[llvm-commits] [llvm] r121710 - in /llvm/trunk: lib/Target/ARM/ARMAsmBackend.cpp lib/Target/ARM/ARMCodeEmitter.cpp lib/Target/ARM/ARMFixupKinds.h lib/Target/ARM/ARMInstrInfo.td lib/Target/ARM/ARMInstrThumb2.td lib/Target/ARM/ARMMCCodeEmitter.cpp utils/TableGen/EDEmitter.cpp utils/TableGen/X86RecognizableInstr.cpp
Owen Anderson
resistor at mac.com
Mon Dec 13 11:31:11 PST 2010
Author: resistor
Date: Mon Dec 13 13:31:11 2010
New Revision: 121710
URL: http://llvm.org/viewvc/llvm-project?rev=121710&view=rev
Log:
In Thumb2, direct branches can be encoded as either a "short" conditional branch with a null predicate, or
as a "long" direct branch. While the mnemonics are the same, they encode the branch offset differently, and
the Darwin assembler appears to prefer the "long" form for direct branches. Thus, in the name of bitwise
equivalence, provide encoding and fixup support for it.
Modified:
llvm/trunk/lib/Target/ARM/ARMAsmBackend.cpp
llvm/trunk/lib/Target/ARM/ARMCodeEmitter.cpp
llvm/trunk/lib/Target/ARM/ARMFixupKinds.h
llvm/trunk/lib/Target/ARM/ARMInstrInfo.td
llvm/trunk/lib/Target/ARM/ARMInstrThumb2.td
llvm/trunk/lib/Target/ARM/ARMMCCodeEmitter.cpp
llvm/trunk/utils/TableGen/EDEmitter.cpp
llvm/trunk/utils/TableGen/X86RecognizableInstr.cpp
Modified: llvm/trunk/lib/Target/ARM/ARMAsmBackend.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/ARM/ARMAsmBackend.cpp?rev=121710&r1=121709&r2=121710&view=diff
==============================================================================
--- llvm/trunk/lib/Target/ARM/ARMAsmBackend.cpp (original)
+++ llvm/trunk/lib/Target/ARM/ARMAsmBackend.cpp Mon Dec 13 13:31:11 2010
@@ -140,11 +140,32 @@
// These values don't encode the low two bits since they're always zero.
// Offset by 8 just as above.
return 0xffffff & ((Value - 8) >> 2);
- case ARM::fixup_t2_branch: {
+ case ARM::fixup_t2_uncondbranch: {
Value = Value - 4;
Value >>= 1; // Low bit is not encoded.
uint32_t out = 0;
+ bool I = Value & 0x800000;
+ bool J1 = Value & 0x400000;
+ bool J2 = Value & 0x200000;
+ J1 ^= I;
+ J2 ^= I;
+
+ out |= I << 26; // S bit
+ out |= !J1 << 13; // J1 bit
+ out |= !J2 << 11; // J2 bit
+ out |= (Value & 0x1FF800) << 5; // imm6 field
+ out |= (Value & 0x0007FF); // imm11 field
+
+ uint64_t swapped = (out & 0xFFFF0000) >> 16;
+ swapped |= (out & 0x0000FFFF) << 16;
+ return swapped;
+ }
+ case ARM::fixup_t2_condbranch: {
+ Value = Value - 4;
+ Value >>= 1; // Low bit is not encoded.
+
+ uint64_t out = 0;
out |= (Value & 0x80000) << 7; // S bit
out |= (Value & 0x40000) >> 7; // J2 bit
out |= (Value & 0x20000) >> 4; // J1 bit
@@ -332,7 +353,8 @@
case FK_Data_4:
case ARM::fixup_t2_ldst_pcrel_12:
- case ARM::fixup_t2_branch:
+ case ARM::fixup_t2_condbranch:
+ case ARM::fixup_t2_uncondbranch:
case ARM::fixup_t2_pcrel_10:
case ARM::fixup_arm_thumb_bl:
case ARM::fixup_arm_thumb_blx:
Modified: llvm/trunk/lib/Target/ARM/ARMCodeEmitter.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/ARM/ARMCodeEmitter.cpp?rev=121710&r1=121709&r2=121710&view=diff
==============================================================================
--- llvm/trunk/lib/Target/ARM/ARMCodeEmitter.cpp (original)
+++ llvm/trunk/lib/Target/ARM/ARMCodeEmitter.cpp Mon Dec 13 13:31:11 2010
@@ -183,6 +183,8 @@
const { return 0; }
unsigned getBranchTargetOpValue(const MachineInstr &MI, unsigned Op)
const { return 0; }
+ unsigned getUnconditionalBranchTargetOpValue(const MachineInstr &MI,
+ unsigned Op) const { return 0; }
unsigned getCCOutOpValue(const MachineInstr &MI, unsigned Op)
const { return 0; }
unsigned getSOImmOpValue(const MachineInstr &MI, unsigned Op)
Modified: llvm/trunk/lib/Target/ARM/ARMFixupKinds.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/ARM/ARMFixupKinds.h?rev=121710&r1=121709&r2=121710&view=diff
==============================================================================
--- llvm/trunk/lib/Target/ARM/ARMFixupKinds.h (original)
+++ llvm/trunk/lib/Target/ARM/ARMFixupKinds.h Mon Dec 13 13:31:11 2010
@@ -36,9 +36,12 @@
// fixup_arm_branch - 24-bit PC relative relocation for direct branch
// instructions.
