uniform analysis cross-loop def-use random

add another condition for def-use affected by divergent-branch

IGC/AdaptorCommon/DivergentBarrierPass.cpp

@@ -29,6 +29,7 @@ SPDX-License-Identifier: MIT
 #include "llvmWrapper/IR/DerivedTypes.h"
 #include "llvm/IR/Module.h"
 #include "llvm/IR/InstIterator.h"
+#include "llvm/Analysis/LoopInfo.h"
 #include "llvm/Analysis/PostDominators.h"
 #include "llvm/IR/Dominators.h"
 #include "llvm/IR/Verifier.h"
@@ -96,10 +97,11 @@ bool DivergentBarrierPass::hasDivergentBarrier(
 
  PostDominatorTree PDT(*F);
  DominatorTree DT(*F);
+ LoopInfo LI(DT);
 
  TranslationTable TT;
  TT.run(*F);
- WIAnalysisRunner WI(F, &DT, &PDT, m_MDUtils, m_CGCtx, ModMD, &TT);
+ WIAnalysisRunner WI(F, &LI, &DT, &PDT, m_MDUtils, m_CGCtx, ModMD, &TT);
  WI.run();
 
  return llvm::any_of(Barriers, [&](Instruction* I) {

IGC/Compiler/CISACodeGen/VectorPreProcess.cpp

@@ -357,6 +357,7 @@ namespace
  AU.addRequired<MetaDataUtilsWrapper>();
  AU.addRequired<DominatorTreeWrapperPass>();
  AU.addRequired<PostDominatorTreeWrapperPass>();
+ AU.addRequired<LoopInfoWrapperPass>();
  }
 
  private:
@@ -1809,12 +1810,14 @@ bool VectorPreProcess::runOnFunction(Function& F)
  &getAnalysis<DominatorTreeWrapperPass>().getDomTree();
  auto* PDT =
  &getAnalysis<PostDominatorTreeWrapperPass>().getPostDomTree();
+ auto *LI =
+ &getAnalysis<LoopInfoWrapperPass>().getLoopInfo();
  auto* ModMD =
  getAnalysis<MetaDataUtilsWrapper>().getModuleMetaData();
 
  TranslationTable TT;
  TT.run(F);
- WIAnalysisRunner WI(&F, DT, PDT, MDUtils, m_CGCtx, ModMD, &TT);
+ WIAnalysisRunner WI(&F, LI, DT, PDT, MDUtils, m_CGCtx, ModMD, &TT);
  WI.run();
 
  for (uint32_t i = 0; i < m_WorkList.size(); ++i)

IGC/Compiler/CISACodeGen/WIAnalysis.cpp

@@ -274,6 +274,7 @@ void WIAnalysisRunner::dump() const
 
 void WIAnalysisRunner::init(
  llvm::Function* F,
+ llvm::LoopInfo* LI,
  llvm::DominatorTree* DT,
  llvm::PostDominatorTree* PDT,
  IGC::IGCMD::MetaDataUtils* MDUtils,
@@ -282,6 +283,7 @@ void WIAnalysisRunner::init(
  IGC::TranslationTable* TransTable)
 {
  m_func = F;
+ this->LI = LI;
  this->DT = DT;
  this->PDT = PDT;
  m_pMdUtils = MDUtils;
@@ -381,11 +383,12 @@ bool WIAnalysis::runOnFunction(Function& F)
  auto* MDUtils = getAnalysis<MetaDataUtilsWrapper>().getMetaDataUtils();
  auto* DT = &getAnalysis<DominatorTreeWrapperPass>().getDomTree();
  auto* PDT = &getAnalysis<PostDominatorTreeWrapperPass>().getPostDomTree();
- auto* CGCtx = getAnalysis<CodeGenContextWrapper>().getCodeGenContext();
+ auto *LI = &getAnalysis<LoopInfoWrapperPass>().getLoopInfo();
+ auto *CGCtx = getAnalysis<CodeGenContextWrapper>().getCodeGenContext();
  auto* ModMD = getAnalysis<MetaDataUtilsWrapper>().getModuleMetaData();
  auto* pTT = &getAnalysis<TranslationTable>();
 
- Runner.init(&F, DT, PDT, MDUtils, CGCtx, ModMD, pTT);
+ Runner.init(&F, LI, DT, PDT, MDUtils, CGCtx, ModMD, pTT);
  return Runner.run();
 }
 
