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authorStephen Hines <srhines@google.com>2012-09-13 19:09:19 -0700
committerAndroid Git Automerger <android-git-automerger@android.com>2012-09-13 19:09:19 -0700
commit78c041bd883d86c81c42b98f326660277e6d0d9a (patch)
tree52800183ec2d22164b8f396842142c3a8aab912a /lib/Target/Mips/MipsLongBranch.cpp
parent828ded66831c0caaeecd2291a6bfb084f373d0e4 (diff)
parent1c4ad5ef4fab105f0c8af7edd026e00502fb6279 (diff)
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am 1c4ad5ef: Merge branch \'upstream\' into merge-2012_09_10
* commit '1c4ad5ef4fab105f0c8af7edd026e00502fb6279': (446 commits) Revert r163556. Missed updates to tablegen files. Update function names to conform to guidelines. No functional change intended. test/CodeGen/X86/ms-inline-asm.ll: Relax for non-darwin x86 targets. '##InlineAsm' could not be seen in other hosts. [ms-inline asm] Properly emit the asm directives when the AsmPrinterVariant and InlineAsmVariant don't match. Update test case for Release builds. Remove redundant semicolons which are null statements. Disable stack coloring because it makes dragonegg fail bootstrapping. [ms-inline asm] Pass the correct AsmVariant to the PrintAsmOperand() function and update the printOperand() function accordingly. [ms-inline asm] Add support for .att_syntax directive. Enable stack coloring. Don't attempt to use flags from predicated instructions. [Object] Extract Elf_Ehdr. Patch by Hemant Kulkarni! Stack Coloring: Handle the case where END markers come before BEGIN markers properly. Enhance PR11334 fix to support extload from v2f32/v4f32 Add "blocked" heuristic to the Hexagon MI scheduler. Fold multiply by 0 or 1 when in UnsafeFPMath mode in SelectionDAG::getNode(). whitespace Add boolean simplification support from CMOV Fix an assertion failure when optimising a shufflevector incorrectly into concat_vectors, and a followup bug with SelectionDAG::getNode() creating nodes with invalid types. Minor cleanup. No functional change. ...
Diffstat (limited to 'lib/Target/Mips/MipsLongBranch.cpp')
-rw-r--r--lib/Target/Mips/MipsLongBranch.cpp234
1 files changed, 129 insertions, 105 deletions
diff --git a/lib/Target/Mips/MipsLongBranch.cpp b/lib/Target/Mips/MipsLongBranch.cpp
index f78203f..b9dbd52 100644
--- a/lib/Target/Mips/MipsLongBranch.cpp
+++ b/lib/Target/Mips/MipsLongBranch.cpp
@@ -10,6 +10,10 @@
// This pass expands a branch or jump instruction into a long branch if its
// offset is too large to fit into its immediate field.
//
+// FIXME:
+// 1. Fix pc-region jump instructions which cross 256MB segment boundaries.
+// 2. If program has inline assembly statements whose size cannot be
+// determined accurately, load branch target addresses from the GOT.
//===----------------------------------------------------------------------===//
#define DEBUG_TYPE "mips-long-branch"
@@ -48,7 +52,7 @@ namespace {
typedef MachineBasicBlock::reverse_iterator ReverseIter;
struct MBBInfo {
- uint64_t Size;
+ uint64_t Size, Address;
bool HasLongBranch;
MachineInstr *Br;
@@ -61,7 +65,10 @@ namespace {
static char ID;
MipsLongBranch(TargetMachine &tm)
: MachineFunctionPass(ID), TM(tm),
- TII(static_cast<const MipsInstrInfo*>(tm.getInstrInfo())) {}
+ TII(static_cast<const MipsInstrInfo*>(tm.getInstrInfo())),
+ IsPIC(TM.getRelocationModel() == Reloc::PIC_),
+ ABI(TM.getSubtarget<MipsSubtarget>().getTargetABI()),
+ LongBranchSeqSize(!IsPIC ? 2 : (ABI == MipsSubtarget::N64 ? 13 : 9)) {}
virtual const char *getPassName() const {
return "Mips Long Branch";
@@ -81,6 +88,9 @@ namespace {
const MipsInstrInfo *TII;
MachineFunction *MF;
SmallVector<MBBInfo, 16> MBBInfos;
+ bool IsPIC;
+ unsigned ABI;
+ unsigned LongBranchSeqSize;
};
char MipsLongBranch::ID = 0;
@@ -230,12 +240,6 @@ void MipsLongBranch::replaceBranch(MachineBasicBlock &MBB, Iter Br,
// Expand branch instructions to long branches.