fixup_arm_branch,
- // fixup_t2_branch - 20-bit PC relative relocation for Thumb2 direct branch
- // instructions.
- fixup_t2_branch,
+ // fixup_t2_condbranch - 20-bit PC relative relocation for Thumb2 direct
+ // uconditional branch instructions.
+ fixup_t2_condbranch,
+ // fixup_t2_uncondbranch - 20-bit PC relative relocation for Thumb2 direct
+ // branch unconditional branch instructions.
+ fixup_t2_uncondbranch,
// fixup_arm_thumb_br - 12-bit fixup for Thumb B instructions.
fixup_arm_thumb_br,
Modified: llvm/trunk/lib/Target/ARM/ARMInstrInfo.td
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/ARM/ARMInstrInfo.td?rev=121710&r1=121709&r2=121710&view=diff
==============================================================================
--- llvm/trunk/lib/Target/ARM/ARMInstrInfo.td (original)
+++ llvm/trunk/lib/Target/ARM/ARMInstrInfo.td Mon Dec 13 13:31:11 2010
@@ -293,6 +293,10 @@
let EncoderMethod = "getBranchTargetOpValue";
}
+def uncondbrtarget : Operand<OtherVT> {
+ let EncoderMethod = "getUnconditionalBranchTargetOpValue";
+}
+
// Call target.
def bltarget : Operand<i32> {
// Encoded the same as branch targets.
Modified: llvm/trunk/lib/Target/ARM/ARMInstrThumb2.td
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/ARM/ARMInstrThumb2.td?rev=121710&r1=121709&r2=121710&view=diff
==============================================================================
--- llvm/trunk/lib/Target/ARM/ARMInstrThumb2.td (original)
+++ llvm/trunk/lib/Target/ARM/ARMInstrThumb2.td Mon Dec 13 13:31:11 2010
@@ -2961,7 +2961,7 @@
let isBranch = 1, isTerminator = 1, isBarrier = 1 in {
let isPredicable = 1 in
-def t2B : T2XI<(outs), (ins brtarget:$target), IIC_Br,
+def t2B : T2XI<(outs), (ins uncondbrtarget:$target), IIC_Br,
"b.w\t$target",
[(br bb:$target)]> {
let Inst{31-27} = 0b11110;
Modified: llvm/trunk/lib/Target/ARM/ARMMCCodeEmitter.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/ARM/ARMMCCodeEmitter.cpp?rev=121710&r1=121709&r2=121710&view=diff
==============================================================================
--- llvm/trunk/lib/Target/ARM/ARMMCCodeEmitter.cpp (original)
+++ llvm/trunk/lib/Target/ARM/ARMMCCodeEmitter.cpp Mon Dec 13 13:31:11 2010
@@ -57,7 +57,8 @@
MCFixupKindInfo::FKF_IsAligned},
{ "fixup_arm_adr_pcrel_12", 1, 24, MCFixupKindInfo::FKF_IsPCRel },
{ "fixup_arm_branch", 1, 24, MCFixupKindInfo::FKF_IsPCRel },
-{ "fixup_t2_branch", 0, 32, MCFixupKindInfo::FKF_IsPCRel },
+{ "fixup_t2_condbranch", 0, 32, MCFixupKindInfo::FKF_IsPCRel },
+{ "fixup_t2_uncondbranch", 0, 32, MCFixupKindInfo::FKF_IsPCRel },
{ "fixup_arm_thumb_br", 0, 16, MCFixupKindInfo::FKF_IsPCRel },
{ "fixup_arm_thumb_bl", 0, 32, MCFixupKindInfo::FKF_IsPCRel },
{ "fixup_arm_thumb_blx", 7, 21, MCFixupKindInfo::FKF_IsPCRel },
@@ -122,6 +123,12 @@
uint32_t getBranchTargetOpValue(const MCInst &MI, unsigned OpIdx,
SmallVectorImpl<MCFixup> &Fixups) const;
+ /// getUnconditionalBranchTargetOpValue - Return encoding info for 24-bit
+ /// immediate Thumb2 direct branch target.
