Exit with nice warnings when register allocator run out of registers.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@63267 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/RegAllocLocal.cpp b/lib/CodeGen/RegAllocLocal.cpp
index 174e394..9fc5f73 100644
--- a/lib/CodeGen/RegAllocLocal.cpp
+++ b/lib/CodeGen/RegAllocLocal.cpp
@@ -27,6 +27,7 @@
#include "llvm/Support/Compiler.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/IndexedMap.h"
+#include "llvm/ADT/SmallSet.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/ADT/STLExtras.h"
@@ -237,7 +238,7 @@
/// value. This method returns the modified instruction.
///
MachineInstr *reloadVirtReg(MachineBasicBlock &MBB, MachineInstr *MI,
- unsigned OpNum);
+ unsigned OpNum, SmallSet<unsigned, 4> &RRegs);
/// ComputeLocalLiveness - Computes liveness of registers within a basic
/// block, setting the killed/dead flags as appropriate.
@@ -475,7 +476,8 @@
/// modified instruction.
///
MachineInstr *RALocal::reloadVirtReg(MachineBasicBlock &MBB, MachineInstr *MI,
- unsigned OpNum) {
+ unsigned OpNum,
+ SmallSet<unsigned, 4> &ReloadedRegs) {
unsigned VirtReg = MI->getOperand(OpNum).getReg();
// If the virtual register is already available, just update the instruction
@@ -513,6 +515,29 @@
MF->getRegInfo().setPhysRegUsed(PhysReg);
MI->getOperand(OpNum).setReg(PhysReg); // Assign the input register
getVirtRegLastUse(VirtReg) = std::make_pair(MI, OpNum);
+
+ if (!ReloadedRegs.insert(PhysReg)) {
+ cerr << "Ran out of registers during register allocation!\n";
+ if (MI->getOpcode() == TargetInstrInfo::INLINEASM) {
+ cerr << "Please check your inline asm statement for invalid "
+ << "constraints:\n";
+ MI->print(cerr.stream(), TM);
+ }
+ exit(1);
+ }
+ for (const unsigned *SubRegs = TRI->getSubRegisters(PhysReg);
+ *SubRegs; ++SubRegs) {
+ if (!ReloadedRegs.insert(*SubRegs)) {
+ cerr << "Ran out of registers during register allocation!\n";
+ if (MI->getOpcode() == TargetInstrInfo::INLINEASM) {
+ cerr << "Please check your inline asm statement for invalid "
+ << "constraints:\n";
+ MI->print(cerr.stream(), TM);
+ }
+ exit(1);
+ }
+ }
+
return MI;
}
@@ -581,17 +606,16 @@
if (TargetRegisterInfo::isVirtualRegister(MO.getReg())) continue;
- const unsigned* subregs = TRI->getAliasSet(MO.getReg());
- if (subregs) {
- while (*subregs) {
+ const unsigned* Aliases = TRI->getAliasSet(MO.getReg());
+ if (Aliases) {
+ while (*Aliases) {
DenseMap<unsigned, std::pair<MachineInstr*, unsigned> >::iterator
- alias = LastUseDef.find(*subregs);
+ alias = LastUseDef.find(*Aliases);
- if (alias != LastUseDef.end() &&
- alias->second.first != I)
- LastUseDef[*subregs] = std::make_pair(I, i);
+ if (alias != LastUseDef.end() && alias->second.first != I)
+ LastUseDef[*Aliases] = std::make_pair(I, i);
- ++subregs;
+ ++Aliases;
}
}
}
@@ -695,12 +719,12 @@
MF->getRegInfo().setPhysRegUsed(Reg);
PhysRegsUsed[Reg] = 0; // It is free and reserved now
AddToPhysRegsUseOrder(Reg);
- for (const unsigned *AliasSet = TRI->getSubRegisters(Reg);
- *AliasSet; ++AliasSet) {
- if (PhysRegsUsed[*AliasSet] != -2) {
- AddToPhysRegsUseOrder(*AliasSet);
- PhysRegsUsed[*AliasSet] = 0; // It is free and reserved now
- MF->getRegInfo().setPhysRegUsed(*AliasSet);
+ for (const unsigned *SubRegs = TRI->getSubRegisters(Reg);
+ *SubRegs; ++SubRegs) {
+ if (PhysRegsUsed[*SubRegs] != -2) {
+ AddToPhysRegsUseOrder(*SubRegs);
+ PhysRegsUsed[*SubRegs] = 0; // It is free and reserved now
+ MF->getRegInfo().setPhysRegUsed(*SubRegs);
}
}
}
@@ -778,12 +802,12 @@
PhysRegsUsed[Reg] = 0; // It is free and reserved now
AddToPhysRegsUseOrder(Reg);
- for (const unsigned *AliasSet = TRI->getSubRegisters(Reg);
- *AliasSet; ++AliasSet) {
- if (PhysRegsUsed[*AliasSet] != -2) {
- MF->getRegInfo().setPhysRegUsed(*AliasSet);
- PhysRegsUsed[*AliasSet] = 0; // It is free and reserved now
- AddToPhysRegsUseOrder(*AliasSet);
+ for (const unsigned *SubRegs = TRI->getSubRegisters(Reg);
+ *SubRegs; ++SubRegs) {
+ if (PhysRegsUsed[*SubRegs] != -2) {
+ MF->getRegInfo().setPhysRegUsed(*SubRegs);
+ PhysRegsUsed[*SubRegs] = 0; // It is free and reserved now
+ AddToPhysRegsUseOrder(*SubRegs);
}
}
}
@@ -797,12 +821,13 @@
// physical register is referenced by the instruction, that it is guaranteed
// to be live-in, or the input is badly hosed.