void MipsLongBranch::expandToLongBranch(MBBInfo &I) {
- I.HasLongBranch = true;
-
- bool IsPIC = TM.getRelocationModel() == Reloc::PIC_;
- unsigned ABI = TM.getSubtarget<MipsSubtarget>().getTargetABI();
- bool N64 = ABI == MipsSubtarget::N64;
-
MachineBasicBlock::iterator Pos;
MachineBasicBlock *MBB = I.Br->getParent(), *TgtMBB = getTargetMBB(*I.Br);
DebugLoc DL = I.Br->getDebugLoc();
@@ -248,101 +252,105 @@ void MipsLongBranch::expandToLongBranch(MBBInfo &I) {
MBB->addSuccessor(LongBrMBB);
if (IsPIC) {
- // $longbr:
- // addiu $sp, $sp, -regsize * 2
- // sw $ra, 0($sp)
- // bal $baltgt
- // sw $a3, regsize($sp)
- // $baltgt:
- // lui $a3, %hi($baltgt)
- // lui $at, %hi($tgt)
- // addiu $a3, $a3, %lo($baltgt)
- // addiu $at, $at, %lo($tgt)
- // subu $at, $at, $a3
- // addu $at, $ra, $at
- //
- // if n64:
- // lui $a3, %highest($baltgt)
- // lui $ra, %highest($tgt)
- // addiu $a3, $a3, %higher($baltgt)
- // addiu $ra, $ra, %higher($tgt)
- // dsll $a3, $a3, 32
- // dsll $ra, $ra, 32
- // subu $at, $at, $a3
- // addu $at, $at, $ra
- //
- // lw $ra, 0($sp)
- // lw $a3, regsize($sp)
- // jr $at
- // addiu $sp, $sp, regsize * 2
- // $fallthrough:
- //
- MF->getInfo<MipsFunctionInfo>()->setEmitNOAT();
MachineBasicBlock *BalTgtMBB = MF->CreateMachineBasicBlock(BB);
MF->insert(FallThroughMBB, BalTgtMBB);
LongBrMBB->addSuccessor(BalTgtMBB);
BalTgtMBB->addSuccessor(TgtMBB);
- int RegSize = N64 ? 8 : 4;
- unsigned AT = N64 ? Mips::AT_64 : Mips::AT;
- unsigned A3 = N64 ? Mips::A3_64 : Mips::A3;
- unsigned SP = N64 ? Mips::SP_64 : Mips::SP;
- unsigned RA = N64 ? Mips::RA_64 : Mips::RA;
- unsigned Load = N64 ? Mips::LD_P8 : Mips::LW;
- unsigned Store = N64 ? Mips::SD_P8 : Mips::SW;
- unsigned LUi = N64 ? Mips::LUi64 : Mips::LUi;
- unsigned ADDiu = N64 ? Mips::DADDiu : Mips::ADDiu;
- unsigned ADDu = N64 ? Mips::DADDu : Mips::ADDu;
- unsigned SUBu = N64 ? Mips::SUBu : Mips::SUBu;
- unsigned JR = N64 ? Mips::JR64 : Mips::JR;
-
- Pos = LongBrMBB->begin();
-
- BuildMI(*LongBrMBB, Pos, DL, TII->get(ADDiu), SP).addReg(SP)
- .addImm(-RegSize * 2);
- BuildMI(*LongBrMBB, Pos, DL, TII->get(Store)).addReg(RA).addReg(SP)
- .addImm(0);
- BuildMI(*LongBrMBB, Pos, DL, TII->get(Mips::BAL_BR)).addMBB(BalTgtMBB);
- BuildMI(*LongBrMBB, Pos, DL, TII->get(Store)).addReg(A3).addReg(SP)
- .addImm(RegSize)->setIsInsideBundle();
-
- Pos = BalTgtMBB->begin();
-
- BuildMI(*BalTgtMBB, Pos, DL, TII->get(LUi), A3)
- .addMBB(BalTgtMBB, MipsII::MO_ABS_HI);
- BuildMI(*BalTgtMBB, Pos, DL, TII->get(LUi), AT)
- .addMBB(TgtMBB, MipsII::MO_ABS_HI);
- BuildMI(*BalTgtMBB, Pos, DL, TII->get(ADDiu), A3).addReg(A3)
- .addMBB(BalTgtMBB, MipsII::MO_ABS_LO);
- BuildMI(*BalTgtMBB, Pos, DL, TII->get(ADDiu), AT).addReg(AT)
- .addMBB(TgtMBB, MipsII::MO_ABS_LO);
- BuildMI(*BalTgtMBB, Pos, DL, TII->get(SUBu), AT).addReg(AT).addReg(A3);
- BuildMI(*BalTgtMBB, Pos, DL, TII->get(ADDu), AT).addReg(RA).addReg(AT);
-
- if (N64) {
