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// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
// See the LICENSE file in the project root for more information.
#include "jitpch.h"
#ifdef _MSC_VER
#pragma hdrstop
#endif
#include "hashbv.h"
#ifdef DEBUG
void dumpMethod()
{
if (VERBOSE)
GetTlsCompiler()->fgDispBasicBlocks(true);
}
void dumpTreeStack(Compiler *comp, ArrayStack<GenTree *> *stack)
{
printf("=TOS=================\n");
for (int i=0; i<stack->Height(); i++)
{
comp->gtDispNode(stack->Index(i), 0, "");
printf("\n");
}
printf("=====================\n");
}
void dumpArgTable(Compiler *comp, GenTree *call)
{
noway_assert(call->IsCall());
fgArgInfoPtr argInfo = call->gtCall.fgArgInfo;
noway_assert(argInfo != NULL);
unsigned argCount = argInfo->ArgCount();
fgArgTabEntryPtr * argTable = argInfo->ArgTable();
fgArgTabEntryPtr curArgTabEntry = NULL;
JITDUMP("ARG TABLE for call ");
Compiler::printTreeID(call);
JITDUMP(":\n");
for (unsigned i=0; i < argCount; i++)
{
curArgTabEntry = argTable[i];
JITDUMP("entry %d\n", i);
DISPTREE(curArgTabEntry->node);
}
JITDUMP("--------------ARG TABLE END --------------\n");
}
#endif // DEBUG
// state carried over the tree walk, to be used in making
// a splitting decision.
struct SplitData
{
// callbacks to determine if we should split here, in pre and post order traversals
Compiler::fgSplitPredicate *predicatePre;
Compiler::fgSplitPredicate *predicatePost;
GenTree *root; // root stmt of tree being processed
BasicBlock *block;
Rationalizer *thisPhase;
bool continueSubtrees; // whether to continue after splitting off a tree (in pre-order)
};
//------------------------------------------------------------------------------
// RewriteOneQuestion - split a question op into three parts: the test and branch,
// and true and false parts, with accompanying flow
//------------------------------------------------------------------------------
Location Rationalizer::RewriteOneQuestion(BasicBlock *block, GenTree *qmarkTree, GenTree *stmt, GenTree *dst)
{
// First create all the blocks this is going to turn into.
// We end the current block here and insert a diamond
// consisting of the then/else blocks and the remainder, which is
// the point where flow merges back and the rest of the current block will end up
// TODO-Cleanup: avoid creating one of these blocks if that part of the qmark is a NOP
BasicBlock* remainderBlock = comp->fgSplitBlockAfterStatement(block, stmt);
BasicBlock* elseBlock = comp->fgSplitBlockAfterStatement(block, stmt);
BasicBlock* thenBlock = comp->fgSplitBlockAfterStatement(block, stmt);
// wire up the flow between the blocks and adjust their preds
block->bbJumpKind = BBJ_COND;
block->bbJumpDest = elseBlock;
thenBlock->bbJumpKind = BBJ_ALWAYS;
thenBlock->bbJumpDest = remainderBlock;
thenBlock->bbFlags &= ~BBF_JMP_TARGET;
elseBlock->bbJumpKind = BBJ_NONE; // falls through to remainder
elseBlock->bbFlags |= (BBF_JMP_TARGET | BBF_HAS_LABEL);
comp->fgAddRefPred(elseBlock, block);
//JITDUMP("after splitting Q1");
//dumpMethod();
remainderBlock->bbFlags |= (BBF_JMP_TARGET | BBF_HAS_LABEL);
comp->fgAddRefPred(remainderBlock, thenBlock);
comp->fgRemoveRefPred(elseBlock, thenBlock);
//JITDUMP("after splitting Q2");
//dumpMethod();
// remove flag marking this as a question conditional
GenTree *conditionExpr = qmarkTree->gtGetOp1();
assert(conditionExpr->gtFlags & GTF_RELOP_QMARK);
conditionExpr->gtFlags &= ~GTF_RELOP_QMARK;
comp->gtReverseCond(conditionExpr);
// Wire up the jmp part.
// Note that, unlike later Rationalizer passes, the QMarks are done prior to the comma
// processing, and therefore prior to the creation of embedded statements.
// So we can safely re-sequence.
GenTree *jmpStmt = comp->fgNewStmtFromTree(comp->gtNewOperNode(GT_JTRUE, TYP_VOID, qmarkTree->gtGetOp1()), qmarkTree->gtStmt.gtStmtILoffsx);
comp->fgInsertStmtAtEnd(block, jmpStmt);
DBEXEC(TRUE, ValidateStatement(Location(jmpStmt, block)));
//JITDUMP("before splitting Q3");
//dumpMethod();
//DBEXEC(TRUE, comp->fgDebugCheckBBlist());
GenTree *trueExpr = qmarkTree->gtGetOp2()->gtGetOp2();
GenTree *falseExpr = qmarkTree->gtGetOp2()->gtGetOp1();
IL_OFFSETX ilOffset = stmt->gtStmt.gtStmtILoffsx;
comp->fgRemoveStmt(block, stmt, false);
unsigned lclNum = 0;
bool resultUsed = false;
// if the dst of the qmark was a local then we can write directly to it
// otherwise make a temp and then do the indir/field/whatever writeback
if (dst && dst->IsLocal())
{
resultUsed = true;
lclNum = dst->gtLclVarCommon.gtLclNum;
// Increment its lvRefCnt and lvRefCntWtd
comp->lvaTable[lclNum].incRefCnts(block->getBBWeight(comp), comp);
}
else if (qmarkTree->TypeGet() != TYP_VOID)
{
resultUsed = true; // just guessing here
lclNum = comp->lvaGrabTemp(true DEBUGARG("lower question"));
comp->lvaTable[lclNum].lvType = qmarkTree->TypeGet();
// Increment its lvRefCnt and lvRefCntWtd twice, one for the def and one for the use
comp->lvaTable[lclNum].incRefCnts(block->getBBWeight(comp), comp);
comp->lvaTable[lclNum].incRefCnts(block->getBBWeight(comp), comp);
}
// assign the trueExpr into the dst or tmp, insert in thenBlock
if (trueExpr->OperGet() != GT_NOP)
{
if (trueExpr->TypeGet() != TYP_VOID)
{
assert(resultUsed);
trueExpr = CreateTempAssignment(comp, lclNum, trueExpr);
}
GenTree *trueStmt = comp->fgNewStmtFromTree(trueExpr, thenBlock, ilOffset);
comp->fgInsertStmtAtEnd(thenBlock, trueStmt);
}
// assign the falseExpr into the dst or tmp, insert in elseBlock
if (falseExpr->OperGet() != GT_NOP)
{
if (falseExpr->TypeGet() != TYP_VOID)
{
assert(resultUsed);
falseExpr = CreateTempAssignment(comp, lclNum, falseExpr);
}
GenTree *falseStmt = comp->fgNewStmtFromTree(falseExpr, elseBlock, ilOffset);
comp->fgInsertStmtAtEnd(elseBlock, falseStmt);
}
// if the dst is a local we have just written it out
// but if not (like an indir or something) then we copy from the temp we allocated
if (dst && !dst->IsLocal())
{
GenTree *writeback = comp->gtNewAssignNode(dst, comp->gtNewLclvNode(lclNum, qmarkTree->TypeGet()));
GenTree *writeStmt = comp->fgNewStmtFromTree(writeback, remainderBlock, ilOffset);
comp->fgInsertStmtAtBeg(remainderBlock, writeStmt);
}
//JITDUMP("after splitting all");
//dumpMethod();
return Location(jmpStmt, block);
}
//------------------------------------------------------------------------------
// isNodeCallArg - given a context (stack of parent nodes), determine if the TOS is an arg to a call
//------------------------------------------------------------------------------
GenTree *isNodeCallArg(ArrayStack<GenTree *> *parentStack)
{
for (int i = 1; // 0 is current node, so start at 1
i < parentStack->Height();
i++)
{
GenTree *node = parentStack->Index(i);
switch (node->OperGet())
{
case GT_LIST:
case GT_ARGPLACE:
break;
case GT_NOP:
// Currently there's an issue when the rationalizer performs
// the fixup of a call argument: the case is when we remove an
// inserted NOP as a parent of a call introduced by fgMorph;
// when then the rationalizer removes it, the tree stack in the
// walk is not consistent with the node it was just deleted, so the
// solution is just to go 1 level deeper.
