[llvm-commits] [llvm] r164243 - in /llvm/trunk: lib/Target/X86/X86ISelDAGToDAG.cpp test/CodeGen/X86/atomic_add.ll
Michael Liao
michael.liao at intel.com
Wed Sep 19 12:36:59 PDT 2012
Author: hliao
Date: Wed Sep 19 14:36:58 2012
New Revision: 164243
URL: http://llvm.org/viewvc/llvm-project?rev=164243&view=rev
Log:
Unify the logic in SelectAtomicLoadAdd and SelectAtomicLoadArith
- Merge the processing of LOAD_ADD with other atomic load-arith
operations
- Separate the logic getting target constant for atomic-load-op and add
an optimization for atomic-load-add on i16 with negative value
- Optimize a minor case for atomic-fetch-add i16 with negative operand. Test
case is revised.
Modified:
llvm/trunk/lib/Target/X86/X86ISelDAGToDAG.cpp
llvm/trunk/test/CodeGen/X86/atomic_add.ll
Modified: llvm/trunk/lib/Target/X86/X86ISelDAGToDAG.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/X86ISelDAGToDAG.cpp?rev=164243&r1=164242&r2=164243&view=diff
==============================================================================
--- llvm/trunk/lib/Target/X86/X86ISelDAGToDAG.cpp (original)
+++ llvm/trunk/lib/Target/X86/X86ISelDAGToDAG.cpp Wed Sep 19 14:36:58 2012
@@ -191,7 +191,6 @@
SDNode *Select(SDNode *N);
SDNode *SelectGather(SDNode *N, unsigned Opc);
SDNode *SelectAtomic64(SDNode *Node, unsigned Opc);
- SDNode *SelectAtomicLoadAdd(SDNode *Node, EVT NVT);
SDNode *SelectAtomicLoadArith(SDNode *Node, EVT NVT);
bool FoldOffsetIntoAddress(uint64_t Offset, X86ISelAddressMode &AM);
@@ -1480,6 +1479,7 @@
SDValue In1 = Node->getOperand(1);
SDValue In2L = Node->getOperand(2);
SDValue In2H = Node->getOperand(3);
+
SDValue Tmp0, Tmp1, Tmp2, Tmp3, Tmp4;
if (!SelectAddr(Node, In1, Tmp0, Tmp1, Tmp2, Tmp3, Tmp4))
return NULL;
@@ -1493,159 +1493,13 @@
return ResNode;
}
-// FIXME: Figure out some way to unify this with the 'or' and other code
-// below.
-SDNode *X86DAGToDAGISel::SelectAtomicLoadAdd(SDNode *Node, EVT NVT) {
- if (Node->hasAnyUseOfValue(0))
- return 0;
-
- // Optimize common patterns for __sync_add_and_fetch and
- // __sync_sub_and_fetch where the result is not used. This allows us
- // to use "lock" version of add, sub, inc, dec instructions.
- // FIXME: Do not use special instructions but instead add the "lock"
- // prefix to the target node somehow. The extra information will then be
- // transferred to machine instruction and it denotes the prefix.
- SDValue Chain = Node->getOperand(0);
- SDValue Ptr = Node->getOperand(1);
- SDValue Val = Node->getOperand(2);
- SDValue Tmp0, Tmp1, Tmp2, Tmp3, Tmp4;
- if (!SelectAddr(Node, Ptr, Tmp0, Tmp1, Tmp2, Tmp3, Tmp4))
- return 0;
-
- bool isInc = false, isDec = false, isSub = false, isCN = false;
- ConstantSDNode *CN = dyn_cast<ConstantSDNode>(Val);
- if (CN && CN->getSExtValue() == (int32_t)CN->getSExtValue()) {
- isCN = true;
- int64_t CNVal = CN->getSExtValue();
- if (CNVal == 1)
- isInc = true;
- else if (CNVal == -1)
- isDec = true;
- else if (CNVal >= 0)
- Val = CurDAG->getTargetConstant(CNVal, NVT);
- else {
- isSub = true;
- Val = CurDAG->getTargetConstant(-CNVal, NVT);
- }
- } else if (Val.hasOneUse() &&
- Val.getOpcode() == ISD::SUB &&
- X86::isZeroNode(Val.getOperand(0))) {