//
+ SmallSet<unsigned, 4> ReloadedRegs;
for (unsigned i = 0; i != MI->getNumOperands(); ++i) {
MachineOperand& MO = MI->getOperand(i);
// here we are looking for only used operands (never def&use)
if (MO.isReg() && !MO.isDef() && MO.getReg() && !MO.isImplicit() &&
TargetRegisterInfo::isVirtualRegister(MO.getReg()))
- MI = reloadVirtReg(MBB, MI, i);
+ MI = reloadVirtReg(MBB, MI, i, ReloadedRegs);
}
// If this instruction is the last user of this register, kill the
@@ -830,13 +855,13 @@
DOUT << " Last use of " << TRI->getName(PhysReg)
<< "[%reg" << VirtReg <<"], removing it from live set\n";
removePhysReg(PhysReg);
- for (const unsigned *AliasSet = TRI->getSubRegisters(PhysReg);
- *AliasSet; ++AliasSet) {
- if (PhysRegsUsed[*AliasSet] != -2) {
+ for (const unsigned *SubRegs = TRI->getSubRegisters(PhysReg);
+ *SubRegs; ++SubRegs) {
+ if (PhysRegsUsed[*SubRegs] != -2) {
DOUT << " Last use of "
- << TRI->getName(*AliasSet)
+ << TRI->getName(*SubRegs)
<< "[%reg" << VirtReg <<"], removing it from live set\n";
- removePhysReg(*AliasSet);
+ removePhysReg(*SubRegs);
}
}
}
@@ -861,12 +886,12 @@
PhysRegsUsed[Reg] = 0; // It is free and reserved now
AddToPhysRegsUseOrder(Reg);
- for (const unsigned *AliasSet = TRI->getSubRegisters(Reg);
- *AliasSet; ++AliasSet) {
- if (PhysRegsUsed[*AliasSet] != -2) {
- MF->getRegInfo().setPhysRegUsed(*AliasSet);
- PhysRegsUsed[*AliasSet] = 0; // It is free and reserved now
- AddToPhysRegsUseOrder(*AliasSet);
+ for (const unsigned *SubRegs = TRI->getSubRegisters(Reg);
+ *SubRegs; ++SubRegs) {
+ if (PhysRegsUsed[*SubRegs] != -2) {
+ MF->getRegInfo().setPhysRegUsed(*SubRegs);
+ PhysRegsUsed[*SubRegs] = 0; // It is free and reserved now
+ AddToPhysRegsUseOrder(*SubRegs);
}
}
}
@@ -883,12 +908,12 @@
PhysRegsUsed[Reg] = 0; // It is free and reserved now
}
MF->getRegInfo().setPhysRegUsed(Reg);
- for (const unsigned *AliasSet = TRI->getSubRegisters(Reg);
- *AliasSet; ++AliasSet) {
- if (PhysRegsUsed[*AliasSet] != -2) {
- AddToPhysRegsUseOrder(*AliasSet);
- PhysRegsUsed[*AliasSet] = 0; // It is free and reserved now
- MF->getRegInfo().setPhysRegUsed(*AliasSet);
+ for (const unsigned *SubRegs = TRI->getSubRegisters(Reg);
+ *SubRegs; ++SubRegs) {
+ if (PhysRegsUsed[*SubRegs] != -2) {
+ AddToPhysRegsUseOrder(*SubRegs);
+ PhysRegsUsed[*SubRegs] = 0; // It is free and reserved now
+ MF->getRegInfo().setPhysRegUsed(*SubRegs);
}
}
}