changing the DWARF version accessor on AsmPrinter so that it grabs the version from its MCStreamer's MCContext.

Differential Revision: https://reviews.llvm.org/D27032

llvm-svn: 287839
2016-11-23 23:30:37 +00:00
Nicolai Haehnle 934470f536 [SelectionDAG] Early-out in TargetLowering::expandMUL (NFC)
Summary: Reduce indentation level; preparation for D24956.

Reviewers: efriedma

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D27063

llvm-svn: 287831
2016-11-23 22:14:20 +00:00
Michael Kuperstein 47eb85a003 [X86] Allow folding of stack reloads when loading a subreg of the spilled reg
We did not support subregs in InlineSpiller:foldMemoryOperand() because targets
may not deal with them correctly.

This adds a target hook to let the spiller know that a target can handle
subregs, and actually enables it for x86 for the case of stack slot reloads.
This fixes PR30832.

Differential Revision: https://reviews.llvm.org/D26521

llvm-svn: 287792
2016-11-23 18:33:49 +00:00
Nirav Dave cf34556330 [DAG] Improve loads-from-store forwarding to handle TokenFactor
Forward store values to matching loads down through token
factors. Factored from D14834.

Reviewers: jyknight, hfinkel

Subscribers: hfinkel, nemanjai, llvm-commits

Differential Revision: https://reviews.llvm.org/D26080

llvm-svn: 287773
2016-11-23 16:48:35 +00:00
John Brawn 150addb45c [DAGCombiner] Fix infinite loop in vector mul/shl combining
We have the following DAGCombiner transformations:
 (mul (shl X, c1), c2) -> (mul X, c2 << c1)
 (mul (shl X, C), Y) -> (shl (mul X, Y), C)
 (shl (mul x, c1), c2) -> (mul x, c1 << c2)
Usually the constant shift is optimised by SelectionDAG::getNode when it is
constructed, by SelectionDAG::FoldConstantArithmetic, but when we're dealing
with vectors and one of those vector constants contains an undef element
FoldConstantArithmetic does not fold and we enter an infinite loop.

Fix this by making FoldConstantArithmetic use getNode to decide how to fold each
vector element, the same as FoldConstantVectorArithmetic does, and rather than
adding the constant shift to the work list instead only apply the transformation
if it's already been folded into a constant, as if it's not we're going to loop
endlessly. Additionally add missing NoOpaques to one of those transformations,
which I noticed when writing the tests for this.

Differential Revision: https://reviews.llvm.org/D26605

llvm-svn: 287766
2016-11-23 16:05:51 +00:00
Elena Demikhovsky 09375d98b8 Type legalization for compressstore and expandload intrinsics.
Implemented widening (v2f32) and splitting (v16f64).
On splitting, I use "popcnt" to calculate memory increment. 
More type legalization work will come in the next patches.

llvm-svn: 287761
2016-11-23 13:58:24 +00:00
Matthias Braun 7f423442d1 TargetSubtargetInfo: Move implementation to lib/CodeGen; NFC
TargetSubtargetInfo is filled with CodeGen specific interfaces nowadays
(getInstrInfo(), getFrameLowering(), getSelectionDAGInfo()) most of the
tuning flags like enablePostRAScheduler(), getAntiDepBreakMode(),
enableRALocalReassignment(), ... also do not seem to be universal enough
to make sense outside of CodeGen.

Differential Revision: https://reviews.llvm.org/D26948

llvm-svn: 287708
2016-11-22 22:09:03 +00:00
Paul Robinson f428c9b298 Restructure DwarfDebug::beginInstruction(). [NFC]
Will help a pending patch.

