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-rw-r--r--contrib/llvm/lib/Transforms/Scalar/CodeGenPrepare.cpp80
1 files changed, 57 insertions, 23 deletions
diff --git a/contrib/llvm/lib/Transforms/Scalar/CodeGenPrepare.cpp b/contrib/llvm/lib/Transforms/Scalar/CodeGenPrepare.cpp
index a3c426a714e0..123ed0f4f3de 100644
--- a/contrib/llvm/lib/Transforms/Scalar/CodeGenPrepare.cpp
+++ b/contrib/llvm/lib/Transforms/Scalar/CodeGenPrepare.cpp
@@ -27,6 +27,7 @@
#include "llvm/ADT/SmallSet.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/Analysis/Dominators.h"
+#include "llvm/Analysis/DominatorInternals.h"
#include "llvm/Analysis/InstructionSimplify.h"
#include "llvm/Analysis/ProfileInfo.h"
#include "llvm/Assembly/Writer.h"
@@ -37,12 +38,13 @@
#include "llvm/Support/PatternMatch.h"
#include "llvm/Support/ValueHandle.h"
#include "llvm/Support/raw_ostream.h"
-#include "llvm/Target/TargetData.h"
+#include "llvm/DataLayout.h"
#include "llvm/Target/TargetLibraryInfo.h"
#include "llvm/Target/TargetLowering.h"
#include "llvm/Transforms/Utils/AddrModeMatcher.h"
#include "llvm/Transforms/Utils/BasicBlockUtils.h"
#include "llvm/Transforms/Utils/BuildLibCalls.h"
+#include "llvm/Transforms/Utils/BypassSlowDivision.h"
#include "llvm/Transforms/Utils/Local.h"
using namespace llvm;
using namespace llvm::PatternMatch;
@@ -146,9 +148,18 @@ bool CodeGenPrepare::runOnFunction(Function &F) {
TLInfo = &getAnalysis<TargetLibraryInfo>();
DT = getAnalysisIfAvailable<DominatorTree>();
PFI = getAnalysisIfAvailable<ProfileInfo>();
- OptSize = F.hasFnAttr(Attribute::OptimizeForSize);
+ OptSize = F.getFnAttributes().hasAttribute(Attributes::OptimizeForSize);
+
+ /// This optimization identifies DIV instructions that can be
+ /// profitably bypassed and carried out with a shorter, faster divide.
+ if (TLI && TLI->isSlowDivBypassed()) {
+ const DenseMap<unsigned int, unsigned int> &BypassWidths =
+ TLI->getBypassSlowDivWidths();
+ for (Function::iterator I = F.begin(); I != F.end(); I++)
+ EverMadeChange |= bypassSlowDivision(F, I, BypassWidths);
+ }
- // First pass, eliminate blocks that contain only PHI nodes and an
+ // Eliminate blocks that contain only PHI nodes and an
// unconditional branch.
EverMadeChange |= EliminateMostlyEmptyBlocks(F);
@@ -160,7 +171,7 @@ bool CodeGenPrepare::runOnFunction(Function &F) {
bool MadeChange = true;
while (MadeChange) {
MadeChange = false;
- for (Function::iterator I = F.begin(), E = F.end(); I != E; ) {
+ for (Function::iterator I = F.begin(); I != F.end(); ) {
BasicBlock *BB = I++;
MadeChange |= OptimizeBlock(*BB);
}
@@ -215,11 +226,13 @@ bool CodeGenPrepare::EliminateFallThrough(Function &F) {
// edge, just collapse it.
BasicBlock *SinglePred = BB->getSinglePredecessor();
- if (!SinglePred || SinglePred == BB) continue;
+ // Don't merge if BB's address is taken.
+ if (!SinglePred || SinglePred == BB || BB->hasAddressTaken()) continue;
BranchInst *Term = dyn_cast<BranchInst>(SinglePred->getTerminator());
if (Term && !Term->isConditional()) {
Changed = true;
+ DEBUG(dbgs() << "To merge:\n"<< *SinglePred << "\n\n\n");
// Remember if SinglePred was the entry block of the function.
