forked from OSchip/llvm-project
544ab2c50b
on any current target and aren't optimized in DAGCombiner. Instead of using intermediate nodes, expand the operations, choosing between simple loads/stores, target-specific code, and library calls, immediately. Previously, the code to emit optimized code for these operations was only used at initial SelectionDAG construction time; now it is used at all times. This fixes some cases where rep;movs was being used for small copies where simple loads/stores would be better. This also cleans up code that checks for alignments less than 4; let the targets make that decision instead of doing it in target-independent code. This allows x86 to use rep;movs in low-alignment cases. Also, this fixes a bug that resulted in the use of rep;stos for memsets of 0 with non-constant memory size when the alignment was at least 4. It's better to use the library in this case, which can be significantly faster when the size is large. This also preserves more SourceValue information when memory intrinsics are lowered into simple loads/stores. llvm-svn: 49572 |
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|---|---|---|
| .. | ||
| DelaySlotFiller.cpp | ||
| FPMover.cpp | ||
| Makefile | ||
| README.txt | ||
| Sparc.h | ||
| Sparc.td | ||
| SparcAsmPrinter.cpp | ||
| SparcCallingConv.td | ||
| SparcISelDAGToDAG.cpp | ||
| SparcISelLowering.cpp | ||
| SparcISelLowering.h | ||
| SparcInstrFormats.td | ||
| SparcInstrInfo.cpp | ||
| SparcInstrInfo.h | ||
| SparcInstrInfo.td | ||
| SparcRegisterInfo.cpp | ||
| SparcRegisterInfo.h | ||
| SparcRegisterInfo.td | ||
| SparcSubtarget.cpp | ||
| SparcSubtarget.h | ||
| SparcTargetAsmInfo.cpp | ||
| SparcTargetAsmInfo.h | ||
| SparcTargetMachine.cpp | ||
| SparcTargetMachine.h | ||
README.txt
To-do
-----
* Keep the address of the constant pool in a register instead of forming its
address all of the time.
* We can fold small constant offsets into the %hi/%lo references to constant
pool addresses as well.
* When in V9 mode, register allocate %icc[0-3].
* Add support for isel'ing UMUL_LOHI instead of marking it as Expand.
* Emit the 'Branch on Integer Register with Prediction' instructions. It's
not clear how to write a pattern for this though:
float %t1(int %a, int* %p) {
%C = seteq int %a, 0
br bool %C, label %T, label %F
T:
store int 123, int* %p
br label %F
F:
ret float undef
}
codegens to this:
t1:
save -96, %o6, %o6
1) subcc %i0, 0, %l0
1) bne .LBBt1_2 ! F
nop
.LBBt1_1: ! T
or %g0, 123, %l0
st %l0, [%i1]
.LBBt1_2: ! F
restore %g0, %g0, %g0
retl
nop
1) should be replaced with a brz in V9 mode.
* Same as above, but emit conditional move on register zero (p192) in V9
mode. Testcase:
int %t1(int %a, int %b) {
%C = seteq int %a, 0
%D = select bool %C, int %a, int %b
ret int %D
}
* Emit MULX/[SU]DIVX instructions in V9 mode instead of fiddling
with the Y register, if they are faster.
* Codegen bswap(load)/store(bswap) -> load/store ASI
* Implement frame pointer elimination, e.g. eliminate save/restore for
leaf fns.
* Fill delay slots