- isSub = true;
- Val = Val.getOperand(1);
- }
-
- DebugLoc dl = Node->getDebugLoc();
- unsigned Opc = 0;
- switch (NVT.getSimpleVT().SimpleTy) {
- default: return 0;
- case MVT::i8:
- if (isInc)
- Opc = X86::LOCK_INC8m;
- else if (isDec)
- Opc = X86::LOCK_DEC8m;
- else if (isSub) {
- if (isCN)
- Opc = X86::LOCK_SUB8mi;
- else
- Opc = X86::LOCK_SUB8mr;
- } else {
- if (isCN)
- Opc = X86::LOCK_ADD8mi;
- else
- Opc = X86::LOCK_ADD8mr;
- }
- break;
- case MVT::i16:
- if (isInc)
- Opc = X86::LOCK_INC16m;
- else if (isDec)
- Opc = X86::LOCK_DEC16m;
- else if (isSub) {
- if (isCN) {
- if (immSext8(Val.getNode()))
- Opc = X86::LOCK_SUB16mi8;
- else
- Opc = X86::LOCK_SUB16mi;
- } else
- Opc = X86::LOCK_SUB16mr;
- } else {
- if (isCN) {
- if (immSext8(Val.getNode()))
- Opc = X86::LOCK_ADD16mi8;
- else
- Opc = X86::LOCK_ADD16mi;
- } else
- Opc = X86::LOCK_ADD16mr;
- }
- break;
- case MVT::i32:
- if (isInc)
- Opc = X86::LOCK_INC32m;
- else if (isDec)
- Opc = X86::LOCK_DEC32m;
- else if (isSub) {
- if (isCN) {
- if (immSext8(Val.getNode()))
- Opc = X86::LOCK_SUB32mi8;
- else
- Opc = X86::LOCK_SUB32mi;
- } else
- Opc = X86::LOCK_SUB32mr;
- } else {
- if (isCN) {
- if (immSext8(Val.getNode()))
- Opc = X86::LOCK_ADD32mi8;
- else
- Opc = X86::LOCK_ADD32mi;
- } else
- Opc = X86::LOCK_ADD32mr;
- }
- break;
- case MVT::i64:
- if (isInc)
- Opc = X86::LOCK_INC64m;
- else if (isDec)
- Opc = X86::LOCK_DEC64m;
- else if (isSub) {
- Opc = X86::LOCK_SUB64mr;
- if (isCN) {
- if (immSext8(Val.getNode()))
- Opc = X86::LOCK_SUB64mi8;
- else if (i64immSExt32(Val.getNode()))
- Opc = X86::LOCK_SUB64mi32;
- }
- } else {
- Opc = X86::LOCK_ADD64mr;
- if (isCN) {
- if (immSext8(Val.getNode()))
- Opc = X86::LOCK_ADD64mi8;
- else if (i64immSExt32(Val.getNode()))
- Opc = X86::LOCK_ADD64mi32;
- }
- }
- break;
- }
-
- SDValue Undef = SDValue(CurDAG->getMachineNode(TargetOpcode::IMPLICIT_DEF,
- dl, NVT), 0);
- MachineSDNode::mmo_iterator MemOp = MF->allocateMemRefsArray(1);
- MemOp[0] = cast<MemSDNode>(Node)->getMemOperand();
- if (isInc || isDec) {
- SDValue Ops[] = { Tmp0, Tmp1, Tmp2, Tmp3, Tmp4, Chain };
- SDValue Ret = SDValue(CurDAG->getMachineNode(Opc, dl, MVT::Other, Ops, 6), 0);
- cast<MachineSDNode>(Ret)->setMemRefs(MemOp, MemOp + 1);
- SDValue RetVals[] = { Undef, Ret };
- return CurDAG->getMergeValues(RetVals, 2, dl).getNode();
- } else {
- SDValue Ops[] = { Tmp0, Tmp1, Tmp2, Tmp3, Tmp4, Val, Chain };
- SDValue Ret = SDValue(CurDAG->getMachineNode(Opc, dl, MVT::Other, Ops, 7), 0);
- cast<MachineSDNode>(Ret)->setMemRefs(MemOp, MemOp + 1);
- SDValue RetVals[] = { Undef, Ret };
- return CurDAG->getMergeValues(RetVals, 2, dl).getNode();
- }
-}
-
+/// Atomic opcode table
+///
enum AtomicOpc {
+ ADD,
+ SUB,
+ INC,
+ DEC,
OR,
AND,
XOR,
@@ -1669,6 +1523,58 @@
static const uint16_t AtomicOpcTbl[AtomicOpcEnd][AtomicSzEnd] = {
{
+ X86::LOCK_ADD8mi,
+ X86::LOCK_ADD8mr,
+ X86::LOCK_ADD16mi8,
+ X86::LOCK_ADD16mi,
+ X86::LOCK_ADD16mr,
+ X86::LOCK_ADD32mi8,
+ X86::LOCK_ADD32mi,
+ X86::LOCK_ADD32mr,
+ X86::LOCK_ADD64mi8,
+ X86::LOCK_ADD64mi32,
+ X86::LOCK_ADD64mr,
+ },
+ {
+ X86::LOCK_SUB8mi,
+ X86::LOCK_SUB8mr,
+ X86::LOCK_SUB16mi8,
