Revert commit 56835 since it breaks the build.

"If a re-materializable instruction has a register
operand, the spiller will change the register operand's
spill weight to HUGE_VAL to avoid it being spilled.
However, if the operand is already in the queue ready
to be spilled, avoid re-materializing it".


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@56837 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Duncan Sands 2008-09-30 10:00:30 +00:00
parent d41474d2c0
commit 46292be362
4 changed files with 8 additions and 105 deletions

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@ -819,7 +819,6 @@ bool LiveIntervals::isValNoAvailableAt(const LiveInterval &li, MachineInstr *MI,
/// val# of the specified interval is re-materializable.
bool LiveIntervals::isReMaterializable(const LiveInterval &li,
const VNInfo *ValNo, MachineInstr *MI,
SmallVectorImpl<LiveInterval*> &SpillIs,
bool &isLoad) {
if (DisableReMat)
return false;
@ -856,8 +855,8 @@ bool LiveIntervals::isReMaterializable(const LiveInterval &li,
// If the instruction accesses memory and the memory could be non-constant,
// assume the instruction is not rematerializable.
for (std::list<MachineMemOperand>::const_iterator
I = MI->memoperands_begin(), E = MI->memoperands_end(); I != E; ++I){
for (std::list<MachineMemOperand>::const_iterator I = MI->memoperands_begin(),
E = MI->memoperands_end(); I != E; ++I) {
const MachineMemOperand &MMO = *I;
if (MMO.isVolatile() || MMO.isStore())
return false;
@ -925,21 +924,13 @@ bool LiveIntervals::isReMaterializable(const LiveInterval &li,
if (!isValNoAvailableAt(ImpLi, MI, UseIdx))
return false;
}
// If a register operand of the re-materialized instruction is going to
// be spilled next, then it's not legal to re-materialize this instruction.
for (unsigned i = 0, e = SpillIs.size(); i != e; ++i)
if (ImpUse == SpillIs[i]->reg)
return false;
}
return true;
}
/// isReMaterializable - Returns true if every definition of MI of every
/// val# of the specified interval is re-materializable.
bool LiveIntervals::isReMaterializable(const LiveInterval &li,
SmallVectorImpl<LiveInterval*> &SpillIs,
bool &isLoad) {
bool LiveIntervals::isReMaterializable(const LiveInterval &li, bool &isLoad) {
isLoad = false;
for (LiveInterval::const_vni_iterator i = li.vni_begin(), e = li.vni_end();
i != e; ++i) {
@ -953,7 +944,7 @@ bool LiveIntervals::isReMaterializable(const LiveInterval &li,
MachineInstr *ReMatDefMI = getInstructionFromIndex(DefIdx);
bool DefIsLoad = false;
if (!ReMatDefMI ||
!isReMaterializable(li, VNI, ReMatDefMI, SpillIs, DefIsLoad))
!isReMaterializable(li, VNI, ReMatDefMI, DefIsLoad))
return false;
isLoad |= DefIsLoad;
}
@ -1737,7 +1728,6 @@ addIntervalsForSpillsFast(const LiveInterval &li,
std::vector<LiveInterval*> LiveIntervals::
addIntervalsForSpills(const LiveInterval &li,
SmallVectorImpl<LiveInterval*> &SpillIs,
const MachineLoopInfo *loopInfo, VirtRegMap &vrm,
float &SSWeight) {
@ -1841,7 +1831,7 @@ addIntervalsForSpills(const LiveInterval &li,
MachineInstr *ReMatDefMI = (DefIdx == ~0u)
? 0 : getInstructionFromIndex(DefIdx);
bool dummy;
if (ReMatDefMI && isReMaterializable(li, VNI, ReMatDefMI, SpillIs, dummy)) {
if (ReMatDefMI && isReMaterializable(li, VNI, ReMatDefMI, dummy)) {
// Remember how to remat the def of this val#.
ReMatOrigDefs[VN] = ReMatDefMI;
// Original def may be modified so we have to make a copy here.

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@ -879,9 +879,8 @@ void RALinScan::assignRegOrStackSlotAtInterval(LiveInterval* cur)
if (cur->weight != HUGE_VALF && cur->weight <= minWeight) {
DOUT << "\t\t\tspilling(c): " << *cur << '\n';
float SSWeight;
SmallVector<LiveInterval*, 8> spillIs;
std::vector<LiveInterval*> added =
li_->addIntervalsForSpills(*cur, spillIs, loopInfo, *vrm_, SSWeight);
li_->addIntervalsForSpills(*cur, loopInfo, *vrm_, SSWeight);
addStackInterval(cur, ls_, li_, SSWeight, *vrm_);
if (added.empty())
return; // Early exit if all spills were folded.
@ -932,7 +931,7 @@ void RALinScan::assignRegOrStackSlotAtInterval(LiveInterval* cur)
earliestStart = std::min(earliestStart, sli->beginNumber());
float SSWeight;
std::vector<LiveInterval*> newIs =
li_->addIntervalsForSpills(*sli, spillIs, loopInfo, *vrm_, SSWeight);
li_->addIntervalsForSpills(*sli, loopInfo, *vrm_, SSWeight);
addStackInterval(sli, ls_, li_, SSWeight, *vrm_);
std::copy(newIs.begin(), newIs.end(), std::back_inserter(added));
spilled.insert(sli->reg);

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@ -2361,8 +2361,7 @@ bool SimpleRegisterCoalescing::runOnMachineFunction(MachineFunction &fn) {
LI.weight = HUGE_VALF;
else {
bool isLoad = false;
SmallVector<LiveInterval*, 4> SpillIs;
if (li_->isReMaterializable(LI, SpillIs, isLoad)) {
if (li_->isReMaterializable(LI, isLoad)) {
// If all of the definitions of the interval are re-materializable,
// it is a preferred candidate for spilling. If non of the defs are
// loads, then it's potentially very cheap to re-materialize.