Differential Revision: http://reviews.llvm.org/D26982

llvm-svn: 287686
2016-11-22 19:46:51 +00:00
Tim Northover b64fb453ea CodeGen: simplify TargetMachine::getSymbol interface. NFC.
No-one actually had a mangler handy when calling this function, and
getSymbol itself went most of the way towards getting its own mangler
(with a local TLOF variable) so forcing all callers to supply one was
just extra complication.

llvm-svn: 287645
2016-11-22 16:17:20 +00:00
Simon Pilgrim 72e43570b7 [SelectionDAG] ComputeNumSignBits of TRUNCATE operations
Add basic ComputeNumSignBits support for TRUNCATE ops for cases where the source's number of sign bits overlaps with the truncated size.

Improves X86 SIGN_EXTEND_IN_REG vector cases which were needlessly sign extending boolean vector results.

Differential Revision: https://reviews.llvm.org/D26851

llvm-svn: 287635
2016-11-22 11:29:19 +00:00
Matt Arsenault b30d2aca58 DAG: Ignore call site attributes when emitting target intrinsic
A target intrinsic may be defined as possibly reading memory,
but the call site may have additional knowledge that it doesn't read
memory. The intrinsic lowering will expect the pessimistic
assumption of the intrinsic definition, so the chain should
still be used.

llvm-svn: 287593
2016-11-21 22:56:42 +00:00
Justin Lebar 3e50a5be8f [CodeGenPrepare] Don't sink non-cheap addrspacecasts.
Summary:
Previously, CGP would unconditionally sink addrspacecast instructions,
even going so far as to sink them into a loop.

Now we check that the cast is "cheap", as defined by TLI.

We introduce a new "is-cheap" function to TLI rather than using
isNopAddrSpaceCast because some GPU platforms want the ability to ask
for non-nop casts to be sunk.

Reviewers: arsenm, tra

Subscribers: jholewinski, wdng, llvm-commits

Differential Revision: https://reviews.llvm.org/D26923

llvm-svn: 287591
2016-11-21 22:49:15 +00:00
Justin Lebar 838c7f5a85 [CodeGenPrepare] Rewrite a loop in terms of llvm::none_of. NFC.
Reviewers: arsenm

Subscribers: wdng, llvm-commits

Differential Revision: https://reviews.llvm.org/D26924

llvm-svn: 287590
2016-11-21 22:49:11 +00:00
Krzysztof Parzyszek 73c8a9bc2f Check proper live range in extendPHIRanges
The function extendPHIRanges checks the main range of the original live
interval, even when dealing with a subrange. This could also lead to an
assert when the subrange is not live at the extension point, but the
main range is. To avoid this, check the corresponding subrange of the
original live range, instead of always checking the main range.

Review (as a part of a bigger set of changes):
https://reviews.llvm.org/D26359

llvm-svn: 287571
2016-11-21 20:24:12 +00:00
Shoaib Meenai 106e05a0e8 [AsmPrinter] Enable codeview for windows-itanium
Enable codeview emission for windows-itanium targets. Co-opt an existing
test (which is derived from a C source file and should therefore be
identical across the Itanium and MS ABIs).

Differential Revision: https://reviews.llvm.org/D26693

llvm-svn: 287567
2016-11-21 20:13:32 +00:00
Simon Pilgrim 5662074ba3 [VectorLegalizer] Remove EVT::getSizeInBits code duplications. NFCI.
We were calling SVT.getSizeInBits() several times in a row - just call it once and reuse the result.

llvm-svn: 287556
2016-11-21 18:24:44 +00:00
Jun Bum Lim 82f55c5446 [CodeGenPrep] Skip merging empty case blocks
Summary: Merging an empty case block into the header block of switch could cause
ISel to add COPY instructions in the header of switch, instead of the case
block, if the case block is used as an incoming block of a PHI. This could
potentially increase dynamic instructions, especially when the switch is in a
loop. I added a test case which was reduced from the benchmark I was targetting.