+ X86::LOCK_SUB16mi,
+ X86::LOCK_SUB16mr,
+ X86::LOCK_SUB32mi8,
+ X86::LOCK_SUB32mi,
+ X86::LOCK_SUB32mr,
+ X86::LOCK_SUB64mi8,
+ X86::LOCK_SUB64mi32,
+ X86::LOCK_SUB64mr,
+ },
+ {
+ 0,
+ X86::LOCK_INC8m,
+ 0,
+ 0,
+ X86::LOCK_INC16m,
+ 0,
+ 0,
+ X86::LOCK_INC32m,
+ 0,
+ 0,
+ X86::LOCK_INC64m,
+ },
+ {
+ 0,
+ X86::LOCK_DEC8m,
+ 0,
+ 0,
+ X86::LOCK_DEC16m,
+ 0,
+ 0,
+ X86::LOCK_DEC32m,
+ 0,
+ 0,
+ X86::LOCK_DEC64m,
+ },
+ {
X86::LOCK_OR8mi,
X86::LOCK_OR8mr,
X86::LOCK_OR16mi8,
@@ -1679,7 +1585,7 @@
X86::LOCK_OR32mr,
X86::LOCK_OR64mi8,
X86::LOCK_OR64mi32,
- X86::LOCK_OR64mr
+ X86::LOCK_OR64mr,
},
{
X86::LOCK_AND8mi,
@@ -1692,7 +1598,7 @@
X86::LOCK_AND32mr,
X86::LOCK_AND64mi8,
X86::LOCK_AND64mi32,
- X86::LOCK_AND64mr
+ X86::LOCK_AND64mr,
},
{
X86::LOCK_XOR8mi,
@@ -1705,18 +1611,74 @@
X86::LOCK_XOR32mr,
X86::LOCK_XOR64mi8,
X86::LOCK_XOR64mi32,
- X86::LOCK_XOR64mr
+ X86::LOCK_XOR64mr,
}
};
+// Return the target constant operand for atomic-load-op and do simple
+// translations, such as from atomic-load-add to lock-sub. The return value is
+// one of the following 3 cases:
+// + target-constant, the operand could be supported as a target constant.
+// + empty, the operand is not needed any more with the new op selected.
+// + non-empty, otherwise.
+static SDValue getAtomicLoadArithTargetConstant(SelectionDAG *CurDAG,
+ DebugLoc dl,
+ enum AtomicOpc &Op, EVT NVT,
+ SDValue Val) {
+ if (ConstantSDNode *CN = dyn_cast<ConstantSDNode>(Val)) {
+ int64_t CNVal = CN->getSExtValue();
+ // Quit if not 32-bit imm.
+ if ((int32_t)CNVal != CNVal)
+ return Val;
+ // For atomic-load-add, we could do some optimizations.
+ if (Op == ADD) {
+ // Translate to INC/DEC if ADD by 1 or -1.
+ if ((CNVal == 1) || (CNVal == -1)) {
+ Op = (CNVal == 1) ? INC : DEC;
+ // No more constant operand after being translated into INC/DEC.
+ return SDValue();
+ }
+ // Translate to SUB if ADD by negative value.
+ if (CNVal < 0) {
+ Op = SUB;
+ CNVal = -CNVal;
+ }
+ }
+ return CurDAG->getTargetConstant(CNVal, NVT);
+ }
+
+ // If the value operand is single-used, try to optimize it.
+ if (Op == ADD && Val.hasOneUse()) {
+ // Translate (atomic-load-add ptr (sub 0 x)) back to (lock-sub x).
+ if (Val.getOpcode() == ISD::SUB && X86::isZeroNode(Val.getOperand(0))) {
+ Op = SUB;
+ return Val.getOperand(1);
+ }
+ // A special case for i16, which needs truncating as, in most cases, it's
+ // promoted to i32. We will translate
+ // (atomic-load-add (truncate (sub 0 x))) to (lock-sub (EXTRACT_SUBREG x))
+ if (Val.getOpcode() == ISD::TRUNCATE && NVT == MVT::i16 &&
+ Val.getOperand(0).getOpcode() == ISD::SUB &&
+ X86::isZeroNode(Val.getOperand(0).getOperand(0))) {
+ Op = SUB;
+ Val = Val.getOperand(0);
+ return CurDAG->getTargetExtractSubreg(X86::sub_16bit, dl, NVT,
+ Val.getOperand(1));
+ }
+ }
+
+ return Val;
+}
+
SDNode *X86DAGToDAGISel::SelectAtomicLoadArith(SDNode *Node, EVT NVT) {
if (Node->hasAnyUseOfValue(0))
return 0;
+ DebugLoc dl = Node->getDebugLoc();
+
// Optimize common patterns for __sync_or_and_fetch and similar arith
// operations where the result is not used. This allows us to use the "lock"
// version of the arithmetic instruction.
