[PowerPC][Future] Initial support for PCRel addressing for constant pool loads

Add initial support for PC Relative addressing for constant pool loads.
This includes adding a new relocation for @pcrel and adding a new PowerPC flag
to identify PC relative addressing.

Differential Revision: https://reviews.llvm.org/D74486
This commit is contained in:
Stefan Pintilie 2020-04-09 11:17:23 -05:00 committed by Kamau Bridgeman
parent 015dee1ac8
commit 75828ef615
18 changed files with 279 additions and 19 deletions

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@ -97,6 +97,7 @@
#undef R_PPC64_DTPREL16_HIGH
#undef R_PPC64_DTPREL16_HIGHA
#undef R_PPC64_REL24_NOTOC
#undef R_PPC64_PCREL34
#undef R_PPC64_IRELATIVE
#undef R_PPC64_REL16
#undef R_PPC64_REL16_LO
@ -192,6 +193,7 @@ ELF_RELOC(R_PPC64_TPREL16_HIGHA, 113)
ELF_RELOC(R_PPC64_DTPREL16_HIGH, 114)
ELF_RELOC(R_PPC64_DTPREL16_HIGHA, 115)
ELF_RELOC(R_PPC64_REL24_NOTOC, 116)
ELF_RELOC(R_PPC64_PCREL34, 132)
ELF_RELOC(R_PPC64_IRELATIVE, 248)
ELF_RELOC(R_PPC64_REL16, 249)
ELF_RELOC(R_PPC64_REL16_LO, 250)

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@ -45,6 +45,8 @@ static uint64_t adjustFixupValue(unsigned Kind, uint64_t Value) {
return Value & 0xffff;
case PPC::fixup_ppc_half16ds:
return Value & 0xfffc;
case PPC::fixup_ppc_pcrel34:
return Value & 0x3ffffffff;
}
}
@ -65,6 +67,7 @@ static unsigned getFixupKindNumBytes(unsigned Kind) {
case PPC::fixup_ppc_br24abs:
case PPC::fixup_ppc_br24_notoc:
return 4;
case PPC::fixup_ppc_pcrel34:
case FK_Data_8:
return 8;
case PPC::fixup_ppc_nofixup:
@ -96,6 +99,7 @@ public:
{ "fixup_ppc_brcond14abs", 16, 14, 0 },
{ "fixup_ppc_half16", 0, 16, 0 },
{ "fixup_ppc_half16ds", 0, 14, 0 },
{ "fixup_ppc_pcrel34", 0, 34, MCFixupKindInfo::FKF_IsPCRel },
{ "fixup_ppc_nofixup", 0, 0, 0 }
};
const static MCFixupKindInfo InfosLE[PPC::NumTargetFixupKinds] = {
@ -107,6 +111,7 @@ public:
{ "fixup_ppc_brcond14abs", 2, 14, 0 },
{ "fixup_ppc_half16", 0, 16, 0 },
{ "fixup_ppc_half16ds", 2, 14, 0 },
{ "fixup_ppc_pcrel34", 0, 34, MCFixupKindInfo::FKF_IsPCRel },
{ "fixup_ppc_nofixup", 0, 0, 0 }
};

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@ -128,6 +128,9 @@ unsigned PPCELFObjectWriter::getRelocType(MCContext &Ctx, const MCValue &Target,
Target.print(errs());
errs() << '\n';
report_fatal_error("Invalid PC-relative half16ds relocation");
case PPC::fixup_ppc_pcrel34:
Type = ELF::R_PPC64_PCREL34;
break;
case FK_Data_4:
case FK_PCRel_4:
Type = ELF::R_PPC_REL32;

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@ -40,6 +40,9 @@ enum Fixups {
/// instrs like 'std'.
fixup_ppc_half16ds,
// A 34-bit fixup corresponding to PC-relative paddi.
fixup_ppc_pcrel34,
/// Not a true fixup, but ties a symbol to a call to __tls_get_addr for the
/// TLS general and local dynamic models, or inserts the thread-pointer
/// register number.