// TODO-Cleanup: This has to be fixed in a proper way: make the rationalizer
// correctly modify the evaluation stack when removing treenodes.
if (node->gtOp.gtOp1->gtOper == GT_CALL)
{
return node->gtOp.gtOp1;
}
break;
case GT_CALL:
return node;
default:
return NULL;
}
}
return NULL;
}
//------------------------------------------------------------------------------
// shouldSplitRationalPre - invoked in preorder in a tree walk to determine if
// we should split at this point in the tree, and at this
// point in the walk
//------------------------------------------------------------------------------
bool shouldSplitRationalPre(GenTree *tree, GenTree *parent,
Compiler::fgWalkData *data)
{
if (!parent || parent->gtOper == GT_STMT)
return false;
// the only thing we split in preorder are qmark ops
if ((tree->OperGet() == GT_QMARK)
&& parent->gtOper != GT_ASG)
return true;
return false;
}
//------------------------------------------------------------------------------
// shouldSplitRationalPost - invoked in postorder in a tree walk to determine if
// we should split at this point in the tree, and at this
// point in the walk
//------------------------------------------------------------------------------
bool shouldSplitRationalPost(GenTree *tree, GenTree *parent,
Compiler::fgWalkData *data)
{
if (!parent || parent->gtOper == GT_STMT)
return false;
SplitData *splitData = (SplitData *) data->pCallbackData;
auto phase = splitData->thisPhase;
#ifndef _TARGET_AMD64_
if (tree->OperIsAssignment()
// late args are not truly embedded assigns... or at least they are very limited ones
&& !( isNodeCallArg(data->parentStack) && (tree->gtFlags & GTF_LATE_ARG)))
{
JITDUMP("splitting at assignment\n");
return true;
}
if (tree->IsCall() && !parent->OperIsAssignment())
{
JITDUMP("splitting a nested call\n");
return true;
}
#endif
if ((tree->OperGet() == GT_QMARK)
&& parent->gtOper != GT_ASG)
{
JITDUMP("splitting a question\n");
return true;
}
return false;
}
//------------------------------------------------------------------------------
// fgSpliceTreeBefore - insert the given subtree 'tree' as a top level statement
// placed before top level statement 'insertionPoint'
//------------------------------------------------------------------------------
GenTreeStmt *
Compiler::fgSpliceTreeBefore(BasicBlock* block, GenTreeStmt* insertionPoint, GenTree* tree, IL_OFFSETX ilOffset)
{
assert(tree->gtOper != GT_STMT);
assert(fgBlockContainsStatementBounded(block, insertionPoint));
GenTreeStmt* newStmt = gtNewStmt(tree, ilOffset);
newStmt->CopyCosts(tree);
GenTreePtr newStmtFirstNode = Compiler::fgGetFirstNode(tree);
newStmt->gtStmt.gtStmtList = newStmtFirstNode;
newStmtFirstNode->gtPrev = nullptr;
tree->gtNext = nullptr;
fgInsertStmtBefore(block, insertionPoint, newStmt);
return newStmt;
}
//------------------------------------------------------------------------------
// fgMakeEmbeddedStmt: insert the given subtree as an embedded statement
//
// Arguments:
// block - The block containing the parentStmt, into which the new embedded
// statement will go
// tree - The tree that will be the gtStmtExpr of the new embedded statement
// parentStmt - The top-level statement that 'tree' is embedded in
//
// Return Value:
// A pointer to the new statement.
//
// Assumptions:
// 'tree' is fully contained in the linear order of parentStmt
//
// Notes:
// If 'tree' is at the beginning of the linear order of 'parentStmt', it
// is made into a top-level statement.
GenTreeStmt*
Compiler::fgMakeEmbeddedStmt(BasicBlock* block, GenTree* tree, GenTree* parentStmt)
{
assert(tree->gtOper != GT_STMT);
assert(parentStmt->gtOper == GT_STMT);
assert(fgBlockContainsStatementBounded(block, parentStmt));
GenTreePtr newStmtFirstNode = fgGetFirstNode(tree);
GenTreePtr parentStmtFirstNode = parentStmt->gtStmt.gtStmtList;
GenTreePtr prevStmt = parentStmt;
bool newTopLevelStmt = false;
bool splitParentStmt = false;
if (newStmtFirstNode == parentStmtFirstNode)
{
// If this is the first node of the new statement, split them.
parentStmt->gtStmt.gtStmtList = tree->gtNext;
prevStmt = parentStmt->gtPrev;
splitParentStmt = true;
}
GenTreeStmt* newStmt = gtNewStmt(tree, parentStmt->gtStmt.gtStmtILoffsx); // Use same IL offset as parent statement
newStmt->CopyCosts(tree);
newStmt->gtStmtList = newStmtFirstNode;
if (splitParentStmt && parentStmt->gtStmt.gtStmtIsTopLevel())
{
newTopLevelStmt = true;
tree->gtNext->gtPrev = nullptr;
tree->gtNext = nullptr;
}
else
{
newStmt->gtFlags &= ~(GTF_STMT_TOP_LEVEL);
}
// Does parentStmt already have embedded statements?
// If so, determine where this fits in the linear order.
// Note that if we have the splitParentStmt case, some of parentStmt's embedded statements
// may need to move with the new statement
GenTreePtr nextStmt = parentStmt->gtNext;
GenTreePtr nextLinearNode;
GenTreePtr searchNode;
if (splitParentStmt)
{
nextLinearNode = newStmtFirstNode;
// In this case, we're going to search for the LAST linear node in the new statement
// in order to determine which embedded statements will move with this one.
searchNode = tree;
}
else
{
nextLinearNode = parentStmt->gtStmt.gtStmtList;
// In this case, we're going to search for the FIRST linear node in the new statement
// so that we can insert this after any embedded statements that START before it.
searchNode = newStmtFirstNode;
}
// Remember if we find any embedded statements before encountering 'searchNode'.
bool foundEmbeddedStmts = false;
while (nextStmt != nullptr && nextStmt->gtStmt.gtStmtIsEmbedded())
{
GenTreePtr nextEmbeddedNode = nextStmt->gtStmt.gtStmtList;
while (nextLinearNode != searchNode && nextLinearNode != nextEmbeddedNode)
{
nextLinearNode = nextLinearNode->gtNext;
assert (nextLinearNode != nullptr);
}
if (nextLinearNode == searchNode)
break;
prevStmt = nextStmt;
nextStmt = nextStmt->gtNext;
foundEmbeddedStmts = true;
}
if (newTopLevelStmt)
{
// For this case, we are actually going to insert it BEFORE parentStmt.
// However if we have a new prevStmt (i.e. there are some embedded statements
// to be included in newStmt) then those need to be moved as well.
// Note, however, that all the tree links have alraedy been fixed up.
fgInsertStmtBefore(block, parentStmt, newStmt);
if (foundEmbeddedStmts)
{
GenTreePtr firstEmbeddedStmt = parentStmt->gtNext;
assert(firstEmbeddedStmt->gtStmt.gtStmtIsEmbedded());
assert(prevStmt->gtStmt.gtStmtIsEmbedded());
parentStmt->gtNext = prevStmt->gtNext;
if (parentStmt->gtNext != nullptr)
{
parentStmt->gtNext->gtPrev = parentStmt;
}
else
{
block->bbTreeList->gtPrev = parentStmt;
}
parentStmt->gtPrev = prevStmt;
prevStmt->gtNext = parentStmt;
newStmt->gtNext = firstEmbeddedStmt;
firstEmbeddedStmt->gtPrev = newStmt;
}
}
else
{
fgInsertStmtAfter(block, prevStmt, newStmt);
}
return newStmt;
}
//------------------------------------------------------------------------------
// fgInsertLinearNodeBefore: insert the given single node before 'before'.
//
// Arguments:
// newNode - The node to be inserted
// before - The node to insert it before
//
// Return Value:
// None.
//
// Assumptions:
// Either the callee must ensure that 'before' is part of compCurStmt,
// or before->gtPrev must be non-null
void
Compiler::fgInsertLinearNodeBefore(GenTreePtr newNode, GenTreePtr before)
{
GenTreePtr prevNode = before->gtPrev;
newNode->gtPrev = prevNode;
if (prevNode == nullptr)
{
assert(compCurStmt->gtStmt.gtStmtList == before && compCurStmt->gtStmt.gtStmtIsTopLevel());
}
else
{
prevNode->gtNext = newNode;
}
// Note that 'before' may be the first node in gtStmtList even if its gtPrev is non-null,
// since compCurStmt may be embedded.
if (compCurStmt->gtStmt.gtStmtList == before)
{
compCurStmt->gtStmt.gtStmtList = newNode;
}
newNode->gtNext = before;
before->gtPrev = newNode;
}
//-----------------------------------------------------------------------------------------------
// fgInsertEmbeddedFormTemp: Assign a variable to hold the result of *ppTree, possibly creating a new variable
// and creating a new (possibly embedded) statement for it. The original
// subtree will be replaced with a use of the temp.
//
// Arguments:
// ppTree - a pointer to the child node we will be replacing with a reference to the new temp.
// lclNum - local var to use, or BAD_VAR_NUM to create one
//
// Return Value:
// The new statement.
