From 9aa1d44080df6bbe18f88d4bf3d1b5d824126032 Mon Sep 17 00:00:00 2001
From: Krzysztof Parzyszek <kparzysz@codeaurora.org>
Date: Tue, 2 May 2017 17:51:14 +0000
Subject: [PATCH] [Hexagon] Check for .cur def without use without using a map
 data structure

Patch by Colin LeMahieu.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@301943 91177308-0d34-0410-b5e6-96231b3b80d8
---
 .../Hexagon/MCTargetDesc/HexagonMCChecker.cpp      | 57 ++++++++++++++--------
 lib/Target/Hexagon/MCTargetDesc/HexagonMCChecker.h |  9 ++--
 2 files changed, 42 insertions(+), 24 deletions(-)

diff --git a/lib/Target/Hexagon/MCTargetDesc/HexagonMCChecker.cpp b/lib/Target/Hexagon/MCTargetDesc/HexagonMCChecker.cpp
index 33d73f1819c..f138a7c3e2f 100644
--- a/lib/Target/Hexagon/MCTargetDesc/HexagonMCChecker.cpp
+++ b/lib/Target/Hexagon/MCTargetDesc/HexagonMCChecker.cpp
@@ -159,12 +159,6 @@ void HexagonMCChecker::init(MCInst const &MCI) {
                isPredicateRegister(*SRI))
         // Some insns produce predicates too late to be used in the same packet.
         LatePreds.insert(*SRI);
-      else if (i == 0 && HexagonMCInstrInfo::isCVINew(MCII, MCI) &&
-               MCID.mayLoad())
-        // Current loads should be used in the same packet.
-        // TODO: relies on the impossibility of a current and a temporary loads
-        // in the same packet.
-        CurDefs.insert(*SRI), Defs[*SRI].insert(PredSense(PredReg, isTrue));
       else if (i == 0 && llvm::HexagonMCInstrInfo::getType(MCII, MCI) ==
                              HexagonII::TypeCVI_VM_TMP_LD)
         // Temporary loads should be used in the same packet, but don't commit
@@ -252,6 +246,7 @@ bool HexagonMCChecker::check(bool FullCheck) {
   bool chkNV = checkNewValues();
   bool chkR = checkRegisters();
   bool chkRRO = checkRegistersReadOnly();
+  checkRegisterCurDefs();
   bool chkS = checkSolo();
   bool chkSh = true;
   if (FullCheck)
@@ -396,6 +391,43 @@ bool HexagonMCChecker::checkRegistersReadOnly() {
   return true;
 }
 
+bool HexagonMCChecker::registerUsed(MCInst const &Inst, unsigned Register) {
+  if (HexagonMCInstrInfo::isDuplex(MCII, Inst)) {
+    if (registerUsed(*Inst.getOperand(0).getInst(), Register) ||
+        registerUsed(*Inst.getOperand(1).getInst(), Register))
+      return true;
+  } else {
+    unsigned Defs = HexagonMCInstrInfo::getDesc(MCII, Inst).getNumDefs();
+    for (unsigned j = Defs, n = Inst.getNumOperands(); j < n; ++j) {
+      MCOperand const &Operand = Inst.getOperand(j);
+      if (Operand.isReg() && Operand.getReg() == Register)
+        return true;
+    }
+  }
+  return false;
+}
+
+bool HexagonMCChecker::registerUsed(unsigned Register) {
+  auto Range = HexagonMCInstrInfo::bundleInstructions(MCB);
+  return std::any_of(Range.begin(), Range.end(), [&](MCOperand const &Operand) {
+    return registerUsed(*Operand.getInst(), Register);
+  });
+}
+
+void HexagonMCChecker::checkRegisterCurDefs() {
+  for (auto const &I : HexagonMCInstrInfo::bundleInstructions(MCB)) {
+    MCInst const &Inst = *I.getInst();
+    if (HexagonMCInstrInfo::isCVINew(MCII, Inst) &&
+        HexagonMCInstrInfo::getDesc(MCII, Inst).mayLoad()) {
+      unsigned Register = Inst.getOperand(0).getReg();
+      if (!registerUsed(Register))
+        reportWarning("Register `" + llvm::Twine(RI.getName(Register)) +
+                      "' used with `.cur' "
+                      "but not used in the same packet");
+    }
+  }
+}
+
 // Check for legal register uses and definitions.
 bool HexagonMCChecker::checkRegisters() {
   // Check for proper register definitions.
@@ -456,19 +488,6 @@ bool HexagonMCChecker::checkRegisters() {
     }
   }
 
-  // Check for use of current definitions.
-  for (const auto &I : CurDefs) {
-    unsigned R = I;
-
-    if (!Uses.count(R)) {
-      // Warn on an unused current definition.
-      reportWarning("register `" + llvm::Twine(RI.getName(R)) +
-                    "' used with `.cur' "
-                    "but not used in the same packet");
-      return true;
-    }
-  }
-
   // Check for use of temporary definitions.
   for (const auto &I : TmpDefs) {
     unsigned R = I;
diff --git a/lib/Target/Hexagon/MCTargetDesc/HexagonMCChecker.h b/lib/Target/Hexagon/MCTargetDesc/HexagonMCChecker.h
index d0238691cdc..c67a217afbe 100644
--- a/lib/Target/Hexagon/MCTargetDesc/HexagonMCChecker.h
+++ b/lib/Target/Hexagon/MCTargetDesc/HexagonMCChecker.h
@@ -78,10 +78,6 @@ class HexagonMCChecker {
   typedef std::set<unsigned>::iterator SoftDefsIterator;
   std::set<unsigned> SoftDefs;
 
-  /// Set of current definitions committed to the register file.
-  typedef std::set<unsigned>::iterator CurDefsIterator;
-  std::set<unsigned> CurDefs;
-
   /// Set of temporary definitions not committed to the register file.
   typedef std::set<unsigned>::iterator TmpDefsIterator;
   std::set<unsigned> TmpDefs;
@@ -109,13 +105,16 @@ class HexagonMCChecker {
   void init();
   void init(MCInst const &);
   void initReg(MCInst const &, unsigned, unsigned &PredReg, bool &isTrue);
-
+  
+  bool registerUsed(unsigned Register);
+  bool registerUsed(MCInst const &Inst, unsigned Register);
   // Checks performed.
   bool checkBranches();
   bool checkPredicates();
   bool checkNewValues();
   bool checkRegisters();
   bool checkRegistersReadOnly();
+  void checkRegisterCurDefs();
   bool checkSolo();
   bool checkShuffle();
   bool checkSlots();
-- 
2.11.0