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@ -400,9 +400,13 @@ void PPCInstPrinter::printS16ImmOperand(const MCInst *MI, unsigned OpNo,
void PPCInstPrinter::printS34ImmOperand(const MCInst *MI, unsigned OpNo,
raw_ostream &O) {
long long Value = MI->getOperand(OpNo).getImm();
assert(isInt<34>(Value) && "Invalid s34imm argument!");
O << (long long)Value;
if (MI->getOperand(OpNo).isImm()) {
long long Value = MI->getOperand(OpNo).getImm();
assert(isInt<34>(Value) && "Invalid s34imm argument!");
O << (long long)Value;
}
else
printOperand(MI, OpNo, O);
}
void PPCInstPrinter::printU16ImmOperand(const MCInst *MI, unsigned OpNo,

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@ -104,6 +104,20 @@ unsigned PPCMCCodeEmitter::getImm16Encoding(const MCInst &MI, unsigned OpNo,
return 0;
}
unsigned long
PPCMCCodeEmitter::getImm34Encoding(const MCInst &MI, unsigned OpNo,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const {
const MCOperand &MO = MI.getOperand(OpNo);
if (MO.isReg() || MO.isImm())
return getMachineOpValue(MI, MO, Fixups, STI);
// Add a fixup for the immediate field.
Fixups.push_back(MCFixup::create(IsLittleEndian? 0 : 1, MO.getExpr(),
(MCFixupKind)PPC::fixup_ppc_pcrel34));
return 0;
}
unsigned PPCMCCodeEmitter::getMemRIEncoding(const MCInst &MI, unsigned OpNo,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const {
@ -175,6 +189,16 @@ PPCMCCodeEmitter::getMemRI34PCRelEncoding(const MCInst &MI, unsigned OpNo,
report_fatal_error("Operand must be 0");
const MCOperand &MO = MI.getOperand(OpNo);
if (MO.isExpr()) {
const MCExpr *Expr = MO.getExpr();
const MCSymbolRefExpr *SRE = cast<MCSymbolRefExpr>(Expr);
assert(SRE->getKind() == MCSymbolRefExpr::VK_PCREL &&
"VariantKind must be VK_PCREL");
Fixups.push_back(
MCFixup::create(IsLittleEndian ? 0 : 1, Expr,
static_cast<MCFixupKind>(PPC::fixup_ppc_pcrel34)));
return 0;
}
return ((getMachineOpValue(MI, MO, Fixups, STI)) & 0x3FFFFFFFFUL) | RegBits;
}

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@ -50,6 +50,9 @@ public:
unsigned getImm16Encoding(const MCInst &MI, unsigned OpNo,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
unsigned long getImm34Encoding(const MCInst &MI, unsigned OpNo,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;
unsigned getMemRIEncoding(const MCInst &MI, unsigned OpNo,
SmallVectorImpl<MCFixup> &Fixups,
const MCSubtargetInfo &STI) const;

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@ -98,24 +98,28 @@ namespace llvm {
/// the function's picbase, e.g. lo16(symbol-picbase).
MO_PIC_FLAG = 2,
/// MO_PCREL_FLAG - If this bit is set, the symbol reference is relative to
/// the current instruction address(pc), e.g., var@pcrel. Fixup is VK_PCREL.
MO_PCREL_FLAG = 4,
/// The next are not flags but distinct values.
MO_ACCESS_MASK = 0xf0,
MO_ACCESS_MASK = 0xf00,
/// MO_LO, MO_HA - lo16(symbol) and ha16(symbol)
MO_LO = 1 << 4,
MO_HA = 2 << 4,
MO_LO = 1 << 8,
MO_HA = 2 << 8,
MO_TPREL_LO = 4 << 4,
MO_TPREL_HA = 3 << 4,
MO_TPREL_LO = 4 << 8,
MO_TPREL_HA = 3 << 8,
/// These values identify relocations on immediates folded
/// into memory operations.
MO_DTPREL_LO = 5 << 4,
MO_TLSLD_LO = 6 << 4,
MO_TOC_LO = 7 << 4,
MO_DTPREL_LO = 5 << 8,
MO_TLSLD_LO = 6 << 8,
MO_TOC_LO = 7 << 8,
// Symbol for VK_PPC_TLS fixup attached to an ADD instruction
MO_TLS = 8 << 4
MO_TLS = 8 << 8
};
} // end namespace PPCII