//
// Assumptions:
// The callee must ensure that '*ppTree' is part of compCurStmt, and that
// compCurStmt is in compCurBB;
GenTreeStmt*
Compiler::fgInsertEmbeddedFormTemp(GenTree** ppTree, unsigned lclNum)
{
GenTree* subTree = *ppTree;
if (lclNum == BAD_VAR_NUM)
{
lclNum = lvaGrabTemp(true DEBUGARG("fgInsertEmbeddedFormTemp is creating a new local variable"));
}
// Increment its lvRefCnt and lvRefCntWtd twice, one for the def and one for the use
lvaTable[lclNum].incRefCnts(compCurBB->getBBWeight(this), this);
lvaTable[lclNum].incRefCnts(compCurBB->getBBWeight(this), this);
GenTreeLclVar* store = gtNewTempAssign(lclNum, subTree)->AsLclVar();
gtSetEvalOrder(store);
subTree->InsertAfterSelf(store);
GenTree* load = new (this, GT_LCL_VAR) GenTreeLclVar(store->TypeGet(), store->AsLclVarCommon()->GetLclNum(), BAD_IL_OFFSET);
gtSetEvalOrder(load);
store->InsertAfterSelf(load);
*ppTree = load;
JITDUMP("fgInsertEmbeddedFormTemp created store :\n");
DISPTREE(store);
GenTreeStmt* stmt = fgMakeEmbeddedStmt(compCurBB, store, compCurStmt);
stmt->gtStmtILoffsx = compCurStmt->gtStmt.gtStmtILoffsx;
#ifdef DEBUG
stmt->gtStmtLastILoffs = compCurStmt->gtStmt.gtStmtLastILoffs;
#endif // DEBUG
return stmt;
}
//------------------------------------------------------------------------------
// RenameUpdatedVars - detect trees that have internal assignments with preceding reads
// of the variables being written.
// Replace the preceding reads with references to copies made in advance
// in order to make breaking out the assignments legal
//------------------------------------------------------------------------------
void Rationalizer::RenameUpdatedVars(Location loc)
{
// A variable which is assigned within the tree will have different
// values at different points in the tree. The rationalizer tries to
// break internal assignments out into their own tree and place those trees before
// the original tree. This could result in changed meaning unless
// we have a way of differentiating between original and modified values
GenTree *statement = loc.tree;
assert(statement->IsStatement());
GenTree *tree = loc.tree->gtStmt.gtStmtExpr;
use->ZeroAll();
usedef->ZeroAll();
rename->ZeroAll();
unexp->ZeroAll();
int *renameMap = (int *) alloca(sizeof(int) * comp->lvaCount);
var_types *renameTypeMap = (var_types *) alloca(sizeof(var_types) * comp->lvaCount);
// find locals that are redefined within the tree
foreach_treenode_execution_order(tree, statement)
{
if (tree->IsLocal())
{
int varIdx = tree->gtLclVarCommon.gtLclNum;
if (tree->gtFlags & GTF_VAR_DEF // definition
|| tree->gtFlags & GTF_VAR_USEDEF // this is a use/def as in x=x+y (only the lhs x is tagged)
|| tree->gtFlags & GTF_VAR_USEASG)// this is a use/def for a x<op>=y
{
if (use->testBit(varIdx))
{
usedef->setBit(varIdx);
}
else
{
unexp->setBit(varIdx);
}
}
else
{
if (usedef->testBit(varIdx))
{
rename->setBit(varIdx);
renameTypeMap[varIdx] = tree->TypeGet();
}
else
{
use->setBit(varIdx); // it's a plain use
}
}
}
}
if (!rename->anySet())
return;
indexType index;
// create the new variables and establish the mapping
// also insert copies before the statement
FOREACH_HBV_BIT_SET(index, rename)
{
JITDUMP("had to rename idx:%d in tree!\n", index);
DISPTREE(statement);
unsigned tmpIndex =
renameMap[index] =
comp->lvaGrabTemp(true DEBUGARG("rationalize renaming"));
LclVarDsc *newVar = &comp->lvaTable[tmpIndex];
newVar->lvType = renameTypeMap[index];
// Increment its lvRefCnt and lvRefCntWtd
comp->lvaTable[tmpIndex].incRefCnts(loc.block->getBBWeight(comp), comp);
// only need a copy for exposed uses, otherwise a def is the first occurence
if (!unexp->testBit(index))
{
GenTree *write = comp->gtNewAssignNode(comp->gtNewLclvNode(renameMap[index], newVar->TypeGet()),
comp->gtNewLclvNode((int)index, newVar->TypeGet()));
write = comp->fgNewStmtFromTree(write, statement->gtStmt.gtStmtILoffsx);
comp->fgInsertStmtBefore(loc.block, statement, write);
JITDUMP("New write tree:\n");
DISPTREE(write);
}
}
NEXT_HBV_BIT_SET;
hashBv *seenUse = hashBv::Create(this->comp);
hashBv *seenRedef = hashBv::Create(this->comp);
// we are looking for a def after use
// don't just start renaming if it kicks off with a def
foreach_treenode_execution_order(tree, statement)
{
if (tree->IsLocal())
{
int varIdx = tree->gtLclVarCommon.gtLclNum;
if (rename->testBit(varIdx))
{
if (tree->gtFlags & GTF_VAR_DEF
//|| tree->gtFlags & GTF_VAR_USEDEF
|| tree->gtFlags & GTF_VAR_USEASG)
{
if (seenUse->testBit(varIdx))
seenRedef->setBit(varIdx);
}
else
{
seenUse->setBit(varIdx);
}
if (!seenRedef->testBit(varIdx))
{
tree->gtLclVarCommon.SetLclNum(renameMap[varIdx]);
}
}
}
}
}
// return op that is the store equivalent of the given load opcode
genTreeOps storeForm(genTreeOps loadForm)
{
switch (loadForm)
{
case GT_LCL_VAR:
return GT_STORE_LCL_VAR;
case GT_LCL_FLD:
return GT_STORE_LCL_FLD;
case GT_REG_VAR:
noway_assert(!"reg vars only supported in classic backend\n");
unreached();
default:
noway_assert(!"not a data load opcode\n");
unreached();
}
}
// return op that is the addr equivalent of the given load opcode
genTreeOps addrForm(genTreeOps loadForm)
{
switch (loadForm)
{
case GT_LCL_VAR:
return GT_LCL_VAR_ADDR;
case GT_LCL_FLD:
return GT_LCL_FLD_ADDR;
default:
noway_assert(!"not a data load opcode\n");
unreached();
}
}
// copy the flags determined by mask from src to dst
void copyFlags(GenTree *dst, GenTree *src, unsigned mask)
{
dst->gtFlags &= ~mask;
dst->gtFlags |= (src->gtFlags & mask);
}
//------------------------------------------------------------------------------
// RewriteQuestions - transform qmark ops, expanding them into multiple blocks
// They should all be at the top level or immediately under an
// assignment at this point
//------------------------------------------------------------------------------
Location Rationalizer::RewriteQuestions(Location loc)
{
GenTree *topNode = loc.tree->gtStmt.gtStmtExpr;
// we should have things broken up so all questions are at top level
if (topNode->gtOper == GT_QMARK)
{
loc = RewriteOneQuestion(loc.block, topNode, loc.tree, NULL);
return loc;
}
else if (topNode->gtOper == GT_ASG)
{
// hope there's never a QMARK on the LHS
assert(topNode->gtGetOp1()->gtOper != GT_QMARK);
GenTree *questionOp = topNode->gtGetOp2();
if (questionOp->gtOper != GT_QMARK)
return loc;
loc = RewriteOneQuestion(loc.block, questionOp, loc.tree, topNode->gtGetOp1());
return loc;
}
else
{
return loc;
}
}
//--------------------------------------------------------------------------------------
// RewriteTopLevelComma - split a top-level comma into two top level statements.
// returns (as out params) the two new locations
//--------------------------------------------------------------------------------------
void Rationalizer::RewriteTopLevelComma(Location loc, Location* out1, Location* out2)
{
GenTreeStmt* commaStmt = loc.tree->AsStmt();
GenTree* commaOp = commaStmt->gtStmtExpr;
assert(commaOp->OperGet() == GT_COMMA);
JITDUMP("splitting top level comma!\n");
GenTreeStmt* newStatement1 = comp->fgSpliceTreeBefore(loc.block, commaStmt, commaOp->gtGetOp1(), commaStmt->gtStmtILoffsx);
GenTreeStmt* newStatement2 = comp->fgSpliceTreeBefore(loc.block, commaStmt, commaOp->gtGetOp2(), commaStmt->gtStmtILoffsx);
comp->fgRemoveStmt(loc.block, commaStmt, false);
// these two subtrees still need to be processed
loc = Location(newStatement1, loc.block);
*out1 = Location(newStatement1, loc.block);
*out2 = Location(newStatement2, loc.block);
}
//--------------------------------------------------------------------------------------
// TreeTransformRationalization - Run the set of rationalizations on one statement that
// transforms its underlying trees but doesn't perform
// tree walks to introduce new statements.
//--------------------------------------------------------------------------------------
Location Rationalizer::TreeTransformRationalization(Location loc)
{
top:
assert(loc.tree);
DBEXEC(TRUE, didSplit = false);
JITDUMP("Tree Transform Rationalization: BB%02u\n", loc.block->bbNum);
DISPTREE(loc.tree);
JITDUMP("\n");
comp->compCurStmt = loc.tree;
comp->compCurBB = loc.block;
// top level comma is a special case
if (loc.tree->gtStmt.gtStmtExpr->OperGet() == GT_COMMA)
{
Location loc1, loc2;
RewriteTopLevelComma(loc, &loc1, &loc2);
loc = loc1;
goto top;
}
DBEXEC(TRUE, loc.Validate());
#ifdef LEGACY_BACKEND
if (comp->compQmarkUsed)
{
loc = RewriteQuestions(loc);
}
#endif // LEGACY_BACKEND
DBEXEC(TRUE, ValidateStatement(loc));
loc = RewriteSimpleTransforms(loc);
DBEXEC(TRUE, ValidateStatement(loc));
JITDUMP("comma processing top level statment:\n");
DISPTREE(loc.tree);
JITDUMP("\n");
DuplicateCommaProcessOneTree(comp, this, loc.block, loc.tree);
DBEXEC(didSplit, comp->fgDebugCheckBBlist());
return loc;
}
//------------------------------------------------------------------------------
// MorphAsgIntoStoreLcl -
// Receives an assignment of type GT_ASG(Lhs, Rhs) where:
// -- Lhs can be GT_LCL_VAR or GT_LCL_FLD
// -- Rhs is an arbitrary tree and converts that into its corresponding
// store local form.
