Add a target callback for FastISel.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@55512 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/llvm/CodeGen/FastISel.h b/include/llvm/CodeGen/FastISel.h
index 20a923b..364f82e 100644
--- a/include/llvm/CodeGen/FastISel.h
+++ b/include/llvm/CodeGen/FastISel.h
@@ -52,10 +52,21 @@
/// the generated MachineInstrs.
BasicBlock::iterator
SelectInstructions(BasicBlock::iterator Begin, BasicBlock::iterator End,
- DenseMap<const Value*, unsigned> &ValueMap,
- DenseMap<const BasicBlock*, MachineBasicBlock *> &MBBMap,
+ DenseMap<const Value *, unsigned> &ValueMap,
+ DenseMap<const BasicBlock *, MachineBasicBlock *> &MBBMap,
MachineBasicBlock *MBB);
+ /// TargetSelectInstruction - This method is called by target-independent
+ /// code when the normal FastISel process fails to select an instruction.
+ /// This gives targets a chance to emit code for anything that doesn't
+ /// fit into FastISel's framework. It returns true if it was successful.
+ ///
+ virtual bool
+ TargetSelectInstruction(Instruction *I,
+ DenseMap<const Value *, unsigned> &ValueMap,
+ DenseMap<const BasicBlock *, MachineBasicBlock *> &MBBMap,
+ MachineBasicBlock *MBB) = 0;
+
virtual ~FastISel();
protected:
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp b/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
index f2246ca..9b982f4 100644
--- a/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
+++ b/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
@@ -5757,10 +5757,15 @@
Begin = F->SelectInstructions(Begin, End, FuncInfo->ValueMap,
FuncInfo->MBBMap, BB);
+ // If the "fast" selector selected the entire block, we're done.
if (Begin == End)
- // The "fast" selector selected the entire block, so we're done.
break;
+ // Next, try calling the target to attempt to handle the instruction.
+ if (F->TargetSelectInstruction(Begin, FuncInfo->ValueMap,
+ FuncInfo->MBBMap, BB))
+ continue;
+
// Handle certain instructions as single-LLVM-Instruction blocks.
if (isa<CallInst>(Begin) || isa<LoadInst>(Begin) ||
isa<StoreInst>(Begin)) {
@@ -5783,7 +5788,7 @@
// The "fast" selector couldn't handle something and bailed.
// For the purpose of debugging, just abort.
#ifndef NDEBUG
- Begin->dump();
+ Begin->dump();
#endif
assert(0 && "FastISel didn't select the entire block");
}
diff --git a/lib/Target/X86/X86FastISel.cpp b/lib/Target/X86/X86FastISel.cpp
index f049a4d..96bdb50 100644
--- a/lib/Target/X86/X86FastISel.cpp
+++ b/lib/Target/X86/X86FastISel.cpp
@@ -19,3 +19,23 @@
#include "X86FastISel.h"
#include "X86TargetMachine.h"
#include "X86GenFastISel.inc"
+
+namespace llvm {
+
+namespace X86 {
+
+bool
+FastISel::TargetSelectInstruction(Instruction *I,
+ DenseMap<const Value *, unsigned> &ValueMap,
+ DenseMap<const BasicBlock *, MachineBasicBlock *> &MBBMap,
+ MachineBasicBlock *MBB) {
+ switch (I->getOpcode()) {
+ default: break;
+ }
+
+ return false;
+}
+
+}
+
+}
diff --git a/utils/TableGen/FastISelEmitter.cpp b/utils/TableGen/FastISelEmitter.cpp
index 305158f..fedb44e 100644
--- a/utils/TableGen/FastISelEmitter.cpp
+++ b/utils/TableGen/FastISelEmitter.cpp
@@ -351,6 +351,14 @@
}
OS << "\n";
+ OS << "bool TargetSelectInstruction(Instruction *I,\n";
+ OS << " "
+ "DenseMap<const Value *, unsigned> &ValueMap,\n";
+ OS << " "
+ "DenseMap<const BasicBlock *, MachineBasicBlock *> &MBBMap,\n";
+ OS << " "
+ "MachineBasicBlock *MBB);\n";
+
// Declare the Subtarget member, which is used for predicate checks.
OS << " const " << InstNS.substr(0, InstNS.size() - 2)
<< "Subtarget *Subtarget;\n";