From 846b31d74aa673a178f57f9d47f366d8ddb756d3 Mon Sep 17 00:00:00 2001
From: Andrew Trick <atrick@apple.com>
Date: Fri, 30 Aug 2013 17:58:49 +0000
Subject: [PATCH] Use LiveRangeQuery for instruction-level liveness queries.

Remove redundant or bug-prone LiveInterval APIs.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@189685 91177308-0d34-0410-b5e6-96231b3b80d8
---
 include/llvm/CodeGen/LiveInterval.h | 15 ---------------
 lib/CodeGen/LiveRangeEdit.cpp       |  2 +-
 lib/CodeGen/RegisterPressure.cpp    | 14 ++++++++------
 3 files changed, 9 insertions(+), 22 deletions(-)

diff --git a/include/llvm/CodeGen/LiveInterval.h b/include/llvm/CodeGen/LiveInterval.h
index 38d07e4612b..84323deef83 100644
--- a/include/llvm/CodeGen/LiveInterval.h
+++ b/include/llvm/CodeGen/LiveInterval.h
@@ -287,21 +287,6 @@ namespace llvm {
       return r != end() && r->start <= index;
     }
 
-    /// Return true if a live range ends at the instruction at this index. Note
-    /// that the kill point is not contained in the half-open live range. It is
-    /// usually the EarlyClobber or Register slot following its last use.
-    bool isKilledAtInstr(SlotIndex index) const {
-      SlotIndex BaseIdx = index.getBaseIndex();
-      const_iterator r = find(BaseIdx);
-      return r != end() && r->end.getBaseIndex() == BaseIdx;
-    }
-
-    /// Return true if a live range starts at the instruction at this index.
-    bool isDefinedByInstr(SlotIndex index) const {
-      const_iterator r = find(index.getDeadSlot());
-      return r != end() && r->end.getBaseIndex() == index.getBaseIndex();
-    }
-
     /// getLiveRangeContaining - Return the live range that contains the
     /// specified index, or null if there is none.
     const LiveRange *getLiveRangeContaining(SlotIndex Idx) const {
diff --git a/lib/CodeGen/LiveRangeEdit.cpp b/lib/CodeGen/LiveRangeEdit.cpp
index 86271116f4e..9c374b15019 100644
--- a/lib/CodeGen/LiveRangeEdit.cpp
+++ b/lib/CodeGen/LiveRangeEdit.cpp
@@ -278,7 +278,7 @@ void LiveRangeEdit::eliminateDeadDef(MachineInstr *MI, ToShrinkSet &ToShrink) {
     // Always shrink COPY uses that probably come from live range splitting.
     if (MI->readsVirtualRegister(Reg) &&
         (MI->isCopy() || MOI->isDef() || MRI.hasOneNonDBGUse(Reg) ||
-         LI.isKilledAtInstr(Idx)))
+         LiveRangeQuery(LI, Idx).isKill()))
       ToShrink.insert(&LI);
 
     // Remove defined value.
diff --git a/lib/CodeGen/RegisterPressure.cpp b/lib/CodeGen/RegisterPressure.cpp
index 1be203f36dd..27da370c961 100644
--- a/lib/CodeGen/RegisterPressure.cpp
+++ b/lib/CodeGen/RegisterPressure.cpp
@@ -500,8 +500,9 @@ bool RegPressureTracker::recede(SmallVectorImpl<unsigned> *LiveUses,
       if (RequireIntervals) {
         const LiveInterval *LI = getInterval(Reg);
         // Check if this LR is killed and not redefined here.
-        if (LI && !LI->isKilledAtInstr(SlotIdx)
-            && !LI->isDefinedByInstr(SlotIdx)) {
+        if (LI) {
+          LiveRangeQuery LRQ(*LI, SlotIdx);
+          if (!LRQ.isKill() && !LRQ.valueDefined())
             discoverLiveOut(Reg);
         }
       }
@@ -558,7 +559,7 @@ bool RegPressureTracker::advance() {
     bool lastUse = false;
     if (RequireIntervals) {
       const LiveInterval *LI = getInterval(Reg);
-      lastUse = LI && LI->isKilledAtInstr(SlotIdx);
+      lastUse = LI && LiveRangeQuery(*LI, SlotIdx).isKill();
     }
     else {
       // Allocatable physregs are always single-use before register rewriting.
@@ -882,9 +883,10 @@ void RegPressureTracker::bumpDownwardPressure(const MachineInstr *MI) {
       // to be bottom-scheduled to avoid searching uses at each query.
       SlotIndex CurrIdx = getCurrSlot();
       const LiveInterval *LI = getInterval(Reg);
-      if (LI && LI->isKilledAtInstr(SlotIdx)
-          && !findUseBetween(Reg, CurrIdx, SlotIdx, MRI, LIS)) {
-        decreaseRegPressure(Reg);
+      if (LI) {
+        LiveRangeQuery LRQ(*LI, SlotIdx);
+        if (LRQ.isKill() && !findUseBetween(Reg, CurrIdx, SlotIdx, MRI, LIS))
+          decreaseRegPressure(Reg);
       }
     }
     else if (!TargetRegisterInfo::isVirtualRegister(Reg)) {
-- 
2.34.1