//
// Returns the tree converted into GT_STORE_LCL_VAR or GT_STORE_LCL_FLD form.
//
// If stmt is null, this is a newly created tree that is not yet contained in
// a stmt.
//------------------------------------------------------------------------------
void Rationalizer::MorphAsgIntoStoreLcl(GenTreeStmt* stmt, GenTreePtr pTree)
{
assert(pTree->OperGet() == GT_ASG);
GenTreePtr lhs = pTree->gtGetOp1();
GenTreePtr rhs = pTree->gtGetOp2();
assert(lhs->OperGet() == GT_LCL_VAR ||
lhs->OperGet() == GT_LCL_FLD);
#ifdef DEBUG
if (lhs->OperGet() == GT_LCL_VAR)
{
JITDUMP("rewriting GT_ASG(GT_LCL_VAR, X) to GT_STORE_LCL_VAR(X)\n");
}
else
{
assert(lhs->OperGet() == GT_LCL_FLD);
JITDUMP("rewriting GT_ASG(GT_LCL_FLD, X) to GT_STORE_LCL_FLD(X)\n");
}
#endif // DEBUG
GenTreeLclVarCommon* var = lhs->AsLclVarCommon();
pTree->SetOper(storeForm(var->OperGet()));
GenTreeLclVarCommon* dst = pTree->AsLclVarCommon();
dst->SetLclNum(var->gtLclNum);
dst->SetSsaNum(var->gtSsaNum);
dst->gtType = lhs->gtType;
if (lhs->OperGet() == GT_LCL_FLD)
{
dst->gtLclFld.gtLclOffs = lhs->gtLclFld.gtLclOffs;
dst->gtLclFld.gtFieldSeq = lhs->gtLclFld.gtFieldSeq;
}
copyFlags(dst, var, GTF_LIVENESS_MASK);
dst->gtOp.gtOp1 = rhs;
if (stmt != nullptr)
{
assert(stmt->OperGet() == GT_STMT);
Compiler::fgDeleteTreeFromList(stmt, lhs);
}
DISPNODE(pTree);
JITDUMP("\n");
}
//------------------------------------------------------------------------------
// CreateTempAssignment -
// Constructs an assignment where its left hand side is a GenTree node
// representing the given local variable number and the right hand side is
// the given tree.
//
// This calls gtNewTempAssig(), which produces a GT_STORE_LCL_VAR instead of a
// GT_ASG when we are in linear order, which we are in the Rationalizer.
//
//------------------------------------------------------------------------------
GenTreePtr Rationalizer::CreateTempAssignment(Compiler* comp, unsigned lclNum, GenTreePtr rhs)
{
GenTreePtr gtAsg = comp->gtNewTempAssign(lclNum, rhs);
return gtAsg;
}
// turn "comma(lcl x, lcl x)" into "lcl x"
// this is produced by earlier transformations
void Rationalizer::DuplicateCommaProcessOneTree(Compiler *comp, Rationalizer *irt, BasicBlock *block, GenTree *statement)
{
SplitData tmpState = {0};
tmpState.root = statement;
tmpState.continueSubtrees = true;
tmpState.thisPhase = irt;
tmpState.block = block;
assert(statement->IsStatement());
comp->fgWalkTree(&(statement->gtStmt.gtStmtExpr),
NULL,
CommaHelper,
&tmpState);
#if 0
JITDUMP("resulting block\n");
DBEXEC(VERBOSE, comp->fgDispBasicBlocks(block, block, true));
#endif
}
// call args have other pointers to them which must be fixed up if
// they are replaced
void Compiler::fgFixupIfCallArg(ArrayStack<GenTree *> *parentStack,
GenTree *oldChild,
GenTree *newChild)
{
GenTree *parentCall = isNodeCallArg(parentStack);
if (!parentCall)
{
DBEXEC(VERBOSE, dumpTreeStack(GetTlsCompiler(), parentStack));
return;
}
// we have replaced an arg, so update pointers in argtable
fgFixupArgTabEntryPtr(parentCall, oldChild, newChild);
}
//------------------------------------------------------------------------
// fgFixupArgTabEntryPtr: Fixup the fgArgTabEntryPtr of parentCall after
// replacing oldArg with newArg
//
// Arguments:
// parentCall - a pointer to the parent call node
// oldArg - the original argument node
// newArg - the replacement argument node
//
void Compiler::fgFixupArgTabEntryPtr(GenTreePtr parentCall,
GenTreePtr oldArg,
GenTreePtr newArg)
{
assert(parentCall != nullptr);
assert(oldArg != nullptr);
assert(newArg != nullptr);
JITDUMP("parent call was :\n");
DISPTREE(parentCall);
JITDUMP("old child was :\n");
DISPTREE(oldArg);
if (oldArg->gtFlags & GTF_LATE_ARG)
{
newArg->gtFlags |= GTF_LATE_ARG;
}
else
{
fgArgTabEntryPtr fp = Compiler::gtArgEntryByNode(parentCall, oldArg);
assert(fp->node == oldArg);
fp->node = newArg;
}
JITDUMP("parent call:\n");
DISPTREE(parentCall);
}
//------------------------------------------------------------------------
// CommaUselessChild: removes commas with useless first child:
// - Turns "comma(lcl x, Y)" into "Y"
// - Turns "comma(NOP, Y)" into "Y"
//
// Arguments:
// ppTree - a pointer to the parent pointer for a comma node
// data - the traversal data
//
// Return Value:
// Returns "true" if it found a comma with a useless child, and transformed it.
//
// Notes:
// These comma forms are produced by earlier transformations.
bool
Rationalizer::CommaUselessChild(GenTree **ppTree, Compiler::fgWalkData *data)
{
GenTree *tree = *ppTree;
GenTree *subChild1, *subChild2;
SplitData *tmpState = (SplitData *) data->pCallbackData;
assert(tree->OperGet() == GT_COMMA);
subChild1 = tree->gtGetOp1();
subChild2 = tree->gtGetOp2();
if (subChild1->OperGet() == GT_COMMA)
{
data->parentStack->Push(tree->gtOp.gtOp1);
CommaUselessChild(&(tree->gtOp.gtOp1), data);
subChild1 = tree->gtGetOp1();
data->parentStack->Pop();
}
if (subChild2->OperGet() == GT_COMMA)
{
data->parentStack->Push(tree->gtOp.gtOp2);
CommaUselessChild(&(tree->gtOp.gtOp2), data);
subChild2 = tree->gtGetOp2();
data->parentStack->Pop();
}
if (subChild1 != nullptr &&
subChild2 != nullptr &&
(subChild1->OperIsLocalRead() ||
(subChild1->OperGet() == GT_NOP && subChild1->gtGetOp1() == nullptr)))
{
JITDUMP("found comma subtree with useless child:\n");
DISPTREE(tree);
JITDUMP("\n");
#ifdef DEBUG
if (isNodeCallArg(data->parentStack))
{
JITDUMP("PARENT TREE:\n");
DISPTREE(isNodeCallArg(data->parentStack));
JITDUMP("\n");
}
#endif // DEBUG
Compiler::fgSnipNode(tmpState->root->AsStmt(), tree);
Compiler::fgSnipNode(tmpState->root->AsStmt(), subChild1);
*ppTree = subChild2;
if (tree->gtFlags & GTF_LATE_ARG)
{
subChild2->gtFlags |= GTF_LATE_ARG;
// If we just have a bare local as a late ("SETUP") arg then that is effectively a NOP
// however if that local node is a last use, codegen will not count it as such, and blow up
// so get rid of those here
if (subChild2->IsLocal())
subChild2->gtBashToNOP();
}
tmpState->thisPhase->comp->fgFixupIfCallArg(data->parentStack, tree, subChild2);
return true;
}
return false;
}
// Call CommaUselessChild() to turn "comma(lcl x, lcl x)" into "lcl x"
Compiler::fgWalkResult Rationalizer::CommaHelper(GenTree **ppTree, Compiler::fgWalkData *data)
{
GenTree *tree = *ppTree;
Compiler* comp = data->compiler;
SplitData *tmpState = (SplitData *) data->pCallbackData;
if (tree->OperGet() == GT_COMMA &&
CommaUselessChild(ppTree, data))
{
return Compiler::WALK_SKIP_SUBTREES;
}
return Compiler::WALK_CONTINUE;
}
// rewrite ASG nodes as either local store or indir store forms
// also remove ADDR nodes
Location Rationalizer::RewriteSimpleTransforms(Location loc)
{
GenTreeStmt * statement = (loc.tree)->AsStmt();
GenTree * tree = statement->gtStmt.gtStmtExpr;
JITDUMP("RewriteSimpleTransforms, with statement:\n");
DISPTREE(statement);
JITDUMP("\n");
if (statement->gtStmtIsTopLevel())
{
if (tree->OperGet() == GT_COMMA)
{
Location loc1, loc2;
RewriteTopLevelComma(loc, &loc1, &loc2);
RewriteSimpleTransforms(loc1);
RewriteSimpleTransforms(loc2);
return loc1;
}
else if (tree->OperKind() & GTK_CONST)
{
// Don't bother generating a top level statement that is just a constant.