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@ -296,6 +296,10 @@ namespace {
return true;
}
bool SelectAddrPCRel(SDValue N, SDValue &Base) {
return PPCLowering->SelectAddressPCRel(N, Base);
}
/// SelectInlineAsmMemoryOperand - Implement addressing mode selection for
/// inline asm expressions. It is always correct to compute the value into
/// a register. The case of adding a (possibly relocatable) constant to a

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@ -1480,6 +1480,7 @@ const char *PPCTargetLowering::getTargetNodeName(unsigned Opcode) const {
case PPCISD::EXTSWSLI: return "PPCISD::EXTSWSLI";
case PPCISD::LD_VSX_LH: return "PPCISD::LD_VSX_LH";
case PPCISD::FP_EXTEND_HALF: return "PPCISD::FP_EXTEND_HALF";
case PPCISD::MAT_PCREL_ADDR: return "PPCISD::MAT_PCREL_ADDR";
case PPCISD::LD_SPLAT: return "PPCISD::LD_SPLAT";
}
return nullptr;
@ -2346,6 +2347,11 @@ bool PPCTargetLowering::SelectAddressEVXRegReg(SDValue N, SDValue &Base,
bool PPCTargetLowering::SelectAddressRegReg(SDValue N, SDValue &Base,
SDValue &Index, SelectionDAG &DAG,
unsigned EncodingAlignment) const {
// If we have a PC Relative target flag don't select as [reg+reg]. It will be
// a [pc+imm].
if (SelectAddressPCRel(N, Base))
return false;
int16_t imm = 0;
if (N.getOpcode() == ISD::ADD) {
// Is there any SPE load/store (f64), which can't handle 16bit offset?
@ -2435,6 +2441,12 @@ bool PPCTargetLowering::SelectAddressRegImm(SDValue N, SDValue &Disp,
unsigned EncodingAlignment) const {
// FIXME dl should come from parent load or store, not from address
SDLoc dl(N);
// If we have a PC Relative target flag don't select as [reg+imm]. It will be
// a [pc+imm].
if (SelectAddressPCRel(N, Base))
return false;
// If this can be more profitably realized as r+r, fail.
if (SelectAddressRegReg(N, Disp, Base, DAG, EncodingAlignment))
return false;
@ -2558,6 +2570,21 @@ bool PPCTargetLowering::SelectAddressRegRegOnly(SDValue N, SDValue &Base,
return true;
}
/// Returns true if this address is a PC Relative address.
/// PC Relative addresses are marked with the flag PPCII::MO_PCREL_FLAG.
bool PPCTargetLowering::SelectAddressPCRel(SDValue N, SDValue &Base) const {
ConstantPoolSDNode *ConstPoolNode =
dyn_cast<ConstantPoolSDNode>(N.getNode());
bool HasFlag = ConstPoolNode &&
ConstPoolNode->getTargetFlags() == PPCII::MO_PCREL_FLAG;
bool HasNode = N.getOpcode() == PPCISD::MAT_PCREL_ADDR;
if (HasFlag || HasNode) {
Base = N;
return true;
}
return false;
}
/// Returns true if we should use a direct load into vector instruction
/// (such as lxsd or lfd), instead of a load into gpr + direct move sequence.
static bool usePartialVectorLoads(SDNode *N, const PPCSubtarget& ST) {
@ -2763,6 +2790,15 @@ SDValue PPCTargetLowering::LowerConstantPool(SDValue Op,
// 64-bit SVR4 ABI and AIX ABI code are always position-independent.
// The actual address of the GlobalValue is stored in the TOC.
if (Subtarget.is64BitELFABI() || Subtarget.isAIXABI()) {
if (Subtarget.hasPCRelativeMemops()) {
SDLoc DL(CP);
EVT Ty = getPointerTy(DAG.getDataLayout());
SDValue ConstPool = DAG.getTargetConstantPool(C, Ty,
CP->getAlignment(),
CP->getOffset(),
PPCII::MO_PCREL_FLAG);
return DAG.getNode(PPCISD::MAT_PCREL_ADDR, DL, Ty, ConstPool);
}
setUsesTOCBasePtr(DAG);
SDValue GA = DAG.getTargetConstantPool(C, PtrVT, CP->getAlignment(), 0);
return getTOCEntry(DAG, SDLoc(CP), GA);