// If so, we will need to move BB back to the entry position.
bool isEntry = SinglePred == &SinglePred->getParent()->getEntryBlock();
@@ -230,7 +243,6 @@ bool CodeGenPrepare::EliminateFallThrough(Function &F) {
// We have erased a block. Update the iterator.
I = BB;
- DEBUG(dbgs() << "Merged:\n"<< *SinglePred << "\n\n\n");
}
}
return Changed;
@@ -610,7 +622,7 @@ bool CodeGenPrepare::OptimizeCallInst(CallInst *CI) {
// happens.
WeakVH IterHandle(CurInstIterator);
- replaceAndRecursivelySimplify(CI, RetVal, TLI ? TLI->getTargetData() : 0,
+ replaceAndRecursivelySimplify(CI, RetVal, TLI ? TLI->getDataLayout() : 0,
TLInfo, ModifiedDT ? 0 : DT);
// If the iterator instruction was recursively deleted, start over at the
@@ -634,8 +646,8 @@ bool CodeGenPrepare::OptimizeCallInst(CallInst *CI) {
// From here on out we're working with named functions.
if (CI->getCalledFunction() == 0) return false;
- // We'll need TargetData from here on out.
- const TargetData *TD = TLI ? TLI->getTargetData() : 0;
+ // We'll need DataLayout from here on out.
+ const DataLayout *TD = TLI ? TLI->getDataLayout() : 0;
if (!TD) return false;
// Lower all default uses of _chk calls. This is very similar
@@ -649,6 +661,7 @@ bool CodeGenPrepare::OptimizeCallInst(CallInst *CI) {
/// DupRetToEnableTailCallOpts - Look for opportunities to duplicate return
/// instructions to the predecessor to enable tail call optimizations. The
/// case it is currently looking for is:
+/// @code
/// bb0:
/// %tmp0 = tail call i32 @f0()
/// br label %return
@@ -661,9 +674,11 @@ bool CodeGenPrepare::OptimizeCallInst(CallInst *CI) {
/// return:
/// %retval = phi i32 [ %tmp0, %bb0 ], [ %tmp1, %bb1 ], [ %tmp2, %bb2 ]
/// ret i32 %retval
+/// @endcode
///
/// =>
///
+/// @code
/// bb0:
/// %tmp0 = tail call i32 @f0()
/// ret i32 %tmp0
@@ -673,7 +688,7 @@ bool CodeGenPrepare::OptimizeCallInst(CallInst *CI) {
/// bb2:
/// %tmp2 = tail call i32 @f2()
/// ret i32 %tmp2
-///
+/// @endcode
bool CodeGenPrepare::DupRetToEnableTailCallOpts(ReturnInst *RI) {
if (!TLI)
return false;
@@ -699,7 +714,8 @@ bool CodeGenPrepare::DupRetToEnableTailCallOpts(ReturnInst *RI) {
// See llvm::isInTailCallPosition().
const Function *F = BB->getParent();
Attributes CallerRetAttr = F->getAttributes().getRetAttributes();
- if ((CallerRetAttr & Attribute::ZExt) || (CallerRetAttr & Attribute::SExt))
+ if (CallerRetAttr.hasAttribute(Attributes::ZExt) ||
+ CallerRetAttr.hasAttribute(Attributes::SExt))
return false;
// Make sure there are no instructions between the PHI and return, or that the
@@ -757,7 +773,10 @@ bool CodeGenPrepare::DupRetToEnableTailCallOpts(ReturnInst *RI) {
// Conservatively require the attributes of the call to match those of the
// return. Ignore noalias because it doesn't affect the call sequence.
Attributes CalleeRetAttr = CS.getAttributes().getRetAttributes();
- if ((CalleeRetAttr ^ CallerRetAttr) & ~Attribute::NoAlias)
+ if (AttrBuilder(CalleeRetAttr).