// We can get these if we decide to hoist a large constant value out of a loop.
tree->gtBashToNOP();
}
}
SplitData tmpState = {0};
tmpState.root = statement;
tmpState.continueSubtrees = true;
tmpState.thisPhase = this;
tmpState.block = loc.block;
comp->fgWalkTree(&(statement->gtStmt.gtStmtExpr),
SimpleTransformHelper,
NULL,
&tmpState);
tree = statement->gtStmt.gtStmtExpr;
if (tree->OperIsLocalRead())
{
comp->lvaTable[tree->AsLclVarCommon()->gtLclNum].decRefCnts(comp->compCurBB->getBBWeight(comp), comp);
tree->gtBashToNOP();
}
JITDUMP("After simple transforms:\n");
DISPTREE(statement);
JITDUMP("\n");
return loc;
}
// RecursiveRewriteComma
//
// This routine deals with subtrees composed entirely of commas, and the expressions that hang off of them.
// The degenerate case is a single comma but (?????)
//
// ppTree : pointer to a link to a comma node
// discard: true if any value produced by the node will ultimately be discarded.
// In a tree of commas with some non-comma expressions hanging off the terminal commas,
// ultimately all results of those expressions will be discarded except for
// the expression reached by following the second link of of all commas on a path from the base
// ex: in "comma(comma(exp1, exp2), comma(exp3, comma(exp4, exp5)))"
// the only expression whose value makes it to the root of the comma tree is exp5
// nested: true if there is another comma as the parent
//
void Rationalizer::RecursiveRewriteComma(GenTree **ppTree, Compiler::fgWalkData *data, bool discard, bool nested)
{
GenTree* comma = *ppTree;
assert(comma->gtOper == GT_COMMA);
GenTreePtr op2 = comma->gtOp.gtOp2;
GenTreePtr op1 = comma->gtOp.gtOp1;
SplitData *tmpState = (SplitData *) data->pCallbackData;
GenTreePtr stmt = tmpState->root;
Compiler* comp = data->compiler;
JITDUMP("recursive rewrite comma :\n");
DISPTREE(comma);
JITDUMP("\n");
if (op1->gtOper == GT_COMMA)
{
// embed all of the expressions reachable from op1.
// Since they feed into op1, their results are discarded (not used up the tree)
RecursiveRewriteComma(&(comma->gtOp.gtOp1), data, true, true);
}
// Although most top-level commas have already been handled, we may create new ones
// (for example by splitting a comma above another comma).
Compiler::fgSnipNode(stmt->AsStmt(), comma);
*ppTree = op2;
JITDUMP("pptree now : ");
DISPNODE(op2);
if (data->parentStack->Top() == comma)
{
data->parentStack->Pop();
data->parentStack->Push(op2);
}
GenTree* commaNext = comma->gtNext;
op1 = comma->gtOp.gtOp1;
// op1 of the comma will now be a new statement, either top-level or embedded
// depending on the execution order.
// The comma is simply eliminated.
GenTreePtr newStmt = comp->fgMakeEmbeddedStmt(tmpState->block, op1, tmpState->root);
if (!nested)
comp->fgFixupIfCallArg(data->parentStack, comma, *ppTree);
JITDUMP("Split comma into %s statements. New statement:\n", (newStmt->gtFlags & GTF_STMT_TOP_LEVEL) ? "top-level" : "embedded");
DISPTREE(newStmt);
JITDUMP("\nOld statement:\n");
DISPTREE(stmt);
JITDUMP("\n");
(void) ((Rationalizer *)tmpState->thisPhase)->RewriteSimpleTransforms(Location(newStmt, tmpState->block));
// In a sense, assignment nodes have two destinations: 1) whatever they are writing to
// and 2) they also produce the value that was written so their parent can consume it.
// In the case where the parent is going to consume the value,
// insert the assign as an embedded statement and clone the destination to replace itself in the tree.
if (op2->OperGet() == GT_ASG && !discard)
{
JITDUMP("op2 of comma was an assignment, doing additional work\n");
assert(op2->gtNext);
GenTree* dst = op2->gtOp.gtOp1;
GenTree* newSrc = nullptr;
GenTreeStmt* newStmt;
newStmt = comp->fgMakeEmbeddedStmt(tmpState->block, op2, tmpState->root);
// can this happen ?
assert(dst->OperIsLocal());
newSrc = comp->gtClone(dst);
newSrc->gtFlags &= ~GTF_VAR_DEF;
*ppTree = newSrc;
comp->fgInsertTreeInListBefore(newSrc, commaNext, stmt->AsStmt());
JITDUMP("Split comma into %s statements. New statement:\n", (newStmt->gtFlags & GTF_STMT_TOP_LEVEL) ? "top-level":"embedded");
DISPTREE(newStmt);
JITDUMP("\nOld statement:\n");
DISPTREE(stmt);
JITDUMP("\n");
(void) ((Rationalizer *)tmpState->thisPhase)->RewriteSimpleTransforms(Location(newStmt, tmpState->block));
if (!nested)
comp->fgFixupIfCallArg(data->parentStack, comma, newSrc);
(void) ((Rationalizer *)tmpState->thisPhase)->RewriteSimpleTransforms(Location(newStmt, tmpState->block));
return;
}
JITDUMP("\nreturning from RecursiveRewriteComma\n");
}
//------------------------------------------------------------------------
// RewriteOneComma: Rewrites the trees to remove a comma
//
// Arguments:
// ppTree - a pointer to the parent pointer for a comma node
// data - the traversal data
//
// Return Value:
// None.
//
// Assumptions:
// This method is always called during a traversal (hence the fgWalkData).
// 'ppTree' must point to a GT_COMMA GenTreePtr
//
// Notes:
// If op1 of the comma is a (unused) lclVar, it is deleted by CommmaUselessChild()
void Rationalizer::RewriteOneComma(GenTree **ppTree, Compiler::fgWalkData *data)
{
GenTreePtr comma = *ppTree;
Compiler* comp = data->compiler;
SplitData* tmpState = (SplitData *) data->pCallbackData;
GenTreePtr stmt = tmpState->root;
assert(comma->gtOper == GT_COMMA);
GenTreePtr op2 = comma->gtOp.gtOp2;
GenTreePtr op1 = comma->gtOp.gtOp1;
// Remove the comma from the tree; we know it has non-null gtPrev, otherwise
// we would have handled it as a top-level comma.
assert (comma->gtPrev != nullptr);
JITDUMP("Rationalizing comma:");
DISPNODE(comma);
if (!CommaUselessChild(ppTree, data))
{
// Set 'discard' to true when the comma tree does not return a value
// If the comma's type is TYP_VOID then 'discard' is set to true
// otherwise 'discard' is set to false
bool discard = (comma->TypeGet() == TYP_VOID);
RecursiveRewriteComma(ppTree, data, discard, false);
}
}
// Rewrite InitBlk involving SIMD vector into stlcl.var of a SIMD type.
//
// Arguments:
// ppTree - A pointer-to-a-pointer for the GT_INITBLK
// fgWalkData - A pointer to tree walk data providing the context
//
// Return Value:
// None.
//
// TODO-Cleanup: Once SIMD types are plumbed through the frontend, this will no longer
// be required.
//
void Rationalizer::RewriteInitBlk(GenTreePtr* ppTree, Compiler::fgWalkData* data)
{
#ifdef FEATURE_SIMD
Compiler* comp = data->compiler;
// No lowering is needed for non-SIMD nodes, so early out if featureSIMD is not enabled.
if (!comp->featureSIMD)
{
return;
}
// See if this is a SIMD initBlk that needs to be changed to a simple st.lclVar.
GenTreeInitBlk* tree = (*ppTree)->AsInitBlk();
// Is the dstAddr is addr of a SIMD type lclVar?
GenTreePtr dstAddr = tree->Dest();
if (dstAddr->OperGet() != GT_ADDR)
{
return;
}
GenTree* dst = dstAddr->gtGetOp1();
var_types baseType = comp->getBaseTypeOfSIMDLocal(dst);
if (baseType == TYP_UNKNOWN)
{
return;
}
CORINFO_CLASS_HANDLE typeHnd = comp->lvaTable[dst->AsLclVarCommon()->gtLclNum].lvVerTypeInfo.GetClassHandle();
unsigned simdLocalSize = comp->getSIMDTypeSizeInBytes(typeHnd);
JITDUMP("Rewriting SIMD InitBlk\n");
DISPTREE(tree);
// Get rid of the parent node in GT_ADDR(GT_LCL_VAR)
comp->fgSnipInnerNode(dstAddr);
assert((dst->gtFlags >F_VAR_USEASG) == 0);
// Remove 'size' from execution order
// There are currently only three sizes supported: 8 bytes, 16 bytes or the vector register length.