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@ -428,6 +428,11 @@ namespace llvm {
/// lower (IDX=1) half of v4f32 to v2f64.
FP_EXTEND_HALF,
/// MAT_PCREL_ADDR = Materialize a PC Relative address. This can be done
/// either through an add like PADDI or through a PC Relative load like
/// PLD.
MAT_PCREL_ADDR,
/// CHAIN = STBRX CHAIN, GPRC, Ptr, Type - This is a
/// byte-swapping store instruction. It byte-swaps the low "Type" bits of
/// the GPRC input, then stores it through Ptr. Type can be either i16 or
@ -730,6 +735,10 @@ namespace llvm {
bool SelectAddressRegRegOnly(SDValue N, SDValue &Base, SDValue &Index,
SelectionDAG &DAG) const;
/// SelectAddressPCRel - Represent the specified address as pc relative to
/// be represented as [pc+imm]
bool SelectAddressPCRel(SDValue N, SDValue &Base) const;
Sched::Preference getSchedulingPreference(SDNode *N) const override;
/// LowerOperation - Provide custom lowering hooks for some operations.

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@ -2046,7 +2046,9 @@ ArrayRef<std::pair<unsigned, const char *>>
PPCInstrInfo::getSerializableBitmaskMachineOperandTargetFlags() const {
using namespace PPCII;
static const std::pair<unsigned, const char *> TargetFlags[] = {
{MO_PLT, "ppc-plt"}, {MO_PIC_FLAG, "ppc-pic"}};
{MO_PLT, "ppc-plt"},
{MO_PIC_FLAG, "ppc-pic"},
{MO_PCREL_FLAG, "ppc-pcrel"}};
return makeArrayRef(TargetFlags);
}

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@ -319,6 +319,9 @@ def SDTDynAreaOp : SDTypeProfile<1, 1, []>;
def PPCdynalloc : SDNode<"PPCISD::DYNALLOC", SDTDynOp, [SDNPHasChain]>;
def PPCdynareaoffset : SDNode<"PPCISD::DYNAREAOFFSET", SDTDynAreaOp, [SDNPHasChain]>;
// PC Relative Specific Nodes
def PPCmatpcreladdr : SDNode<"PPCISD::MAT_PCREL_ADDR", SDTIntUnaryOp, []>;
//===----------------------------------------------------------------------===//
// PowerPC specific transformation functions and pattern fragments.
//
@ -730,6 +733,7 @@ def PPCS34ImmAsmOperand : AsmOperandClass {
}
def s34imm : Operand<i64> {
let PrintMethod = "printS34ImmOperand";
let EncoderMethod = "getImm34Encoding";
let ParserMatchClass = PPCS34ImmAsmOperand;
let DecoderMethod = "decodeSImmOperand<34>";
}
@ -977,6 +981,9 @@ def addr : ComplexPattern<iPTR, 1, "SelectAddr",[], []>;
/// This is just the offset part of iaddr, used for preinc.
def iaddroff : ComplexPattern<iPTR, 1, "SelectAddrImmOffs", [], []>;
// PC Relative Address
def pcreladdr : ComplexPattern<iPTR, 1, "SelectAddrPCRel", [], []>;
//===----------------------------------------------------------------------===//
// PowerPC Instruction Predicate Definitions.
def In32BitMode : Predicate<"!PPCSubTarget->isPPC64()">;