- // FIXME: Same as for 'add' and 'sub', try to merge those down here.
SDValue Chain = Node->getOperand(0);
SDValue Ptr = Node->getOperand(1);
SDValue Val = Node->getOperand(2);
@@ -1727,6 +1689,8 @@
// Which index into the table.
enum AtomicOpc Op;
switch (Node->getOpcode()) {
+ default:
+ return 0;
case ISD::ATOMIC_LOAD_OR:
Op = OR;
break;
@@ -1736,16 +1700,14 @@
case ISD::ATOMIC_LOAD_XOR:
Op = XOR;
break;
- default:
- return 0;
- }
-
- bool isCN = false;
- ConstantSDNode *CN = dyn_cast<ConstantSDNode>(Val);
- if (CN && (int32_t)CN->getSExtValue() == CN->getSExtValue()) {
- isCN = true;
- Val = CurDAG->getTargetConstant(CN->getSExtValue(), NVT);
+ case ISD::ATOMIC_LOAD_ADD:
+ Op = ADD;
+ break;
}
+
+ Val = getAtomicLoadArithTargetConstant(CurDAG, dl, Op, NVT, Val);
+ bool isUnOp = !Val.getNode();
+ bool isCN = Val.getNode() && (Val.getOpcode() == ISD::TargetConstant);
unsigned Opc = 0;
switch (NVT.getSimpleVT().SimpleTy) {
@@ -1787,13 +1749,20 @@
assert(Opc != 0 && "Invalid arith lock transform!");
- DebugLoc dl = Node->getDebugLoc();
+ SDValue Ret;
SDValue Undef = SDValue(CurDAG->getMachineNode(TargetOpcode::IMPLICIT_DEF,
dl, NVT), 0);
MachineSDNode::mmo_iterator MemOp = MF->allocateMemRefsArray(1);
MemOp[0] = cast<MemSDNode>(Node)->getMemOperand();
- SDValue Ops[] = { Tmp0, Tmp1, Tmp2, Tmp3, Tmp4, Val, Chain };
- SDValue Ret = SDValue(CurDAG->getMachineNode(Opc, dl, MVT::Other, Ops, 7), 0);
+ if (isUnOp) {
+ SDValue Ops[] = { Tmp0, Tmp1, Tmp2, Tmp3, Tmp4, Chain };
+ Ret = SDValue(CurDAG->getMachineNode(Opc, dl, MVT::Other, Ops,
+ array_lengthof(Ops)), 0);
+ } else {
+ SDValue Ops[] = { Tmp0, Tmp1, Tmp2, Tmp3, Tmp4, Val, Chain };
+ Ret = SDValue(CurDAG->getMachineNode(Opc, dl, MVT::Other, Ops,
+ array_lengthof(Ops)), 0);
+ }
cast<MachineSDNode>(Ret)->setMemRefs(MemOp, MemOp + 1);
SDValue RetVals[] = { Undef, Ret };
return CurDAG->getMergeValues(RetVals, 2, dl).getNode();
@@ -2089,15 +2058,10 @@
break;
}
- case ISD::ATOMIC_LOAD_ADD: {
- SDNode *RetVal = SelectAtomicLoadAdd(Node, NVT);
- if (RetVal)
- return RetVal;
- break;
- }
case ISD::ATOMIC_LOAD_XOR:
case ISD::ATOMIC_LOAD_AND:
- case ISD::ATOMIC_LOAD_OR: {
+ case ISD::ATOMIC_LOAD_OR:
+ case ISD::ATOMIC_LOAD_ADD: {
SDNode *RetVal = SelectAtomicLoadArith(Node, NVT);
if (RetVal)
return RetVal;
Modified: llvm/trunk/test/CodeGen/X86/atomic_add.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/atomic_add.ll?rev=164243&r1=164242&r2=164243&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/X86/atomic_add.ll (original)
+++ llvm/trunk/test/CodeGen/X86/atomic_add.ll Wed Sep 19 14:36:58 2012
@@ -178,7 +178,8 @@
define void @sub2(i16* nocapture %p, i32 %v) nounwind ssp {
entry:
; CHECK: sub2:
-; CHECK: negl
+; CHECK-NOT: negl
+; CHECK: subw
%0 = trunc i32 %v to i16 ; <i16> [#uses=1]
%1 = atomicrmw sub i16* %p, i16 %0 monotonic
ret void
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