GenTreeIntConCommon* sizeNode = tree->Size()->AsIntConCommon();
unsigned int size = (unsigned int) roundUp(sizeNode->IconValue(), TARGET_POINTER_SIZE);
var_types simdType = comp->getSIMDTypeForSize(size);
assert(roundUp(simdLocalSize, TARGET_POINTER_SIZE) == size);
comp->fgSnipInnerNode(sizeNode);
GenTree* initVal = tree->InitVal();
GenTreeSIMD* simdTree = new (comp, GT_SIMD) GenTreeSIMD(simdType, initVal, SIMDIntrinsicInit, baseType, (unsigned)sizeNode->IconValue());
dst->SetOper(GT_STORE_LCL_VAR);
dst->gtType = simdType;
dst->gtOp.gtOp1 = simdTree;
dst->gtFlags |= (simdTree->gtFlags & GTF_ALL_EFFECT);
initVal->gtNext = simdTree;
simdTree->gtPrev = initVal;
simdTree->gtNext = dst;
dst->gtPrev = simdTree;
GenTree* nextNode = tree->gtNext;
dst->gtNext = nextNode;
if (nextNode != nullptr)
{
nextNode->gtPrev = dst;
}
*ppTree = dst;
JITDUMP("After rewriting SIMD InitBlk:\n");
DISPTREE(*ppTree);
JITDUMP("\n");
#endif // FEATURE_SIMD
}
// Transform CopyBlk involving SIMD vectors into stlclvar or stind of a SIMD type.
// Transformation is done if either src or dst are known to be SIMD vectors.
//
// Arguments:
// ppTree - A pointer-to-a-pointer for the GT_COPYBLK
// fgWalkData - A pointer to tree walk data providing the context
//
// Return Value:
// None.
//
// If either the source or the dst are known to be SIMD (a lclVar or SIMD intrinsic),
// get the simdType (TYP_DOUBLE or a SIMD type for SSE2) from the size of the SIMD node.
//
// For the source:
// - If it is a SIMD intrinsic or a lvSIMDType lclVar, change the node type to simdType.
// - Otherwise, add a GT_IND of simdType.
// For the dst:
// - If it is a lclVar of a SIMD type, chanage the node type to simdType.
// - Otherwise, change it to a GT_STORE_IND of simdType
//
// TODO-Cleanup: Once SIMD types are plumbed through the frontend, this will no longer
// be required.
//
void Rationalizer::RewriteCopyBlk(GenTreePtr* ppTree, Compiler::fgWalkData* data)
{
#ifdef FEATURE_SIMD
Compiler* comp = data->compiler;
// No need to transofrm non-SIMD nodes, if featureSIMD is not enabled.
if (!comp->featureSIMD)
{
return;
}
// See if this is a SIMD copyBlk
GenTreeCpBlk* tree = (*ppTree)->AsCpBlk();
genTreeOps oper = GT_NONE;
GenTreePtr dstAddr = tree->Dest();
GenTree* srcAddr = tree->Source();
// Do not transform if neither src or dst is known to be a SIMD type.
// If src tree type is something we cannot reason but if dst is known to be of a SIMD type
// we will treat src tree as a SIMD type and vice versa.
if (!(comp->isAddrOfSIMDType(srcAddr) || comp->isAddrOfSIMDType(dstAddr)))
{
return;
}
// At this point it is known to be a copyblk of SIMD vectors and we can
// start transforming the original tree. Prior to this point do not perform
// any modifications to the original tree.
JITDUMP("\nRewriting SIMD CopyBlk\n");
DISPTREE(tree);
// Remove 'size' from execution order
// There are currently only three sizes supported: 8 bytes, 12 bytes, 16 bytes or the vector register length.
GenTreeIntConCommon* sizeNode = tree->Size()->AsIntConCommon();
var_types simdType = comp->getSIMDTypeForSize((unsigned int) sizeNode->IconValue());
comp->fgSnipInnerNode(sizeNode);
// Is destination a lclVar which is not an arg?
// If yes then we can turn it to a stlcl.var, otherwise turn into stind.
GenTree* simdDst = nullptr;
if (dstAddr->OperGet() == GT_ADDR && comp->isSIMDTypeLocal(dstAddr->gtGetOp1()))
{
// Get rid of parent node in GT_ADDR(GT_LCL_VAR)
comp->fgSnipInnerNode(dstAddr);
simdDst = dstAddr->gtGetOp1();
simdDst->gtType = simdType;
oper = GT_STORE_LCL_VAR;
// For structs that are padded (e.g. Vector3f, Vector3i), the morpher will have marked them
// as GTF_VAR_USEASG. Unmark them.
simdDst->gtFlags &= ~(GTF_VAR_USEASG);
}
else
{
// Address of a non-local var
simdDst = dstAddr;
oper = GT_STOREIND;
}
// Src: Get rid of parent node of GT_ADDR(..) if its child happens to be of a SIMD type.
GenTree* simdSrc = nullptr;
if (srcAddr->OperGet() == GT_ADDR && varTypeIsSIMD(srcAddr->gtGetOp1()))
{
comp->fgSnipInnerNode(srcAddr);
simdSrc = srcAddr->gtGetOp1();
}
else
{
// Since destination is known to be a SIMD type, src must be a SIMD type too
// though we cannot figure it out easily enough. Transform src into
// GT_IND(src) of simdType.
//
// We need to initialize costs on indir so that CopyCosts() while creating
// an addrmode will not hit asserts. These costs are not used further down
// but setting them to a reasonable value based on the logic in gtSetEvalOrder().
GenTree* indir = comp->gtNewOperNode(GT_IND, simdType, srcAddr);
indir->SetCosts(IND_COST_EX, 2);
srcAddr->InsertAfterSelf(indir);
tree->gtGetOp1()->gtOp.gtOp2 = indir;
simdSrc = indir;
}
simdSrc->gtType = simdType;
// Change cpblk to either a st.lclvar or st.ind.
// At this point we are manipulating cpblk node with the knowledge of
// its internals (i.e. op1 is the size node, and the src & dst are in a GT_LIST on op2).
// This logic might need to be changed if we ever restructure cpblk node.
assert(simdDst != nullptr);
assert(simdSrc != nullptr);
GenTree *newTree = nullptr;
GenTree* list = tree->gtGetOp1();
if (oper == GT_STORE_LCL_VAR)
{
// get rid of the list node
comp->fgSnipInnerNode(list);
newTree = simdDst;
newTree->SetOper(oper);
newTree->gtOp.gtOp1 = simdSrc;
newTree->gtType = simdType;
newTree->gtFlags |= (simdSrc->gtFlags & GTF_ALL_EFFECT);
simdSrc->gtNext = newTree;
newTree->gtPrev = simdSrc;
}
else
{
assert(oper == GT_STOREIND);
newTree = list;
newTree->SetOper(oper);
newTree->gtType = simdType;
newTree->gtFlags |= (simdSrc->gtFlags & GTF_ALL_EFFECT);
newTree->gtOp.gtOp1 = simdDst;
newTree->gtOp.gtOp2 = simdSrc;
}
assert(newTree != nullptr);
GenTree* nextNode = tree->gtNext;
newTree->gtNext = nextNode;
if (nextNode != nullptr)
{
nextNode->gtPrev = newTree;
}
*ppTree = newTree;
JITDUMP("After rewriting SIMD CopyBlk:\n");
DISPTREE(*ppTree);
JITDUMP("\n");
#endif // FEATURE_SIMD
}
// Rewrite GT_LDOBJ of SIMD Vector as GT_IND(GT_LEA(ldobj.op1)) of a SIMD type.
//
// Arguments:
// ppTree - A pointer-to-a-pointer for the GT_LDOBJ
// fgWalkData - A pointer to tree walk data providing the context
//
// Return Value:
// None.
//
// TODO-Cleanup: Once SIMD types are plumbed through the frontend, this will no longer
// be required.
//
void Rationalizer::RewriteLdObj(GenTreePtr* ppTree, Compiler::fgWalkData* data)
{
#ifdef FEATURE_SIMD
Compiler* comp = data->compiler;
GenTreeLdObj* ldObj = (*ppTree)->AsLdObj();
// For UNIX struct passing, we can have LdObj nodes for arguments.
// For other cases, we should never see a non-SIMD type here.
#ifdef FEATURE_UNIX_AMD64_STRUCT_PASSING
if (!varTypeIsSIMD(ldObj))
{
return;
}
#endif // FEATURE_UNIX_AMD64_STRUCT_PASSING
// Should come here only if featureSIMD is enabled
noway_assert(comp->featureSIMD);
// On we should only call this with a SIMD type.
noway_assert(varTypeIsSIMD(ldObj));
var_types simdType = ldObj->TypeGet();
// If the operand of ldobj is a GT_ADDR(GT_LCL_VAR) and LclVar is known to be a SIMD type,
// replace ldobj by GT_LCL_VAR.