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@ -337,3 +337,43 @@ let Predicates = [PrefixInstrs] in {
}
}
// TODO: We have an added complexity of 500 here. This is only a temporary
// solution to have tablegen consider these patterns first. The way we do
// addressing for PowerPC is complex depending on available D form, X form, or
// aligned D form loads/stores like DS and DQ forms. The prefixed
// instructions in this file also add additional PC Relative loads/stores
// and D form loads/stores with 34 bit immediates. It is very difficult to force
// instruction selection to consistently pick these first without the current
// added complexity. Once pc-relative implementation is complete, a set of
// follow-up patches will address this refactoring and the AddedComplexity will
// be removed.
let Predicates = [PCRelativeMemops], AddedComplexity = 500 in {
// Load f32
def : Pat<(f32 (load (PPCmatpcreladdr pcreladdr:$addr))), (PLFSpc $addr, 0)>;
// Load f64
def : Pat<(f64 (extloadf32 (PPCmatpcreladdr pcreladdr:$addr))),
(COPY_TO_REGCLASS (PLFSpc $addr, 0), VSFRC)>;
def : Pat<(f64 (load (PPCmatpcreladdr pcreladdr:$addr))), (PLFDpc $addr, 0)>;
// Load f128
def : Pat<(f128 (load (PPCmatpcreladdr pcreladdr:$addr))),
(COPY_TO_REGCLASS (PLXVpc $addr, 0), VRRC)>;
// Load v4i32
def : Pat<(v4i32 (load (PPCmatpcreladdr pcreladdr:$addr))), (PLXVpc $addr, 0)>;
// Load v2i64
def : Pat<(v2i64 (load (PPCmatpcreladdr pcreladdr:$addr))), (PLXVpc $addr, 0)>;
// Load v4f32
def : Pat<(v4f32 (load (PPCmatpcreladdr pcreladdr:$addr))), (PLXVpc $addr, 0)>;
// Load v2f64
def : Pat<(v2f64 (load (PPCmatpcreladdr pcreladdr:$addr))), (PLXVpc $addr, 0)>;
// If the PPCmatpcreladdr node is not caught by any other pattern it should be
// caught here and turned into a paddi instruction to materialize the address.
def : Pat<(PPCmatpcreladdr pcreladdr:$addr), (PADDI8pc 0, $addr)>;
}

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@ -78,8 +78,10 @@ static MCOperand GetSymbolRef(const MachineOperand &MO, const MCSymbol *Symbol,
break;
}
if (MO.getTargetFlags() == PPCII::MO_PLT)
if (MO.getTargetFlags() == PPCII::MO_PLT)
RefKind = MCSymbolRefExpr::VK_PLT;
else if (MO.getTargetFlags() == PPCII::MO_PCREL_FLAG)
RefKind = MCSymbolRefExpr::VK_PCREL;
const MachineInstr *MI = MO.getParent();

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@ -0,0 +1,92 @@
; RUN: llc -verify-machineinstrs -mtriple=powerpc64le-unknown-linux-gnu \
; RUN: -mcpu=future -enable-ppc-quad-precision -ppc-asm-full-reg-names \
; RUN: < %s | FileCheck %s
define float @FloatConstantPool() {
; CHECK-LABEL: FloatConstantPool:
; CHECK: # %bb.0: # %entry
; CHECK-NEXT: plfs f1, .LCPI0_0@PCREL(0), 1
entry:
ret float 0x380FFFF840000000
}
define double @DoubleConstantPool() {
; CHECK-LABEL: DoubleConstantPool:
; CHECK: # %bb.0: # %entry
; CHECK-NEXT: plfd f1, .LCPI1_0@PCREL(0), 1
entry:
ret double 2.225070e-308
}
define ppc_fp128 @LongDoubleConstantPool() {
; CHECK-LABEL: LongDoubleConstantPool:
; CHECK: # %bb.0: # %entry
; CHECK-NEXT: plfd f1, .LCPI2_0@PCREL(0), 1
; CHECK-NEXT: plfd f2, .LCPI2_1@PCREL(0), 1
entry:
ret ppc_fp128 0xM03600000DBA876CC800D16974FD9D27B
}
define fp128 @__Float128ConstantPool() {
; CHECK-LABEL: __Float128ConstantPool:
; CHECK: # %bb.0: # %entry
; CHECK-NEXT: plxv vs34, .LCPI3_0@PCREL(0), 1
entry:
ret fp128 0xL00000000000000003C00FFFFC5D02B3A
}
define <16 x i8> @VectorCharConstantPool() {
; CHECK-LABEL: VectorCharConstantPool:
; CHECK: # %bb.0: # %entry
; CHECK-NEXT: plxv vs34, .LCPI4_0@PCREL(0), 1
entry:
ret <16 x i8> <i8 -128, i8 -127, i8 -126, i8 -125, i8 -124, i8 -123, i8 -122, i8 -121, i8 -120, i8 -119, i8 -118, i8 -117, i8 -116, i8 -115, i8 -114, i8 -113>
}
define <8 x i16> @VectorShortConstantPool() {
; CHECK-LABEL: VectorShortConstantPool:
; CHECK: # %bb.0: # %entry
; CHECK-NEXT: plxv vs34, .LCPI5_0@PCREL(0), 1
entry:
ret <8 x i16> <i16 -32768, i16 -32767, i16 -32766, i16 -32765, i16 -32764, i16 -32763, i16 -32762, i16 -32761>
}
define <4 x i32> @VectorIntConstantPool() {
; CHECK-LABEL: VectorIntConstantPool:
; CHECK: # %bb.0: # %entry
; CHECK-NEXT: plxv vs34, .LCPI6_0@PCREL(0), 1
entry:
ret <4 x i32> <i32 -2147483648, i32 -2147483647, i32 -2147483646, i32 -2147483645>
}
define <2 x i64> @VectorLongLongConstantPool() {
; CHECK-LABEL: VectorLongLongConstantPool:
; CHECK: # %bb.0: # %entry
; CHECK-NEXT: plxv vs34, .LCPI7_0@PCREL(0), 1
entry:
ret <2 x i64> <i64 -9223372036854775808, i64 -9223372036854775807>
}
define <1 x i128> @VectorInt128ConstantPool() {
; CHECK-LABEL: VectorInt128ConstantPool:
; CHECK: # %bb.0: # %entry
; CHECK-NEXT: plxv vs34, .LCPI8_0@PCREL(0), 1
entry:
ret <1 x i128> <i128 -27670116110564327424>
}
define <4 x float> @VectorFloatConstantPool() {
; CHECK-LABEL: VectorFloatConstantPool:
; CHECK: # %bb.0: # %entry
; CHECK-NEXT: plxv vs34, .LCPI9_0@PCREL(0), 1
entry:
ret <4 x float> <float 0x380FFFF840000000, float 0x380FFF57C0000000, float 0x3843FFFB20000000, float 0x3843FF96C0000000>
}
define <2 x double> @VectorDoubleConstantPool() {
; CHECK-LABEL: VectorDoubleConstantPool:
; CHECK: # %bb.0: # %entry
; CHECK-NEXT: plxv vs34, .LCPI10_0@PCREL(0), 1
entry:
ret <2 x double> <double 2.225070e-308, double 2.225000e-308>
}

