llvm-project/llvm/lib/Transforms
Sanjay Patel e8bf0f79bd [InstCombine] canonicalize more unsigned saturated add with 'not'
Yet another pattern variation suggested by:
https://bugs.llvm.org/show_bug.cgi?id=14613

There are 8 more potential commuted patterns here on top of the
8 that were already handled (rL354221, rL354276, rL354393).
We have the obvious commute of the 'add' + commute of the cmp
predicate/operands (ugt/ult) + commute of the select operands:

Name: base
%notx = xor i32 %x, -1
%a = add i32 %notx, %y
%c = icmp ult i32 %x, %y
%r = select i1 %c, i32 -1, i32 %a
=>
%c2 = icmp ult i32 %a, %y
%r = select i1 %c2, i32 -1, i32 %a

Name: ugt
%notx = xor i32 %x, -1
%a = add i32 %notx, %y
%c = icmp ugt i32 %y, %x
%r = select i1 %c, i32 -1, i32 %a
=>
%c2 = icmp ult i32 %a, %y
%r = select i1 %c2, i32 -1, i32 %a

Name: commute select
%notx = xor i32 %x, -1
%a = add i32 %notx, %y
%c = icmp ult i32 %y, %x
%r = select i1 %c, i32 %a, i32 -1
=>
%c2 = icmp ult i32 %a, %y
%r = select i1 %c2, i32 -1, i32 %a

Name: ugt + commute select
%notx = xor i32 %x, -1
%a = add i32 %notx, %y
%c = icmp ugt i32 %x, %y
%r = select i1 %c, i32 %a, i32 -1
=>
%c2 = icmp ult i32 %a, %y
%r = select i1 %c2, i32 -1, i32 %a

https://rise4fun.com/Alive/den

llvm-svn: 354887
2019-02-26 15:18:49 +00:00
..
AggressiveInstCombine Update the file headers across all of the LLVM projects in the monorepo 2019-01-19 08:50:56 +00:00
Coroutines [opaque pointer types] Pass value type to LoadInst creation. 2019-02-01 20:44:24 +00:00
Hello Update the file headers across all of the LLVM projects in the monorepo 2019-01-19 08:50:56 +00:00
IPO [Inliner] Pass nullptr for the ORE param of getInlineCost if RemarkEnabled 2019-02-21 02:57:52 +00:00
InstCombine [InstCombine] canonicalize more unsigned saturated add with 'not' 2019-02-26 15:18:49 +00:00
Instrumentation [Instrumentation][NFC] Fix warning. 2019-02-14 12:10:49 +00:00
ObjCARC [opaque pointer types] Pass function type for CallBase::setCalledFunction. 2019-02-01 20:44:54 +00:00
Scalar [DTU] Refine the interface and logic of applyUpdates 2019-02-22 13:48:38 +00:00
Utils BreakCriticalEdges: Update PostDominatorTree 2019-02-22 15:01:41 +00:00
Vectorize [Vectorizer] Add vectorization support for fixed smul/umul intrinsics 2019-02-25 15:42:02 +00:00
CMakeLists.txt Another try to commit 323321 (aggressive instruction combine). 2018-01-25 12:06:32 +00:00
LLVMBuild.txt Update the file headers across all of the LLVM projects in the monorepo 2019-01-19 08:50:56 +00:00