GenTree* srcAddr = ldObj->gtGetOp1();
if (srcAddr->OperGet() == GT_ADDR && comp->isSIMDTypeLocal(srcAddr->gtGetOp1()))
{
GenTree* src = srcAddr->gtGetOp1();
comp->fgSnipInnerNode(srcAddr);
// It is possible for the ldobj to be the last node in the tree, if its result is
// not actually stored anywhere and is not eliminated.
// This can happen with an unused SIMD expression involving a localVar or temporary value,
// where the SIMD expression is returning a non-SIMD value, and the expression is sufficiently
// complex (e.g. a call to vector * scalar which is inlined but not an intrinsic).
// The ldobj of the localVar is not eliminated, because it involves an indirection,
// and therefore appears potentially unsafe to eliminate. However, when we transform the ldobj into
// a plain localVar during the Rationalizer, we need to correctly handle the case where it has
// no parent.
// This happens, for example, with this source code:
// Vector4.Dot(default(Vector4) * 2f, Vector4.One);
if (ldObj->gtNext == nullptr)
{
SplitData *tmpState = (SplitData *) data->pCallbackData;
comp->fgSnipNode(tmpState->root->AsStmt(), ldObj);
}
else
{
comp->fgSnipInnerNode(ldObj);
}
comp->fgFixupIfCallArg(data->parentStack, ldObj, src);
src->gtType = simdType;
*ppTree = src;
}
else
{
ldObj->SetOper(GT_IND);
ldObj->gtType = simdType;
}
#else
// we should never reach without feature SIMD
assert(!"Unexpected Ldobj during rationalization\n");
unreached();
#endif
}
// RewriteNodeAsCall : Replace the given tree node by a GT_CALL.
//
// Arguments:
// ppTree - A pointer-to-a-pointer for the tree node
// fgWalkData - A pointer to tree walk data providing the context
// callHnd - The method handle of the call to be generated
// entryPoint - The method entrypoint of the call to be generated
// args - The argument list of the call to be generated
//
// Return Value:
// None.
//
void Rationalizer::RewriteNodeAsCall(GenTreePtr* ppTree, Compiler::fgWalkData* data,
CORINFO_METHOD_HANDLE callHnd,
#ifdef FEATURE_READYTORUN_COMPILER
CORINFO_CONST_LOOKUP entryPoint,
#endif
GenTreeArgList* args)
{
GenTreePtr tree = *ppTree;
Compiler* comp = data->compiler;
SplitData* tmpState = (SplitData *)data->pCallbackData;
GenTreePtr root = tmpState->root;
GenTreePtr treeFirstNode = comp->fgGetFirstNode(tree);
GenTreePtr treeLastNode = tree;
GenTreePtr treePrevNode = treeFirstNode->gtPrev;
GenTreePtr treeNextNode = treeLastNode->gtNext;
// Create the call node
GenTreeCall* call = comp->gtNewCallNode(CT_USER_FUNC, callHnd, tree->gtType, args);
call = comp->fgMorphArgs(call);
call->CopyCosts(tree);
#ifdef FEATURE_READYTORUN_COMPILER
call->gtCall.gtEntryPoint = entryPoint;
#endif
// Replace "tree" with "call"
*ppTree = call;
// Rebuild the evaluation order.
comp->gtSetStmtInfo(root);
// Rebuild the execution order.
comp->fgSetTreeSeq(call, treePrevNode);
// Restore linear-order Prev and Next for "call".
if (treePrevNode)
{
treeFirstNode = comp->fgGetFirstNode(call);
treeFirstNode->gtPrev = treePrevNode;
treePrevNode->gtNext = treeFirstNode;
}
else
{
// Update the linear oder start of "root" if treeFirstNode
// appears to have replaced the original first node.
assert(treeFirstNode == root->gtStmt.gtStmtList);
root->gtStmt.gtStmtList = comp->fgGetFirstNode(call);
}
if (treeNextNode)
{
treeLastNode = call;
treeLastNode->gtNext = treeNextNode;
treeNextNode->gtPrev = treeLastNode;
}
comp->fgFixupIfCallArg(data->parentStack, tree, call);
// Propagate flags of "call" to its parents.
// 0 is current node, so start at 1
for (int i = 1; i < data->parentStack->Height(); i++)
{
GenTree *node = data->parentStack->Index(i);
node->gtFlags |= GTF_CALL;
node->gtFlags |= call->gtFlags & GTF_ALL_EFFECT;
}
// Since "tree" is replaced with "call", pop "tree" node (i.e the current node)
// and replace it with "call" on parent stack.
assert(data->parentStack->Top() == tree);
(void)data->parentStack->Pop();
data->parentStack->Push(call);
DBEXEC(TRUE, ValidateStatement(root, tmpState->block));
}
// RewriteIntrinsicAsUserCall : Rewrite an intrinsic operator as a GT_CALL to the original method.
//
// Arguments:
// ppTree - A pointer-to-a-pointer for the intrinsic node
// fgWalkData - A pointer to tree walk data providing the context
//
// Return Value:
// None.
//
// Some intrinsics, such as operation Sqrt, are rewritten back to calls, and some are not.
// The ones that are not being rewritten here must be handled in Codegen.
// Conceptually, the lower is the right place to do the rewrite. Keeping it in rationalization is
// mainly for throughput issue.
void Rationalizer::RewriteIntrinsicAsUserCall(GenTreePtr* ppTree, Compiler::fgWalkData* data)
{
GenTreePtr tree = *ppTree;
Compiler* comp = data->compiler;
GenTreeArgList* args;
assert(tree->OperGet() == GT_INTRINSIC);
if (tree->gtOp.gtOp2 == nullptr)
{
args = comp->gtNewArgList(tree->gtOp.gtOp1);
}
else
{
args = comp->gtNewArgList(tree->gtOp.gtOp1, tree->gtOp.gtOp2);
}
RewriteNodeAsCall(ppTree, data,
tree->gtIntrinsic.gtMethodHandle,
#ifdef FEATURE_READYTORUN_COMPILER
tree->gtIntrinsic.gtEntryPoint,
#endif
args);
}
// tree walker callback function that rewrites ASG and ADDR nodes
Compiler::fgWalkResult Rationalizer::SimpleTransformHelper(GenTree **ppTree, Compiler::fgWalkData *data)
{
GenTree *tree = *ppTree;
Compiler* comp = data->compiler;
SplitData *tmpState = (SplitData *) data->pCallbackData;
while (tree->OperGet() == GT_COMMA)
{
RewriteOneComma(ppTree, data);
tree = *ppTree;
}
if (tree->OperIsAssignment())
{
GenTree *lhs = tree->gtGetOp1();
GenTree *dataSrc = tree->gtGetOp2();
// the other assign ops should have already been rewritten to ASG
assert(tree->OperGet() == GT_ASG);
while (lhs->OperGet() == GT_COMMA)
{
RewriteOneComma(&(tree->gtOp.gtOp1), data);
lhs = tree->gtGetOp1();
}
switch (lhs->OperGet())
{
case GT_LCL_VAR:
case GT_LCL_FLD:
case GT_REG_VAR:
case GT_PHI_ARG:
MorphAsgIntoStoreLcl(tmpState->root->AsStmt(), tree);
tree->gtFlags &= ~GTF_REVERSE_OPS;
break;
case GT_IND:
{
GenTreeStoreInd *store = new(comp, GT_STOREIND) GenTreeStoreInd(lhs->TypeGet(), lhs->gtGetOp1(), dataSrc);
if (tree->IsReverseOp()) store->gtFlags |= GTF_REVERSE_OPS;
store->gtFlags |= (lhs->gtFlags & GTF_IND_FLAGS);
store->CopyCosts(tree);
JITDUMP("Rewriting GT_ASG(GT_IND, X) to GT_STOREIND(X):\n");
DISPTREE(store);
JITDUMP("\n");
// Snip out the old GT_IND node
GenTreePtr indPrev = lhs->gtPrev;
indPrev->gtNext = lhs->gtNext;
indPrev->gtNext->gtPrev = indPrev;
// Replace "tree" with "store"
*ppTree = store;
store->gtNext = tree->gtNext;
store->gtPrev = tree->gtPrev;
if (store->gtNext != nullptr)
store->gtNext->gtPrev = store;
assert (store->gtPrev != nullptr);
store->gtPrev->gtNext = store;
// Since "tree" is replaced with "store", pop "tree" node (i.e the current node)
// and replace it with "store" on parent stack.
assert(data->parentStack->Top() == tree);
(void)data->parentStack->Pop();
data->parentStack->Push(store);
JITDUMP("root:\n");
DISPTREE(tmpState->root);
JITDUMP("\n");
}
break;
case GT_CLS_VAR:
{
lhs->gtOper = GT_CLS_VAR_ADDR;
lhs->gtType = TYP_BYREF;
tree->gtOper = GT_STOREIND;
JITDUMP("Rewriting GT_ASG(GT_CLS_VAR, X) to GT_STOREIND(GT_CLS_VAR_ADDR, X):\n");
DISPTREE(tree);
JITDUMP("\n");
}
break;
default:
assert(!"unhandled op\n");
break;
}
}
else if (tree->OperGet() == GT_BOX)
{
// GT_BOX at this level just passes through so get rid of it
Compiler::fgSnipNode(tmpState->root->AsStmt(), tree);
*ppTree = tree->gtOp.gtOp1;
comp->fgFixupIfCallArg(data->parentStack, tree, *ppTree);
JITDUMP("Rewriting GT_BOX(X) to X:\n");
DISPTREE(*ppTree);
JITDUMP("\n");
return SimpleTransformHelper(ppTree, data);
}
else if (tree->gtOper == GT_ADDR)
{
GenTree *child = tree->gtOp.gtOp1;
if (child->IsLocal())
{
// We are changing the child from GT_LCL_VAR TO GT_LCL_VAR_ADDR.