Reviewers: t.p.northover, mcrosier, manmanren, wmi, davidxl

Subscribers: qcolombet, danielcdh, hfinkel, mcrosier, llvm-commits

Differential Revision: https://reviews.llvm.org/D22696

llvm-svn: 287553
2016-11-21 16:47:28 +00:00
Simon Pilgrim 49d7eda968 [SelectionDAG] Add ComputeNumSignBits support for CONCAT_VECTORS opcode
llvm-svn: 287541
2016-11-21 14:36:19 +00:00
Simon Pilgrim f2fbf43704 Fix comment typos. NFC.
Identified by Pedro Giffuni in PR27636.

llvm-svn: 287490
2016-11-20 13:47:59 +00:00
Simon Pilgrim 7a6b6d5656 Fix spelling mistakes in SelectionDAG comments. NFC.
Identified by Pedro Giffuni in PR27636.

llvm-svn: 287487
2016-11-20 13:14:57 +00:00
Simon Pilgrim e40900dddd [SelectionDAG] Add knowbits support for CONCAT_VECTOR opcode
llvm-svn: 287387
2016-11-18 22:21:22 +00:00
Matthias Braun 9f15a79e5d Timer: Track name and description.
The previously used "names" are rather descriptions (they use multiple
words and contain spaces), use short programming language identifier
like strings for the "names" which should be used when exporting to
machine parseable formats.

Also removed a unused TimerGroup from Hexxagon.

Differential Revision: https://reviews.llvm.org/D25583

llvm-svn: 287369
2016-11-18 19:43:18 +00:00
Geoff Berry b51774ac8c [MIRPrinter] Print raw branch probabilities as expected by MIRParser
Fixes PR28751.

Reviewers: MatzeB, qcolombet

Subscribers: mcrosier, llvm-commits

Differential Revision: https://reviews.llvm.org/D26775

llvm-svn: 287368
2016-11-18 19:37:24 +00:00
Tom Stellard df613198c0 GlobalISel: Fix unconditional fallback with global isel abort is disabled
Reviewers: t.p.northover, ab, qcolombet

Subscribers: mehdi_amini, vkalintiris, wdng, dberris, llvm-commits, rovka

Differential Revision: https://reviews.llvm.org/D26765

llvm-svn: 287344
2016-11-18 14:14:35 +00:00
Matthias Braun 637488dbf8 MachineOperand: Add dump() method
llvm-svn: 287302
2016-11-18 02:40:40 +00:00
Simon Pilgrim c4d733cd6a Fix spelling in comment. NFC.
llvm-svn: 287222
2016-11-17 12:03:05 +00:00
Sanjoy Das 43ccb38bb5 Delete dead code and add asserts instead; NFC
llvm-svn: 287214
2016-11-17 07:29:43 +00:00
Sanjoy Das 4a8fe09040 [ImplicitNullCheck] Fix an edge case where we were hoisting incorrectly
ImplicitNullCheck keeps track of one instruction that the memory
operation depends on that it also hoists with the memory operation.
When hoisting this dependency, it would sometimes clobber a live-in
value to the basic block we were hoisting the two things out of.  Fix
this by explicitly looking for such dependencies.

I also noticed two redundant checks on `MO.isDef()` in IsMIOperandSafe.
They're redundant since register MachineOperands are either Defs or Uses
-- there is no third kind.  I'll change the checks to asserts in a later
commit.

llvm-svn: 287213
2016-11-17 07:29:40 +00:00
Dean Michael Berris 3234d3a4bd [XRay] Support AArch64 in LLVM
This patch adds XRay support in LLVM for AArch64 targets.
This patch is one of a series:

Clang: https://reviews.llvm.org/D26415
compiler-rt: https://reviews.llvm.org/D26413

Author: rSerge

Reviewers: rengolin, dberris

Subscribers: amehsan, aemerson, llvm-commits, iid_iunknown

Differential Revision: https://reviews.llvm.org/D26412

llvm-svn: 287209
2016-11-17 05:15:37 +00:00
Chris Bieneman 05c279fc4b [CMake] NFC. Updating CMake dependency specifications
This patch updates a bunch of places where add_dependencies was being explicitly called to add dependencies on intrinsics_gen to instead use the DEPENDS named parameter. This cleanup is needed for a patch I'm working on to add a dependency debugging mode to the build system.

llvm-svn: 287206
2016-11-17 04:36:50 +00:00
Ahmed Bougacha bd6ce9a247 [CodeGen] Pass references, not pointers, to MMI helpers. NFC.
While there, rename them to follow the coding style.

llvm-svn: 287169
2016-11-16 22:25:03 +00:00
Ahmed Bougacha 996961a461 Revert "Get GlobalISel to build on Linux after r286407"
This reverts commit r286962.