+ uint32_t getUnconditionalBranchTargetOpValue(const MCInst &MI, unsigned OpIdx,
+ SmallVectorImpl<MCFixup> &Fixups) const;
+
+
/// getAdrLabelOpValue - Return encoding info for 12-bit immediate
/// ADR label target.
uint32_t getAdrLabelOpValue(const MCInst &MI, unsigned OpIdx,
@@ -499,10 +506,34 @@
// coupling between MC and TM anywhere we can help it.
const ARMSubtarget &Subtarget = TM.getSubtarget<ARMSubtarget>();
if (Subtarget.isThumb2())
- return ::getBranchTargetOpValue(MI, OpIdx, ARM::fixup_t2_branch, Fixups);
+ return
+ ::getBranchTargetOpValue(MI, OpIdx, ARM::fixup_t2_condbranch, Fixups);
return ::getBranchTargetOpValue(MI, OpIdx, ARM::fixup_arm_branch, Fixups);
}
+/// getUnconditionalBranchTargetOpValue - Return encoding info for 24-bit
+/// immediate branch target.
+uint32_t ARMMCCodeEmitter::
+getUnconditionalBranchTargetOpValue(const MCInst &MI, unsigned OpIdx,
+ SmallVectorImpl<MCFixup> &Fixups) const {
+ unsigned Val =
+ ::getBranchTargetOpValue(MI, OpIdx, ARM::fixup_t2_uncondbranch, Fixups);
+ bool I = (Val & 0x800000);
+ bool J1 = (Val & 0x400000);
+ bool J2 = (Val & 0x200000);
+ if (I ^ J1)
+ Val &= ~0x400000;
+ else
+ Val |= 0x400000;
+
+ if (I ^ J2)
+ Val &= ~0x200000;
+ else
+ Val |= 0x200000;
+
+ return Val;
+}
+
/// getAdrLabelOpValue - Return encoding info for 12-bit immediate ADR label
/// target.
uint32_t ARMMCCodeEmitter::
Modified: llvm/trunk/utils/TableGen/EDEmitter.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/utils/TableGen/EDEmitter.cpp?rev=121710&r1=121709&r2=121710&view=diff
==============================================================================
--- llvm/trunk/utils/TableGen/EDEmitter.cpp (original)
+++ llvm/trunk/utils/TableGen/EDEmitter.cpp Mon Dec 13 13:31:11 2010
@@ -322,6 +322,7 @@
PCR("offset32");
PCR("offset64");
PCR("brtarget");
+ PCR("uncondbrtarget");
PCR("bltarget");
return 1;
@@ -587,6 +588,7 @@
IMM("neon_vcvt_imm32");
MISC("brtarget", "kOperandTypeARMBranchTarget"); // ?
+ MISC("uncondbrtarget", "kOperandTypeARMBranchTarget"); // ?
MISC("t_brtarget", "kOperandTypeARMBranchTarget"); // ?
MISC("t_bcctarget", "kOperandTypeARMBranchTarget"); // ?
MISC("t_cbtarget", "kOperandTypeARMBranchTarget"); // ?
Modified: llvm/trunk/utils/TableGen/X86RecognizableInstr.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/utils/TableGen/X86RecognizableInstr.cpp?rev=121710&r1=121709&r2=121710&view=diff
==============================================================================
--- llvm/trunk/utils/TableGen/X86RecognizableInstr.cpp (original)
+++ llvm/trunk/utils/TableGen/X86RecognizableInstr.cpp Mon Dec 13 13:31:11 2010
@@ -857,6 +857,7 @@
TYPE("i32imm_pcrel", TYPE_REL32)
TYPE("SSECC", TYPE_IMM3)
TYPE("brtarget", TYPE_RELv)
+ TYPE("uncondbrtarget", TYPE_RELv)
TYPE("brtarget8", TYPE_REL8)
TYPE("f80mem", TYPE_M80FP)
TYPE("lea32mem", TYPE_LEA)
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