+ removeAttribute(Attributes::NoAlias) !=
+ AttrBuilder(CallerRetAttr).
+ removeAttribute(Attributes::NoAlias))
continue;
// Make sure the call instruction is followed by an unconditional branch to
@@ -774,7 +793,7 @@ bool CodeGenPrepare::DupRetToEnableTailCallOpts(ReturnInst *RI) {
}
// If we eliminated all predecessors of the block, delete the block now.
- if (Changed && pred_begin(BB) == pred_end(BB))
+ if (Changed && !BB->hasAddressTaken() && pred_begin(BB) == pred_end(BB))
BB->eraseFromParent();
return Changed;
@@ -914,7 +933,7 @@ bool CodeGenPrepare::OptimizeMemoryInst(Instruction *MemoryInst, Value *Addr,
DEBUG(dbgs() << "CGP: SINKING nonlocal addrmode: " << AddrMode << " for "
<< *MemoryInst);
Type *IntPtrTy =
- TLI->getTargetData()->getIntPtrType(AccessTy->getContext());
+ TLI->getDataLayout()->getIntPtrType(AccessTy->getContext());
Value *Result = 0;
@@ -988,7 +1007,7 @@ bool CodeGenPrepare::OptimizeMemoryInst(Instruction *MemoryInst, Value *Addr,
WeakVH IterHandle(CurInstIterator);
BasicBlock *BB = CurInstIterator->getParent();
- RecursivelyDeleteTriviallyDeadInstructions(Repl);
+ RecursivelyDeleteTriviallyDeadInstructions(Repl, TLInfo);
if (IterHandle != CurInstIterator) {
// If the iterator instruction was recursively deleted, start over at the
@@ -1174,17 +1193,32 @@ static bool isFormingBranchFromSelectProfitable(SelectInst *SI) {
}
+/// If we have a SelectInst that will likely profit from branch prediction,
+/// turn it into a branch.
bool CodeGenPrepare::OptimizeSelectInst(SelectInst *SI) {
- // If we have a SelectInst that will likely profit from branch prediction,
- // turn it into a branch.
- if (DisableSelectToBranch || OptSize || !TLI ||
- !TLI->isPredictableSelectExpensive())
- return false;
+ bool VectorCond = !SI->getCondition()->getType()->isIntegerTy(1);
- if (!SI->getCondition()->getType()->isIntegerTy(1) ||
- !isFormingBranchFromSelectProfitable(SI))
+ // Can we convert the 'select' to CF ?
+ if (DisableSelectToBranch || OptSize || !TLI || VectorCond)
return false;
+ TargetLowering::SelectSupportKind SelectKind;
+ if (VectorCond)
+ SelectKind = TargetLowering::VectorMaskSelect;
+ else if (SI->getType()->isVectorTy())
+ SelectKind = TargetLowering::ScalarCondVectorVal;
+ else
+ SelectKind = TargetLowering::ScalarValSelect;
+
+ // Do we have efficient codegen support for this kind of 'selects' ?
+ if (TLI->isSelectSupported(SelectKind)) {
+ // We have efficient codegen support for the select instruction.
+ // Check if it is profitable to keep this 'select'.
+ if (!TLI->isPredictableSelectExpensive() ||
+ !isFormingBranchFromSelectProfitable(SI))
+ return false;
+ }
+
ModifiedDT = true;
// First, we split the block containing the select into 2 blocks.
@@ -1302,7 +1336,7 @@ bool CodeGenPrepare::OptimizeBlock(BasicBlock &BB) {
bool MadeChange = false;
CurInstIterator = BB.begin();
- for (BasicBlock::iterator E = BB.end(); CurInstIterator != E; )
+ while (CurInstIterator != BB.end())
MadeChange |= OptimizeInst(CurInstIterator++);
return MadeChange;
generated by cgit v1.2.3 (git 2.25.1) at 2024-05-09 20:46:07 +0000