From 7d615b50bb994842ce7d7806300ae746a8a9c697 Mon Sep 17 00:00:00 2001
From: Fred Chow <fredchow@gitee.com>
Date: Thu, 27 May 2021 17:24:33 -0700
Subject: [PATCH] Include more types of opcodes in strength reduction; run hdse
 phase after strength reduction; mark as SR candidate only if occuring in
 loops

---
 src/mapleall/maple_me/include/me_hdse.h   |  3 +++
 src/mapleall/maple_me/src/me_ir.cpp       | 16 ++++++++++++++--
 src/mapleall/maple_me/src/me_ssa_epre.cpp | 13 +++++++++++++
 src/mapleall/maple_me/src/ssa_pre.cpp     |  2 +-
 4 files changed, 31 insertions(+), 3 deletions(-)

diff --git a/src/mapleall/maple_me/include/me_hdse.h b/src/mapleall/maple_me/include/me_hdse.h
index a8434b1b63..7b9dab50f7 100644
--- a/src/mapleall/maple_me/include/me_hdse.h
+++ b/src/mapleall/maple_me/include/me_hdse.h
@@ -31,6 +31,9 @@ class MeHDSE : public HDSE {
 
   virtual ~MeHDSE() = default;
   void BackwardSubstitution();
+  std::string PhaseName() const {
+    return "hdse";
+  }
 };
 
 class MeDoHDSE : public MeFuncPhase {
diff --git a/src/mapleall/maple_me/src/me_ir.cpp b/src/mapleall/maple_me/src/me_ir.cpp
index c257bf5317..87d89bd04e 100644
--- a/src/mapleall/maple_me/src/me_ir.cpp
+++ b/src/mapleall/maple_me/src/me_ir.cpp
@@ -568,14 +568,26 @@ MeExpr *OpMeExpr::GetIdenticalExpr(MeExpr &expr, bool isConstructor) const {
 }
 
 bool OpMeExpr::StrengthReducible() {
-  if (op != OP_mul || !IsPrimitiveInteger(primType)) {
+  if (!IsPrimitiveInteger(primType)) {
     return false;
   }
-  return GetOpnd(1)->GetOp() == OP_constval;
+  switch (op) {
+    case OP_cvt: {
+      return IsPrimitiveInteger(opndType) && GetPrimTypeSize(primType) >= GetPrimTypeSize(opndType);
+    }
+    case OP_mul:
+      return GetOpnd(1)->GetOp() == OP_constval;
+    case OP_add:
+      return true;
+    default: return false;
+  }
 }
 
 int64 OpMeExpr::SRMultiplier() {
   ASSERT(StrengthReducible(), "OpMeExpr::SRMultiplier: operation is not strength reducible");
+  if (op != OP_mul) {
+    return 1;
+  }
   MIRConst *constVal = static_cast<ConstMeExpr *>(GetOpnd(1))->GetConstVal();
   ASSERT(constVal->GetKind() == kConstInt, "OpMeExpr::SRMultiplier: multiplier not an integer constant");
   return static_cast<MIRIntConst *>(constVal)->GetValueUnderType();
diff --git a/src/mapleall/maple_me/src/me_ssa_epre.cpp b/src/mapleall/maple_me/src/me_ssa_epre.cpp
index 737ea7ee76..a7badd23c1 100644
--- a/src/mapleall/maple_me/src/me_ssa_epre.cpp
+++ b/src/mapleall/maple_me/src/me_ssa_epre.cpp
@@ -16,6 +16,8 @@
 #include "me_dominance.h"
 #include "me_ssa_update.h"
 #include "me_placement_rc.h"
+#include "me_loop_analysis.h"
+#include "me_hdse.h"
 
 namespace {
 const std::set<std::string> propWhiteList {
@@ -74,6 +76,9 @@ AnalysisResult *MeDoSSAEPre::Run(MeFunction *func, MeFuncResultMgr *m, ModuleRes
     kh = static_cast<KlassHierarchy*>(mrm->GetAnalysisResult(MoPhase_CHA, &func->GetMIRModule()));
     CHECK_FATAL(kh != nullptr, "KlassHierarchy phase has problem");
   }
+  auto *identLoops = static_cast<IdentifyLoops*>(m->GetAnalysisResult(MeFuncPhase_MELOOP, func));
+  CHECK_NULL_FATAL(identLoops);
+
   bool eprePULimitSpecified = MeOption::eprePULimit != UINT32_MAX;
   uint32 epreLimitUsed =
       (eprePULimitSpecified && puCount != MeOption::eprePULimit) ? UINT32_MAX : MeOption::epreLimit;
@@ -109,6 +114,14 @@ AnalysisResult *MeDoSSAEPre::Run(MeFunction *func, MeFuncResultMgr *m, ModuleRes
     placeRC.preKind = MeSSUPre::kSecondDecrefPre;
     placeRC.ApplySSUPre();
   }
+  if (MeOption::strengthReduction) { // for deleting redundant injury repairs
+    MeHDSE hdse(*func, *dom, *func->GetIRMap(), DEBUGFUNC(func));
+    if (!MeOption::quiet) {
+      LogInfo::MapleLogger() << "  == " << PhaseName() << " invokes [ " << hdse.PhaseName() << " ] ==\n";
+    }
+    hdse.hdseKeepRef = MeOption::dseKeepRef;
+    hdse.DoHDSE();
+  }
   if (DEBUGFUNC(func)) {
     LogInfo::MapleLogger() << "\n============== EPRE =============" << "\n";
     func->Dump(false);
diff --git a/src/mapleall/maple_me/src/ssa_pre.cpp b/src/mapleall/maple_me/src/ssa_pre.cpp
index db02549cf7..41036e7273 100644
--- a/src/mapleall/maple_me/src/ssa_pre.cpp
+++ b/src/mapleall/maple_me/src/ssa_pre.cpp
@@ -1322,7 +1322,7 @@ MeRealOcc *SSAPre::CreateRealOcc(MeStmt &meStmt, int seqStmt, MeExpr &meExpr, bo
     MIRType *ty = GlobalTables::GetTypeTable().GetTypeFromTyIdx(fldPair.first);
     bool isFinal = fldPair.second.GetAttr(FLDATTR_final);
     wkCand->SetNeedLocalRefVar(ty->GetPrimType() == PTY_ref && !isFinal);
-  } else if (strengthReduction && meExpr.StrengthReducible()) {
+  } else if (strengthReduction && meExpr.StrengthReducible() && meStmt.GetBB()->GetAttributes(kBBAttrIsInLoop)) {
     wkCand->isSRCand = true;
   }
   workList.push_back(wkCand);
-- 
Gitee