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@ -1,85 +0,0 @@
; RUN: llvm-as < %s | llc -mtriple=i386-apple-darwin -relocation-model=pic -disable-fp-elim
%struct..0objc_selector = type opaque
%struct.NSString = type opaque
%struct.XCStringList = type { i32, %struct._XCStringListNode* }
%struct._XCStringListNode = type { [3 x i8], [0 x i8], i8 }
%struct.__builtin_CFString = type { i32*, i32, i8*, i32 }
internal constant %struct.__builtin_CFString { i32* getelementptr ([0 x i32]* @__CFConstantStringClassReference, i32 0, i32 0), i32 1992, i8* getelementptr ([3 x i8]* @"\01LC", i32 0, i32 0), i32 2 } ; <%struct.__builtin_CFString*>:0 [#uses=1]
@__CFConstantStringClassReference = external global [0 x i32] ; <[0 x i32]*> [#uses=1]
@"\01LC" = internal constant [3 x i8] c"NO\00" ; <[3 x i8]*> [#uses=1]
@"\01LC1" = internal constant [1 x i8] zeroinitializer ; <[1 x i8]*> [#uses=1]
@llvm.used1 = appending global [1 x i8*] [ i8* bitcast (%struct.NSString* (%struct.XCStringList*, %struct..0objc_selector*)* @"-[XCStringList stringRepresentation]" to i8*) ], section "llvm.metadata" ; <[1 x i8*]*> [#uses=0]
define %struct.NSString* @"-[XCStringList stringRepresentation]"(%struct.XCStringList* %self, %struct..0objc_selector* %_cmd) nounwind {
entry:
%0 = load i32* null, align 4 ; <i32> [#uses=1]
%1 = and i32 %0, 16777215 ; <i32> [#uses=1]
%2 = icmp eq i32 %1, 0 ; <i1> [#uses=1]
br i1 %2, label %bb44, label %bb4
bb4: ; preds = %entry
%3 = load %struct._XCStringListNode** null, align 4 ; <%struct._XCStringListNode*> [#uses=2]
%4 = icmp eq %struct._XCStringListNode* %3, null ; <i1> [#uses=1]
%5 = bitcast %struct._XCStringListNode* %3 to i32* ; <i32*> [#uses=1]
br label %bb37.outer
bb6: ; preds = %bb37
br label %bb19
bb19: ; preds = %bb37, %bb6
%.rle = phi i32 [ 0, %bb6 ], [ %10, %bb37 ] ; <i32> [#uses=1]
%bufptr.0.lcssa = phi i8* [ null, %bb6 ], [ null, %bb37 ] ; <i8*> [#uses=2]
%6 = and i32 %.rle, 16777215 ; <i32> [#uses=1]
%7 = icmp eq i32 %6, 0 ; <i1> [#uses=1]
br i1 %7, label %bb25.split, label %bb37
bb25.split: ; preds = %bb19
call void @foo(i8* getelementptr ([1 x i8]* @"\01LC1", i32 0, i32 0)) nounwind nounwind
br label %bb35.outer
bb34: ; preds = %bb35, %bb35, %bb35, %bb35
%8 = getelementptr i8* %bufptr.0.lcssa, i32 %totalLength.0.ph ; <i8*> [#uses=1]
store i8 92, i8* %8, align 1
br label %bb35.outer
bb35.outer: ; preds = %bb34, %bb25.split
%totalLength.0.ph = add i32 0, %totalLength.1.ph ; <i32> [#uses=2]
br label %bb35
bb35: ; preds = %bb35, %bb35.outer
%9 = load i8* null, align 1 ; <i8> [#uses=1]
switch i8 %9, label %bb35 [
i8 0, label %bb37.outer
i8 32, label %bb34
i8 92, label %bb34
i8 34, label %bb34
i8 39, label %bb34
]
bb37.outer: ; preds = %bb35, %bb4
%totalLength.1.ph = phi i32 [ 0, %bb4 ], [ %totalLength.0.ph, %bb35 ] ; <i32> [#uses=1]
%bufptr.1.ph = phi i8* [ null, %bb4 ], [ %bufptr.0.lcssa, %bb35 ] ; <i8*> [#uses=2]
br i1 %4, label %bb39.split, label %bb37
bb37: ; preds = %bb37.outer, %bb19
%10 = load i32* %5, align 4 ; <i32> [#uses=1]
br i1 false, label %bb6, label %bb19
bb39.split: ; preds = %bb37.outer
%11 = bitcast i8* null to %struct.NSString* ; <%struct.NSString*> [#uses=2]
%12 = icmp eq i8* null, %bufptr.1.ph ; <i1> [#uses=1]
br i1 %12, label %bb44, label %bb42
bb42: ; preds = %bb39.split
call void @quux(i8* %bufptr.1.ph) nounwind nounwind
ret %struct.NSString* %11
bb44: ; preds = %bb39.split, %entry
%.0 = phi %struct.NSString* [ bitcast (%struct.__builtin_CFString* @0 to %struct.NSString*), %entry ], [ %11, %bb39.split ] ; <%struct.NSString*> [#uses=1]
ret %struct.NSString* %.0
}
declare void @foo(i8*)
declare void @quux(i8*)