We want to avoid depending on SelectionDAG, and AddLandingPadInfo
lives in CodeGen now.

llvm-svn: 287168
2016-11-16 22:24:59 +00:00
Ahmed Bougacha 456dce8a84 [CodeGen] Pull MMI helpers from FunctionLoweringInfo to MMI. NFC.
They're not SelectionDAG- or FunctionLoweringInfo-specific.  They
are, however, specific to building MMI from IR.
We could make them members, but it's nice having MMI be a "simple" data
structure and this logic kept separate.

This also lets us reuse them from GlobalISel.

llvm-svn: 287167
2016-11-16 22:24:56 +00:00
Ahmed Bougacha 2b4c127531 [CodeGen] Cleanup MachineModuleInfo doxygen comments. NFC.
Remove redundant names and only keep header comments.

llvm-svn: 287166
2016-11-16 22:24:53 +00:00
Sanjoy Das df4b162e4d [ImplicitNullChecks] Do not not handle call MachineInstrs
We don't track callee clobbered registers correctly, so avoid hoisting
across calls.

Note: for this bug to trigger we need a `readonly` call target, since we
already have logic to not hoist across potentially storing instructions
either.

llvm-svn: 287159
2016-11-16 21:45:22 +00:00
Rong Xu 66827427e1 Make block placement deterministic
We fail to produce bit-to-bit matching stage2 and stage3 compiler in PGO
bootstrap build. The reason is because LoopBlockSet is of SmallPtrSet type
whose iterating order depends on the pointer value.

This patch fixes this issue by changing to use SmallSetVector.

Differential Revision: http://reviews.llvm.org/D26634

llvm-svn: 287148
2016-11-16 20:50:06 +00:00
Quentin Colombet fb9b0cdcfe [RegAllocGreedy] Record missed hint for late recoloring.
In https://reviews.llvm.org/D25347, Geoff noticed that we still have
useless copy that we can eliminate after register allocation. At the
time the allocation is chosen for those copies, they are not useless
but, because of changes in the surrounding code, later on they might
become useless.
The Greedy allocator already has a mechanism to deal with such cases
with a late recoloring. However, we missed to record the some of the
missed hints.

This commit fixes that.

llvm-svn: 287070
2016-11-16 01:07:12 +00:00
Pawel Bylica c3f6c97f71 Integer legalization: fix MUL expansion
Summary:
This fixes the runtime results produces by the fallback multiplication expansion introduced in r270720.

For tests I created a fuzz tester that compares the results with Boost.Multiprecision.

Reviewers: hfinkel

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D26628

llvm-svn: 286998
2016-11-15 18:29:24 +00:00
Diana Picus 3776e76201 Get GlobalISel to build on Linux after r286407
r286407 has introduced calls to llvm::AddLandingPadInfo, which lives in the
SelectionDAG component. Add it to LLVMBuild to avoid linker failures on Linux.

llvm-svn: 286962
2016-11-15 14:11:11 +00:00
Joerg Sonnenberger 1a7eec68a9 Introduce TLI predicative for base-relative Jump Tables.
For 64bit ABIs it is common practice to use relative Jump Tables with
potentially different relocation bases.  As the logic for the jump table
itself doesn't depend on the relocation base, make it easier for targets
to use the generic logic. Start by dropping the now redundant MIPS logic.

Differential Revision: https://reviews.llvm.org/D26578

llvm-svn: 286951
2016-11-15 12:39:46 +00:00