From 9a16d655c71826bef98b7d6e9590e4494ac0e1a9 Mon Sep 17 00:00:00 2001 From: Wei Mi Date: Wed, 13 Apr 2016 03:08:27 +0000 Subject: Recommit r265547, and r265610,r265639,r265657 on top of it, plus two fixes with one about error verify-regalloc reported, and another about live range update of phi after rematerialization. r265547: Replace analyzeSiblingValues with new algorithm to fix its compile time issue. The patch is to solve PR17409 and its duplicates. analyzeSiblingValues is a N x N complexity algorithm where N is the number of siblings generated by reg splitting. Although it causes siginificant compile time issue when N is large, it is also important for performance since it removes redundent spills and enables rematerialization. To solve the compile time issue, the patch removes analyzeSiblingValues and replaces it with lower cost alternatives containing two parts. The first part creates a new spill hoisting method in postOptimization of register allocation. It does spill hoisting at once after all the spills are generated instead of inside every instance of selectOrSplit. The second part queries the define expr of the original register for rematerializaiton and keep it always available during register allocation even if it is already dead. It deletes those dead instructions only in postOptimization. With the two parts in the patch, it can remove analyzeSiblingValues without sacrificing performance. Patches on top of r265547: r265610 "Fix the compare-clang diff error introduced by r265547." r265639 "Fix the sanitizer bootstrap error in r265547." r265657 "InlineSpiller.cpp: Escap \@ in r265547. [-Wdocumentation]" Differential Revision: http://reviews.llvm.org/D15302 Differential Revision: http://reviews.llvm.org/D18934 Differential Revision: http://reviews.llvm.org/D18935 Differential Revision: http://reviews.llvm.org/D18936 llvm-svn: 266162 --- llvm/lib/CodeGen/RegAllocBase.cpp | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'llvm/lib/CodeGen/RegAllocBase.cpp') diff --git a/llvm/lib/CodeGen/RegAllocBase.cpp b/llvm/lib/CodeGen/RegAllocBase.cpp index 16ff48e78a7..1130d64689d 100644 --- a/llvm/lib/CodeGen/RegAllocBase.cpp +++ b/llvm/lib/CodeGen/RegAllocBase.cpp @@ -153,3 +153,12 @@ void RegAllocBase::allocatePhysRegs() { } } } + +void RegAllocBase::postOptimization() { + spiller().postOptimization(); + for (auto DeadInst : DeadRemats) { + LIS->RemoveMachineInstrFromMaps(*DeadInst); + DeadInst->eraseFromParent(); + } + DeadRemats.clear(); +} -- cgit v1.2.3