DAGcombine's ability to find reasons to remove truncates when they were not
needed. Consequently, the CellSPU backend would produce correct, but _really
slow and horrible_, code.
Replaced with instruction sequences that do the equivalent truncation in
SPUInstrInfo.td.
- Re-examine how unaligned loads and stores work. Generated unaligned
load code has been tested on the CellSPU hardware; see the i32operations.c
and i64operations.c in CodeGen/CellSPU/useful-harnesses. (While they may be
toy test code, it does prove that some real world code does compile
correctly.)
- Fix truncating stores in bug 3193 (note: unpack_df.ll will still make llc
fault because i64 ult is not yet implemented.)
- Added i64 eq and neq for setcc and select/setcc; started new instruction
information file for them in SPU64InstrInfo.td. Additional i64 operations
should be added to this file and not to SPUInstrInfo.td.
llvm-svn: 61447
for CellSPU modifications:
- SPUInstrInfo.td refactoring: "multiclass" really is _your_ friend.
- Other improvements based on refactoring effort in SPUISelLowering.cpp,
esp. in SPUISelLowering::PerformDAGCombine(), where zero amount shifts and
rotates are now eliminiated, other scalar-to-vector-to-scalar silliness
is also eliminated.
- 64-bit operations are being implemented, _muldi3.c gcc runtime now
compiles and generates the right code. More work still needs to be done.
llvm-svn: 47532
only two addressing mode nodes, SPUaform and SPUindirect (vice the
three previous ones, SPUaform, SPUdform and SPUxform). This improves
code somewhat because we now avoid using reg+reg addressing when
it can be avoided. It also simplifies the address selection logic,
which was the main point for doing this.
Also, for various global variables that would be loaded using SPU's
A-form addressing, prefer D-form offs[reg] addressing, keeping the
base in a register if the variable is used more than once.
llvm-svn: 46483