llvm-6502/include/llvm
Daniel Sanders ea28aafa83 Fix illegal DAG produced by SelectionDAG::getConstant() for v2i64 type
Summary:
When getConstant() is called for an expanded vector type, it is split into
multiple scalar constants which are then combined using appropriate build_vector
and bitcast operations.

In addition to the usual big/little endian differences, the case where the
element-order of the vector does not have the same endianness as the elements
themselves is also accounted for.  For example, for v4i32 on big-endian MIPS,
the byte-order of the vector is <3210,7654,BA98,FEDC>. For little-endian, it is
<0123,4567,89AB,CDEF>.
Handling this case turns out to be a nop since getConstant() returns a splatted
vector (so reversing the element order doesn't change the value)

This fixes a number of cases in MIPS MSA where calling getConstant() during
operation legalization introduces illegal types (e.g. to legalize v2i64 UNDEF
into a v2i64 BUILD_VECTOR of illegal i64 zeros). It should also handle bigger
differences between illegal and legal types such as legalizing v2i64 into v8i16.

lowerMSASplatImm() in the MIPS backend no longer needs to avoid calling
getConstant() so this function has been updated in the same patch.

For the sake of transparency, the steps I've taken since the review are:
* Added 'virtual' to isVectorEltOrderLittleEndian() as requested. This revealed
  that the MIPS tests were falsely passing because a polymorphic function was
  not actually polymorphic in the reviewed patch.
* Fixed the tests that were now failing. This involved deleting the code to
  handle the MIPS MSA element-order (which was previously doing an byte-order
  swap instead of an element-order swap). This left
  isVectorEltOrderLittleEndian() unused and it was deleted.
* Fixed build failures caused by rebasing beyond r194467-r194472. These build
  failures involved the bset, bneg, and bclr instructions added in these commits
  using lowerMSASplatImm() in a way that was no longer valid after this patch.
  Some of these were fixed by calling SelectionDAG::getConstant() instead,
  others were fixed by a new function getBuildVectorSplat() that provided the
  removed functionality of lowerMSASplatImm() in a more sensible way.

Reviewers: bkramer

Reviewed By: bkramer

CC: llvm-commits

Differential Revision: http://llvm-reviews.chandlerc.com/D1973

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@194811 91177308-0d34-0410-b5e6-96231b3b80d8
2013-11-15 12:56:49 +00:00
..
ADT Fix a null pointer dereference when copying a null polymorphic pointer. 2013-11-13 02:48:20 +00:00
Analysis Added BlockFrequencyInfo::view for displaying the block frequency propagation graph via graphviz. 2013-11-14 02:27:46 +00:00
Assembly
Bitcode Add addrspacecast instruction. 2013-11-15 01:34:59 +00:00
CodeGen Fix illegal DAG produced by SelectionDAG::getConstant() for v2i64 type 2013-11-15 12:56:49 +00:00
Config Fix symbol defines in config.h.cmake 2013-11-05 07:27:18 +00:00
DebugInfo DWARF parser: Use ArrayRef to represent form sizes and simplify DWARFDIE::extractFast() interface. No functionality change. 2013-10-28 23:41:49 +00:00
ExecutionEngine Optimizing MCJIT module state tracking 2013-10-24 00:19:14 +00:00
IR Add addrspacecast instruction. 2013-11-15 01:34:59 +00:00
IRReader
LTO Protect user-supplied runtime library functions in LTO 2013-11-12 21:44:01 +00:00
MC Remove AllowQuotesInName and friends from MCAsmInfo. 2013-11-13 14:01:59 +00:00
Object move getSymbolNMTypeChar to the one program that needs it: nm. 2013-11-02 21:16:09 +00:00
Option Option parsing: support case-insensitive option matching. 2013-08-28 20:04:31 +00:00
Support Include raw_ostream.h. 2013-11-15 01:25:34 +00:00
TableGen Speling fixes. 2013-10-22 15:18:03 +00:00
Target Add target hook to prevent folding some bitcasted loads. 2013-11-15 04:42:23 +00:00
Transforms SampleProfileLoader pass. Initial setup. 2013-11-13 12:22:21 +00:00
AutoUpgrade.h Add addrspacecast instruction. 2013-11-15 01:34:59 +00:00
CMakeLists.txt
DebugInfo.h Reformat. 2013-10-15 21:22:12 +00:00
DIBuilder.h fix two typos. 2013-10-21 23:55:19 +00:00
GVMaterializer.h Use error_code in GVMaterializer. 2013-11-05 19:36:34 +00:00
InitializePasses.h SampleProfileLoader pass. Initial setup. 2013-11-13 12:22:21 +00:00
InstVisitor.h Add addrspacecast instruction. 2013-11-15 01:34:59 +00:00
LinkAllIR.h
LinkAllPasses.h Remove the very substantial, largely unmaintained legacy PGO 2013-10-02 15:42:23 +00:00
Linker.h Add a 'deleteModule' method to the Linker class. 2013-10-16 08:59:57 +00:00
Pass.h
PassAnalysisSupport.h
PassManager.h Move the old pass manager infrastructure into a legacy namespace and 2013-11-09 12:26:54 +00:00
PassRegistry.h This patch breaks up Wrap.h so that it does not have to include all of 2013-05-01 20:59:00 +00:00
PassSupport.h