[llvm-commits] [llvm] r121207 - in /llvm/trunk: include/llvm/MC/MCAsmLayout.h include/llvm/MC/MCAssembler.h lib/MC/MCAssembler.cpp
Rafael Espindola
rafael.espindola at gmail.com
Tue Dec 7 15:32:26 PST 2010
Author: rafael
Date: Tue Dec 7 17:32:26 2010
New Revision: 121207
URL: http://llvm.org/viewvc/llvm-project?rev=121207&view=rev
Log:
Layout each section independently. With the testcase in PR8711:
before:
4 assembler - Number of assembler layout and relaxation steps
78563 assembler - Number of emitted assembler fragments
8693904 assembler - Number of emitted object file bytes
271223 assembler - Number of evaluated fixups
330771677 assembler - Number of fragment layouts
5958 assembler - Number of relaxed instructions
2508361 mcexpr - Number of MCExpr evaluations
real 0m26.123s
user 0m25.694s
sys 0m0.388s
after:
4 assembler - Number of assembler layout and relaxation steps
78563 assembler - Number of emitted assembler fragments
8693904 assembler - Number of emitted object file bytes
271223 assembler - Number of evaluated fixups
231507 assembler - Number of fragment layouts
5958 assembler - Number of relaxed instructions
2508361 mcexpr - Number of MCExpr evaluations
real 0m2.500s
user 0m2.113s
sys 0m0.273s
And yes, the outputs are identical :-)
Modified:
llvm/trunk/include/llvm/MC/MCAsmLayout.h
llvm/trunk/include/llvm/MC/MCAssembler.h
llvm/trunk/lib/MC/MCAssembler.cpp
Modified: llvm/trunk/include/llvm/MC/MCAsmLayout.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/MC/MCAsmLayout.h?rev=121207&r1=121206&r2=121207&view=diff
==============================================================================
--- llvm/trunk/include/llvm/MC/MCAsmLayout.h (original)
+++ llvm/trunk/include/llvm/MC/MCAsmLayout.h Tue Dec 7 17:32:26 2010
@@ -39,13 +39,12 @@
/// The last fragment which was layed out, or 0 if nothing has been layed
/// out. Fragments are always layed out in order, so all fragments with a
/// lower ordinal will be up to date.
- mutable MCFragment *LastValidFragment;
+ mutable DenseMap<const MCSectionData*, MCFragment *> LastValidFragment;
/// \brief Make sure that the layout for the given fragment is valid, lazily
/// computing it if necessary.
void EnsureValid(const MCFragment *F) const;
- bool isSectionUpToDate(const MCSectionData *SD) const;
bool isFragmentUpToDate(const MCFragment *F) const;
public:
@@ -58,9 +57,6 @@
/// fragments size should have already been updated.
void Invalidate(MCFragment *F);
- /// \brief Perform a full layout.
- void LayoutFile();
-
/// \brief Perform layout for a single fragment, assuming that the previous
/// fragment has already been layed out correctly, and the parent section has
/// been initialized.
Modified: llvm/trunk/include/llvm/MC/MCAssembler.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/MC/MCAssembler.h?rev=121207&r1=121206&r2=121207&view=diff
==============================================================================
--- llvm/trunk/include/llvm/MC/MCAssembler.h (original)
+++ llvm/trunk/include/llvm/MC/MCAssembler.h Tue Dec 7 17:32:26 2010
@@ -78,8 +78,7 @@
/// initialized.
uint64_t EffectiveSize;
- /// LayoutOrder - The global layout order of this fragment. This is the index
- /// across all fragments in the file, not just within the section.
+ /// LayoutOrder - The layout order of this fragment.
unsigned LayoutOrder;
/// @}
Modified: llvm/trunk/lib/MC/MCAssembler.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/MC/MCAssembler.cpp?rev=121207&r1=121206&r2=121207&view=diff
==============================================================================
--- llvm/trunk/lib/MC/MCAssembler.cpp (original)
+++ llvm/trunk/lib/MC/MCAssembler.cpp Tue Dec 7 17:32:26 2010
@@ -49,7 +49,7 @@
/* *** */
MCAsmLayout::MCAsmLayout(MCAssembler &Asm)
- : Assembler(Asm), LastValidFragment(0)
+ : Assembler(Asm), LastValidFragment()
{
// Compute the section layout order. Virtual sections must go last.
for (MCAssembler::iterator it = Asm.begin(), ie = Asm.end(); it != ie; ++it)
@@ -60,21 +60,13 @@
SectionOrder.push_back(&*it);
}
-bool MCAsmLayout::isSectionUpToDate(const MCSectionData *SD) const {
- // The first section is always up-to-date.
- unsigned Index = SD->getLayoutOrder();
- if (!Index)
- return true;
-
- // Otherwise, sections are always implicitly computed when the preceeding
- // fragment is layed out.