- BuildMI(*BalTgtMBB, Pos, DL, TII->get(LUi), A3)
- .addMBB(BalTgtMBB, MipsII::MO_HIGHEST);
- BuildMI(*BalTgtMBB, Pos, DL, TII->get(LUi), RA)
- .addMBB(TgtMBB, MipsII::MO_HIGHEST);
- BuildMI(*BalTgtMBB, Pos, DL, TII->get(ADDiu), A3).addReg(A3)
- .addMBB(BalTgtMBB, MipsII::MO_HIGHER);
- BuildMI(*BalTgtMBB, Pos, DL, TII->get(ADDiu), RA).addReg(RA)
- .addMBB(TgtMBB, MipsII::MO_HIGHER);
- BuildMI(*BalTgtMBB, Pos, DL, TII->get(Mips::DSLL), A3).addReg(A3)
- .addImm(32);
- BuildMI(*BalTgtMBB, Pos, DL, TII->get(Mips::DSLL), RA).addReg(RA)
- .addImm(32);
- BuildMI(*BalTgtMBB, Pos, DL, TII->get(SUBu), AT).addReg(AT).addReg(A3);
- BuildMI(*BalTgtMBB, Pos, DL, TII->get(ADDu), AT).addReg(AT).addReg(RA);
- I.Size += 4 * 8;
+ int64_t TgtAddress = MBBInfos[TgtMBB->getNumber()].Address;
+ int64_t Offset = TgtAddress - (I.Address + I.Size - 20);
+ int64_t Lo = SignExtend64<16>(Offset & 0xffff);
+ int64_t Hi = SignExtend64<16>(((Offset + 0x8000) >> 16) & 0xffff);
+
+ if (ABI != MipsSubtarget::N64) {
+ // $longbr:
+ // addiu $sp, $sp, -8
+ // sw $ra, 0($sp)
+ // bal $baltgt
+ // lui $at, %hi($tgt - $baltgt)
+ // $baltgt:
+ // addiu $at, $at, %lo($tgt - $baltgt)
+ // addu $at, $ra, $at
+ // lw $ra, 0($sp)
+ // jr $at
+ // addiu $sp, $sp, 8
+ // $fallthrough:
+ //
+
+ Pos = LongBrMBB->begin();
+
+ BuildMI(*LongBrMBB, Pos, DL, TII->get(Mips::ADDiu), Mips::SP)
+ .addReg(Mips::SP).addImm(-8);
+ BuildMI(*LongBrMBB, Pos, DL, TII->get(Mips::SW)).addReg(Mips::RA)
+ .addReg(Mips::SP).addImm(0);
+ BuildMI(*LongBrMBB, Pos, DL, TII->get(Mips::BAL_BR)).addMBB(BalTgtMBB);
+ BuildMI(*LongBrMBB, Pos, DL, TII->get(Mips::LUi), Mips::AT).addImm(Hi)
+ ->setIsInsideBundle();
+
+ Pos = BalTgtMBB->begin();
+
+ BuildMI(*BalTgtMBB, Pos, DL, TII->get(Mips::ADDiu), Mips::AT)
+ .addReg(Mips::AT).addImm(Lo);
+ BuildMI(*BalTgtMBB, Pos, DL, TII->get(Mips::ADDu), Mips::AT)
+ .addReg(Mips::RA).addReg(Mips::AT);
+ BuildMI(*BalTgtMBB, Pos, DL, TII->get(Mips::LW), Mips::RA)
+ .addReg(Mips::SP).addImm(0);
+ BuildMI(*BalTgtMBB, Pos, DL, TII->get(Mips::JR)).addReg(Mips::AT);
+ BuildMI(*BalTgtMBB, Pos, DL, TII->get(Mips::ADDiu), Mips::SP)
+ .addReg(Mips::SP).addImm(8)->setIsInsideBundle();
+ } else {
+ // $longbr:
+ // daddiu $sp, $sp, -16
+ // sd $ra, 0($sp)
+ // lui64 $at, %highest($tgt - $baltgt)
+ // daddiu $at, $at, %higher($tgt - $baltgt)
+ // dsll $at, $at, 16
+ // daddiu $at, $at, %hi($tgt - $baltgt)
+ // bal $baltgt
+ // dsll $at, $at, 16
+ // $baltgt:
+ // daddiu $at, $at, %lo($tgt - $baltgt)
+ // daddu $at, $ra, $at
+ // ld $ra, 0($sp)
+ // jr64 $at
+ // daddiu $sp, $sp, 16
+ // $fallthrough:
+ //
+
+ int64_t Higher = SignExtend64<16>(((Offset + 0x80008000) >> 32) & 0xffff);
+ int64_t Highest =
+ SignExtend64<16>(((Offset + 0x800080008000LL) >> 48) & 0xffff);
+
+ Pos = LongBrMBB->begin();
+
+ BuildMI(*LongBrMBB, Pos, DL, TII->get(Mips::DADDiu), Mips::SP_64)
+ .addReg(Mips::SP_64).addImm(-16);
+ BuildMI(*LongBrMBB, Pos, DL, TII->get(Mips::SD)).addReg(Mips::RA_64)
