Roman Lebedev 8360c42e25 [InstCombine] foldICmpBinOp(): consider inverted check in 'unsigned sub overflow' check ... A follow-up for r329011. This may be changed to produce @llvm.sub.with.overflow in a later patch, but for now just make things more consistent overall. A few observations stem from this: * There does not seem to be a similar one-instruction fold for uadd-overflow * I'm not sure we'll want to canonicalize `B u> A` as `usub.with.overflow`, so since the `icmp` here no longer refers to `sub`, reconstructing `usub.with.overflow` will be problematic, and will likely require standalone pass (similar to DivRemPairs). https://rise4fun.com/Alive/Zqs Name: (A - B) u> A --> B u> A %t0 = sub i8 %A, %B %r = icmp ugt i8 %t0, %A => %r = icmp ugt i8 %B, %A Name: (A - B) u<= A --> B u<= A %t0 = sub i8 %A, %B %r = icmp ule i8 %t0, %A => %r = icmp ule i8 %B, %A Name: C u< (C - D) --> C u< D %t0 = sub i8 %C, %D %r = icmp ult i8 %C, %t0 => %r = icmp ult i8 %C, %D Name: C u>= (C - D) --> C u>= D %t0 = sub i8 %C, %D %r = icmp uge i8 %C, %t0 => %r = icmp uge i8 %C, %D llvm-svn: 371101		2019-09-05 17:41:02 +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	[llvm] Migrate llvm::make_unique to std::make_unique	2019-08-15 15:54:37 +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	[Attributor][Stats] Use the right statistics macro	2019-09-04 20:34:57 +00:00
InstCombine	[InstCombine] foldICmpBinOp(): consider inverted check in 'unsigned sub overflow' check	2019-09-05 17:41:02 +00:00
Instrumentation	[PGO][CHR] Speed up following long, interlinked use-def chains.	2019-09-05 16:56:55 +00:00
ObjCARC	[ObjC][ARC] Delete ObjC runtime calls on global variables annotated	2019-06-14 22:06:32 +00:00
Scalar	[MergedLoadStoreMotion] Sink stores to BB with more than 2 predecessors	2019-09-05 17:00:32 +00:00
Utils	[MemorySSA] Verify MSSAUpdater exists.	2019-09-05 16:58:15 +00:00
Vectorize	[LLVM][Alignment] Convert isLegalNTStore/isLegalNTLoad to llvm::Align	2019-09-05 13:09:42 +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