mirror of
https://github.com/c64scene-ar/llvm-6502.git
synced 2024-08-21 03:29:40 +00:00
955f331a77
This is important for several reasons:
1. Benchmarks have lots of code that looks like this (perlbmk in particular):
%tmp.2.i = setne int %tmp.0.i, 128 ; <bool> [#uses=1]
%tmp.6343 = seteq int %tmp.0.i, 1 ; <bool> [#uses=1]
%tmp.63 = and bool %tmp.2.i, %tmp.6343 ; <bool> [#uses=1]
we now fold away the setne, a clear improvement.
2. In the more important cases, such as (X >= 10) & (X < 20), we now produce
smaller code: (X-10) < 10.
3. Perhaps the nicest effect of this patch is that it really helps out the
code generators. In particular, for a 'range test' like the above,
instead of generating this on X86 (the difference on PPC is even more
pronounced):
cmp %EAX, 50
setge %CL
cmp %EAX, 100
setl %AL
and %CL, %AL
cmp %CL, 0
we now generate this:
add %EAX, -50
cmp %EAX, 50
Furthermore, this causes setcc's to be folded into branches more often.
These combinations trigger dozens of times in the spec benchmarks, particularly
in 176.gcc, 186.crafty, 253.perlbmk, 254.gap, & 099.go.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16559 91177308-0d34-0410-b5e6-96231b3b80d8
|
||
|---|---|---|
| .. | ||
| ADCE.cpp | ||
| BasicBlockPlacement.cpp | ||
| ConstantProp.cpp | ||
| CorrelatedExprs.cpp | ||
| DCE.cpp | ||
| DeadStoreElimination.cpp | ||
| DecomposeMultiDimRefs.cpp | ||
| GCSE.cpp | ||
| IndVarSimplify.cpp | ||
| InstructionCombining.cpp | ||
| LICM.cpp | ||
| LoopUnroll.cpp | ||
| LoopUnswitch.cpp | ||
| LowerConstantExprs.cpp | ||
| LowerGC.cpp | ||
| LowerPacked.cpp | ||
| Makefile | ||
| PRE.cpp | ||
| Reassociate.cpp | ||
| ScalarReplAggregates.cpp | ||
| SCCP.cpp | ||
| SimplifyCFG.cpp | ||
| SymbolStripping.cpp | ||
| TailDuplication.cpp | ||
| TailRecursionElimination.cpp | ||