+ .addReg(Mips::SP_64).addImm(0);
+ BuildMI(*LongBrMBB, Pos, DL, TII->get(Mips::LUi64), Mips::AT_64)
+ .addImm(Highest);
+ BuildMI(*LongBrMBB, Pos, DL, TII->get(Mips::DADDiu), Mips::AT_64)
+ .addReg(Mips::AT_64).addImm(Higher);
+ BuildMI(*LongBrMBB, Pos, DL, TII->get(Mips::DSLL), Mips::AT_64)
+ .addReg(Mips::AT_64).addImm(16);
+ BuildMI(*LongBrMBB, Pos, DL, TII->get(Mips::DADDiu), Mips::AT_64)
+ .addReg(Mips::AT_64).addImm(Hi);
+ BuildMI(*LongBrMBB, Pos, DL, TII->get(Mips::BAL_BR)).addMBB(BalTgtMBB);
+ BuildMI(*LongBrMBB, Pos, DL, TII->get(Mips::DSLL), Mips::AT_64)
+ .addReg(Mips::AT_64).addImm(16)->setIsInsideBundle();
+
+ Pos = BalTgtMBB->begin();
+
+ BuildMI(*BalTgtMBB, Pos, DL, TII->get(Mips::DADDiu), Mips::AT_64)
+ .addReg(Mips::AT_64).addImm(Lo);
+ BuildMI(*BalTgtMBB, Pos, DL, TII->get(Mips::DADDu), Mips::AT_64)
+ .addReg(Mips::RA_64).addReg(Mips::AT_64);
+ BuildMI(*BalTgtMBB, Pos, DL, TII->get(Mips::LD), Mips::RA_64)
+ .addReg(Mips::SP_64).addImm(0);
+ BuildMI(*BalTgtMBB, Pos, DL, TII->get(Mips::JR64)).addReg(Mips::AT_64);
+ BuildMI(*BalTgtMBB, Pos, DL, TII->get(Mips::DADDiu), Mips::SP_64)
+ .addReg(Mips::SP_64).addImm(16)->setIsInsideBundle();
}
-
- BuildMI(*BalTgtMBB, Pos, DL, TII->get(Load), RA).addReg(SP).addImm(0);
- BuildMI(*BalTgtMBB, Pos, DL, TII->get(Load), A3).addReg(SP).addImm(RegSize);
- BuildMI(*BalTgtMBB, Pos, DL, TII->get(JR)).addReg(AT);
- BuildMI(*BalTgtMBB, Pos, DL, TII->get(ADDiu), SP).addReg(SP)
- .addImm(RegSize * 2)->setIsInsideBundle();
- I.Size += 4 * 14;
} else {
// $longbr:
// j $tgt
@@ -353,7 +361,6 @@ void MipsLongBranch::expandToLongBranch(MBBInfo &I) {
LongBrMBB->addSuccessor(TgtMBB);
BuildMI(*LongBrMBB, Pos, DL, TII->get(Mips::J)).addMBB(TgtMBB);
BuildMI(*LongBrMBB, Pos, DL, TII->get(Mips::NOP))->setIsInsideBundle();
- I.Size += 4 * 2;
}
if (I.Br->isUnconditionalBranch()) {
@@ -401,19 +408,36 @@ bool MipsLongBranch::runOnMachineFunction(MachineFunction &F) {
if (!I->Br || I->HasLongBranch)
continue;
- if (!ForceLongBranch)
- // Check if offset fits into 16-bit immediate field of branches.
- if (isInt<16>(computeOffset(I->Br) / 4))
- continue;
+ // Check if offset fits into 16-bit immediate field of branches.
+ if (!ForceLongBranch && isInt<16>(computeOffset(I->Br) / 4))
+ continue;
- expandToLongBranch(*I);
+ I->HasLongBranch = true;
+ I->Size += LongBranchSeqSize * 4;
++LongBranches;
EverMadeChange = MadeChange = true;
}
}
- if (EverMadeChange)
- MF->RenumberBlocks();
+ if (!EverMadeChange)
+ return true;
+
+ // Compute basic block addresses.
+ if (TM.getRelocationModel() == Reloc::PIC_) {
+ MF->getInfo<MipsFunctionInfo>()->setEmitNOAT();
+
+ uint64_t Address = 0;
+
+ for (I = MBBInfos.begin(); I != E; Address += I->Size, ++I)
+ I->Address = Address;
+ }
+
+ // Do the expansion.
+ for (I = MBBInfos.begin(); I != E; ++I)
+ if (I->HasLongBranch)
+ expandToLongBranch(*I);
+
+ MF->RenumberBlocks();
return true;
}