- const MCSectionData *Prev = getSectionOrder()[Index - 1];
- return isFragmentUpToDate(&(Prev->getFragmentList().back()));
-}
-
bool MCAsmLayout::isFragmentUpToDate(const MCFragment *F) const {
- return (LastValidFragment &&
- F->getLayoutOrder() <= LastValidFragment->getLayoutOrder());
+ const MCSectionData &SD = *F->getParent();
+ const MCFragment *LastValid = LastValidFragment.lookup(&SD);
+ if (!LastValid)
+ return false;
+ assert(LastValid->getParent() == F->getParent());
+ return F->getLayoutOrder() <= LastValid->getLayoutOrder();
}
void MCAsmLayout::Invalidate(MCFragment *F) {
@@ -84,31 +76,23 @@
// Otherwise, reset the last valid fragment to the predecessor of the
// invalidated fragment.
- LastValidFragment = F->getPrevNode();
- if (!LastValidFragment) {
- unsigned Index = F->getParent()->getLayoutOrder();
- if (Index != 0) {
- MCSectionData *Prev = getSectionOrder()[Index - 1];
- LastValidFragment = &(Prev->getFragmentList().back());
- }
- }
+ const MCSectionData &SD = *F->getParent();
+ LastValidFragment[&SD] = F->getPrevNode();
}
void MCAsmLayout::EnsureValid(const MCFragment *F) const {
+ MCSectionData &SD = *F->getParent();
+
+ MCFragment *Cur = LastValidFragment[&SD];
+ if (!Cur)
+ Cur = &*SD.begin();
+ else
+ Cur = Cur->getNextNode();
+
// Advance the layout position until the fragment is up-to-date.
while (!isFragmentUpToDate(F)) {
- // Advance to the next fragment.
- MCFragment *Cur = LastValidFragment;
- if (Cur)
- Cur = Cur->getNextNode();
- if (!Cur) {
- unsigned NextIndex = 0;
- if (LastValidFragment)
- NextIndex = LastValidFragment->getParent()->getLayoutOrder() + 1;
- Cur = SectionOrder[NextIndex]->begin();
- }
-
const_cast<MCAsmLayout*>(this)->LayoutFragment(Cur);
+ Cur = Cur->getNextNode();
}
}
@@ -311,21 +295,11 @@
return 0;
}
-void MCAsmLayout::LayoutFile() {
- // Initialize the first section and set the valid fragment layout point. All
- // actual layout computations are done lazily.
- LastValidFragment = 0;
-}
-
void MCAsmLayout::LayoutFragment(MCFragment *F) {
MCFragment *Prev = F->getPrevNode();
// We should never try to recompute something which is up-to-date.
assert(!isFragmentUpToDate(F) && "Attempt to recompute up-to-date fragment!");
- // We should never try to compute the fragment layout if the section isn't
- // up-to-date.
- assert(isSectionUpToDate(F->getParent()) &&
- "Attempt to compute fragment before it's section!");
// We should never try to compute the fragment layout if it's predecessor
// isn't up-to-date.
assert((!Prev || isFragmentUpToDate(Prev)) &&
@@ -340,7 +314,7 @@
F->Offset = Offset;
F->EffectiveSize = getAssembler().ComputeFragmentSize(*F, F->Offset);
- LastValidFragment = F;
+ LastValidFragment[F->getParent()] = F;
}
/// WriteFragmentData - Write the \arg F data to the output file.
@@ -541,11 +515,11 @@
}
// Assign layout order indices to sections and fragments.
- unsigned FragmentIndex = 0;
for (unsigned i = 0, e = Layout.getSectionOrder().size(); i != e; ++i) {
MCSectionData *SD = Layout.getSectionOrder()[i];
SD->setLayoutOrder(i);
+ unsigned FragmentIndex = 0;
for (MCSectionData::iterator it2 = SD->begin(),
ie2 = SD->end(); it2 != ie2; ++it2)
it2->setLayoutOrder(FragmentIndex++);
@@ -743,9 +717,6 @@
MCAsmLayout &Layout) {
++stats::RelaxationSteps;
- // Layout the sections in order.
- Layout.LayoutFile();
-
// Scan for fragments that need relaxation.
bool WasRelaxed = false;
for (iterator it = begin(), ie = end(); it != ie; ++it) {
@@ -784,16 +755,10 @@
}
void MCAssembler::FinishLayout(MCAsmLayout &Layout) {
- // Lower out any instruction fragments, to simplify the fixup application and
- // output.
- //
- // FIXME-PERF: We don't have to do this, but the assumption is that it is
- // cheap (we will mostly end up eliminating fragments and appending on to data
- // fragments), so the extra complexity downstream isn't worth it. Evaluate
- // this assumption.
-
// The layout is done. Mark every fragment as valid.
- Layout.getFragmentOffset(&*Layout.getSectionOrder().back()->rbegin());
+ for (unsigned int i = 0, n = Layout.getSectionOrder().size(); i != n; ++i) {
+ Layout.getFragmentOffset(&*Layout.getSectionOrder()[i]->rbegin());
+ }
}
// Debugging methods
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