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@ -162,12 +162,9 @@ entry:
define dso_local double @UsesX2AsConstPoolTOC() local_unnamed_addr {
; CHECK-S-LABEL: UsesX2AsConstPoolTOC:
; CHECK-S: addis r2, r12, .TOC.-.Lfunc_gep7@ha
; CHECK-S-NEXT: addi r2, r2, .TOC.-.Lfunc_gep7@l
; CHECK-S: .localentry UsesX2AsConstPoolTOC, .Lfunc_lep7-.Lfunc_gep7
; CHECK-S-NOT: .localentry
; CHECK-S: # %bb.0: # %entry
; CHECK-S-NEXT: addis r3, r2, .LCPI7_0@toc@ha
; CHECK-S-NEXT: lfd f1, .LCPI7_0@toc@l(r3)
; CHECK-S-NEXT: plfd f1, .LCPI7_0@PCREL(0), 1
; CHECK-S-NEXT: blr
entry:
ret double 0x404124A4EBDD334C

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@ -0,0 +1,23 @@
; RUN: llc -verify-machineinstrs -mtriple=powerpc64le-unknown-linux-gnu \
; RUN: -mcpu=future -ppc-asm-full-reg-names -ppc-vsr-nums-as-vr < %s | \
; RUN: FileCheck %s --check-prefix=CHECK-S
; RUN: llc -verify-machineinstrs -mtriple=powerpc64le-unknown-linux-gnu \
; RUN: -mcpu=future -ppc-asm-full-reg-names -ppc-vsr-nums-as-vr \
; RUN: --filetype=obj < %s | \
; RUN: llvm-objdump --mcpu=future -dr - | FileCheck %s --check-prefix=CHECK-O
; Constant Pool Index.
; CHECK-S-LABEL: ConstPool
; CHECK-S: plfd f1, .LCPI0_0@PCREL(0), 1
; CHECK-S: blr
; CHECK-O-LABEL: ConstPool
; CHECK-O: plfd 1, 0(0), 1
; CHECK-O-NEXT: R_PPC64_PCREL34 .rodata.cst8
; CHECK-O: blr
define dso_local double @ConstPool() local_unnamed_addr {
entry:
ret double 0x406ECAB439581062
}