@@ -911,17 +914,47 @@ void WIAnalysisRunner::update_cf_dep(const IGCLLVM::TerminatorInst* inst)
  BranchInfo br_info(inst, ipd);
  // debug: dump influence region and partial-joins
  // br_info.print(ods());
-
+ auto* CbrLoop = LI->getLoopFor(blk);
+ // Loop* IPDLoop = nullptr;
  // check dep-type for every phi in the full join
  if (ipd)
  {
  updatePHIDepAtJoin(ipd, &br_info);
+ // IPDLoop = LI->getLoopFor(ipd);
  }
  // check dep-type for every phi in the partial-joins
  for (SmallPtrSet<BasicBlock*, 4>::iterator join_it = br_info.partial_joins.begin(),
  join_e = br_info.partial_joins.end(); join_it != join_e; ++join_it)
  {
- updatePHIDepAtJoin(*join_it, &br_info);
+ auto *PJ = *join_it;
+ // skip the special loop-entry case
+ if (DT->dominates(PJ, blk)) {
+ int NumPreds = 0;
+ for (auto *pred : predecessors(PJ)) {
+ if (br_info.influence_region.count(pred)) {
+ NumPreds++;
+ }
+ }
+ if (NumPreds <= 1)
+ continue;
+ }
+ auto PJDom = DT->getNode(PJ)->getIDom()->getBlock();
+ // If both partial-join and it IDom are in partial-join region
+ // there are cases in which phi-nodes in partial-joins are not
+ // relevant to the cbr under the investigation
+ auto LoopA = LI->getLoopFor(PJDom);
+ //auto LoopB = LI->getLoopFor(PJ);
+ if (br_info.partial_joins.count(PJDom))
+ {
+ // both PJ and its IDom are outside the CBR loop
+ if (!CbrLoop || !CbrLoop->contains(LoopA))
+ continue;
+ // cbr and its IPD are at the same loop level
+ // the influence region can be considered as a DAG
+ // if (IPDLoop == CbrLoop)
+ // continue;
+ }
+ updatePHIDepAtJoin(PJ, &br_info);
  }
 
  // walk through all the instructions in the influence-region
@@ -970,6 +1003,7 @@ void WIAnalysisRunner::update_cf_dep(const IGCLLVM::TerminatorInst* inst)
  // 1) if use is in the full-join
  // 2) if use is even outside the full-join
  // 3) if use is in partial-join but def is not in partial-join
+ // 4) if def and use are in partial-join but def inside loop
  Value::use_iterator use_it = defi->use_begin();
  Value::use_iterator use_e = defi->use_end();
  for (; use_it != use_e; ++use_it)
@@ -989,10 +1023,14 @@ void WIAnalysisRunner::update_cf_dep(const IGCLLVM::TerminatorInst* inst)
  // local def-use, not related to control-dependence
  continue; // skip
  }
+ auto DefLoop = LI->getLoopFor(def_blk);
+ auto UseLoop = LI->getLoopFor(user_blk);
  if (user_blk == br_info.full_join ||
  !br_info.influence_region.count(user_blk) ||
  (br_info.partial_joins.count(user_blk) &&
- !br_info.partial_joins.count(def_blk))
+ (!br_info.partial_joins.count(def_blk) ||
+ (DefLoop && !DefLoop->contains(UseLoop)))
+ )
  )
  {
  updateDepMap(defi, instDep);

IGC/Compiler/CISACodeGen/WIAnalysis.hpp

@@ -27,6 +27,7 @@ SPDX-License-Identifier: MIT
 #include <llvm/IR/Value.h>
 #include <llvm/IR/InstIterator.h>
 #include <llvm/IR/Dominators.h>
+#include <llvm/Analysis/LoopInfo.h>
 #include <llvm/Analysis/PostDominators.h>
 #include "common/LLVMWarningsPop.hpp"
 
@@ -78,6 +79,7 @@ namespace IGC
  public:
  void init(
  llvm::Function* F,
+ llvm::LoopInfo* LI,
  llvm::DominatorTree* DT,
  llvm::PostDominatorTree* PDT,
  IGCMD::MetaDataUtils* MDUtils,
@@ -87,14 +89,15 @@ namespace IGC
 
  WIAnalysisRunner(
  llvm::Function* F,
+ llvm::LoopInfo* LI,
  llvm::DominatorTree* DT,
  llvm::PostDominatorTree* PDT,
  IGCMD::MetaDataUtils* MDUtils,
  CodeGenContext* CGCtx,
  ModuleMetaData* ModMD,
  TranslationTable* TransTable)
  {
- init(F, DT, PDT, MDUtils, CGCtx, ModMD, TransTable);
+ init(F, LI, DT, PDT, MDUtils, CGCtx, ModMD, TransTable);
  }
 
  WIAnalysisRunner() {}
@@ -247,12 +250,6 @@ namespace IGC
  bool& IsLzUniform);
 
  private:
-#ifdef OCL_SPECIFIC
- // @brief pointer to Soa alloca analysis performed for this function
- SoaAllocaAnalysis* m_soaAllocaAnalysis = nullptr;
- /// Runtime services pointer
- RuntimeServices* m_rtServices = nullptr;
-#endif
 
  /// The WIAnalysis follows pointer arithmetic
  /// and Index arithmetic when calculating dependency
@@ -281,6 +278,7 @@ namespace IGC
  std::vector<const llvm::Value*> m_forcedUniforms;
 
  llvm::Function* m_func = nullptr;
+ llvm::LoopInfo *LI = nullptr;
  llvm::DominatorTree* DT = nullptr;
  llvm::PostDominatorTree* PDT = nullptr;
  IGC::IGCMD::MetaDataUtils* m_pMdUtils = nullptr;
@@ -325,11 +323,9 @@ namespace IGC
  {
  // Analysis pass preserve all
  AU.setPreservesAll();
-#ifdef OCL_SPECIFIC
- AU.addRequired<SoaAllocaAnalysis>();
-#endif
  AU.addRequired<llvm::DominatorTreeWrapperPass>();
  AU.addRequired<llvm::PostDominatorTreeWrapperPass>();
+ AU.addRequired<llvm::LoopInfoWrapperPass>();
  AU.addRequired<MetaDataUtilsWrapper>();
  AU.addRequired<CodeGenContextWrapper>();
  AU.addRequired<TranslationTable>();