// Therefore gtType of the child needs to be changed to a TYP_BYREF
#ifdef DEBUG
if (child->gtOper == GT_LCL_VAR)
{
JITDUMP("Rewriting GT_ADDR(GT_LCL_VAR) to GT_LCL_VAR_ADDR:\n");
}
else
{
assert(child->gtOper == GT_LCL_FLD);
JITDUMP("Rewriting GT_ADDR(GT_LCL_FLD) to GT_LCL_FLD_ADDR:\n");
}
#endif // DEBUG
Compiler::fgSnipNode(tmpState->root->AsStmt(), tree);
child->gtOper = addrForm(child->gtOper);
child->gtType = TYP_BYREF;
copyFlags(child, tree, GTF_ALL_EFFECT);
*ppTree = child;
}
else if (child->gtOper == GT_CLS_VAR)
{
Compiler::fgSnipNode(tmpState->root->AsStmt(), tree);
child->gtOper = GT_CLS_VAR_ADDR;
child->gtType = TYP_BYREF;
copyFlags(child, tree, GTF_ALL_EFFECT);
*ppTree = child;
JITDUMP("Rewriting GT_ADDR(GT_CLS_VAR) to GT_CLS_VAR_ADDR:\n");
}
else if (child->gtOper == GT_IND)
{
Compiler::fgSnipNode(tmpState->root->AsStmt(), tree);
Compiler::fgSnipNode(tmpState->root->AsStmt(), child);
*ppTree = child->gtOp.gtOp1;
JITDUMP("Rewriting GT_ADDR(GT_IND(X)) to X:\n");
}
comp->fgFixupIfCallArg(data->parentStack, tree, *ppTree);
DISPTREE(*ppTree);
JITDUMP("\n");
}
else if (tree->gtOper == GT_NOP
&& tree->gtOp.gtOp1)
{
// fgmorph sometimes inserts NOP nodes between def and use
// supposedly 'to prevent constant folding'
Compiler::fgSnipNode(tmpState->root->AsStmt(), tree);
*ppTree = tree->gtOp.gtOp1;
comp->fgFixupIfCallArg(data->parentStack, tree, *ppTree);
// Since GT_NOP(op1) is replaced with op1, pop GT_NOP node (i.e the current node)
// and replace it with op1 on parent stack.
(void)data->parentStack->Pop();
data->parentStack->Push(tree->gtOp.gtOp1);
JITDUMP("Rewriting GT_NOP(X) to X:\n");
DISPTREE(*ppTree);
JITDUMP("\n");
return SimpleTransformHelper(ppTree, data);
}
else if (tree->gtOper == GT_QMARK)
{
// only certain forms of qmarks are allowed
// qmark(conditionExpr, 1, 0) is equivalent to conditionExpr
GenTree* colonNode = tree->gtOp.gtOp2;
GenTree* thenNode = colonNode->AsColon()->ThenNode();
GenTree* elseNode = colonNode->AsColon()->ElseNode();
assert(thenNode->IsCnsIntOrI());
assert(elseNode->IsCnsIntOrI());
assert(thenNode->gtIntConCommon.IconValue() == 1);
assert(elseNode->gtIntConCommon.IconValue() == 0);
Compiler::fgSnipNode(tmpState->root->AsStmt(), elseNode);
Compiler::fgSnipNode(tmpState->root->AsStmt(), thenNode);
Compiler::fgSnipNode(tmpState->root->AsStmt(), colonNode);
Compiler::fgSnipNode(tmpState->root->AsStmt(), tree);
*ppTree = tree->gtOp.gtOp1;
(*ppTree)->gtFlags &= ~GTF_RELOP_QMARK;
comp->fgFixupIfCallArg(data->parentStack, tree, *ppTree);
JITDUMP("Rewriting GT_QMARK(conditionExpr, 1, 0) to conditionExpr:\n");
DISPTREE(*ppTree);
JITDUMP("\n");
}
#ifdef _TARGET_XARCH_
else if (tree->gtOper == GT_CLS_VAR)
{
// rewrite "clsvar" as [&clsvar] so indirs are explicit
tree->gtOper = GT_CLS_VAR_ADDR;
GenTree *ind = comp->gtNewOperNode(GT_IND, tree->TypeGet(), tree);
tree->gtType = TYP_BYREF;
ind->CopyCosts(tree);
tree->InsertAfterSelf(ind, tmpState->root->AsStmt());
*ppTree = ind;
comp->fgFixupIfCallArg(data->parentStack, tree, ind);
JITDUMP("Rewriting GT_CLS_VAR to GT_IND(GT_CLS_VAR_ADDR(GT_CLS_VAR)):\n");
DISPTREE(tmpState->root);
JITDUMP("\n");
}
#endif // _TARGET_XARCH_
else if ((tree->gtOper == GT_INTRINSIC) &&
Compiler::IsIntrinsicImplementedByUserCall(tree->gtIntrinsic.gtIntrinsicId))
{
RewriteIntrinsicAsUserCall(ppTree, data);
}
#ifdef FEATURE_SIMD
else
{
assert(tree->gtOper != GT_INTRINSIC || Compiler::IsTargetIntrinsic(tree->gtIntrinsic.gtIntrinsicId));
// Transform the treeNode types for SIMD nodes.
// If we have a SIMD type, set its size in simdSize, and later we will
// set the actual type according to its size (which may be less than a full
// vector register).
unsigned simdSize = 0;
switch(tree->gtOper)
{
default:
// Nothing to do for most nodes.
break;
case GT_INITBLK:
RewriteInitBlk(ppTree, data);
break;
case GT_COPYBLK:
RewriteCopyBlk(ppTree, data);
break;
case GT_LDOBJ:
RewriteLdObj(ppTree, data);
break;
case GT_LCL_FLD:
case GT_STORE_LCL_FLD:
FixupIfSIMDLocal(comp, tree->AsLclVarCommon());
break;
case GT_STOREIND:
case GT_IND:
if (tree->gtType == TYP_STRUCT)
{
GenTree* addr = tree->AsIndir()->Addr();
assert(addr->OperIsLocal() && addr->TypeGet() == TYP_BYREF);
LclVarDsc* varDsc = &(comp->lvaTable[addr->AsLclVarCommon()->gtLclNum]);
assert(varDsc->lvSIMDType);
simdSize = (unsigned int) roundUp(varDsc->lvExactSize, TARGET_POINTER_SIZE);
tree->gtType = comp->getSIMDTypeForSize(simdSize);
}
break;
case GT_SIMD:
{
noway_assert(comp->featureSIMD);
GenTreeSIMD* simdTree = (*ppTree)->AsSIMD();
simdSize = simdTree->gtSIMDSize;
var_types simdType = comp->getSIMDTypeForSize(simdSize);
// TODO-Cleanup: This is no-longer required once we plumb SIMD types thru front-end
if (simdTree->gtType == TYP_I_IMPL && simdTree->gtSIMDSize == TARGET_POINTER_SIZE)
{
// This happens when it is consumed by a GT_RET_EXPR.
// It can only be a Vector2f or Vector2i.
assert(genTypeSize(simdTree->gtSIMDBaseType) == 4);
simdTree->gtType = TYP_SIMD8;
}
else if (simdTree->gtType == TYP_STRUCT || varTypeIsSIMD(simdTree))
{
tree->gtType = simdType;
}
// Certain SIMD trees require rationalizing.
if (simdTree->gtSIMD.gtSIMDIntrinsicID == SIMDIntrinsicInitArray)
{
// Rewrite this as an explicit load.
JITDUMP("Rewriting GT_SIMD array init as an explicit load:\n");
unsigned int baseTypeSize = genTypeSize(simdTree->gtSIMDBaseType);
GenTree* address = new (comp, GT_LEA) GenTreeAddrMode(TYP_BYREF, simdTree->gtOp1, simdTree->gtOp2, baseTypeSize, offsetof(CORINFO_Array, u1Elems));
GenTree *ind = comp->gtNewOperNode(GT_IND, simdType, address);
address->CopyCosts(simdTree);
ind->CopyCosts(simdTree);
// Fix up the links.
GenTreePtr addressPrev = simdTree->gtPrev;
assert(addressPrev != nullptr);
GenTree* indNext = simdTree->gtNext;
// We don't have any top-level GT_SIMD nodes.
assert(addressPrev != nullptr);
address->gtPrev = addressPrev;
addressPrev->gtNext = address;
ind->gtPrev = address;
address->gtNext = ind;
indNext->gtPrev = ind;
ind->gtNext = indNext;
// Replace "simdTree" with "ind"
*ppTree = ind;
DISPTREE(tmpState->root);
JITDUMP("\n");
}
else
{
// This code depends on the fact that NONE of the SIMD intrinsics take vector operands
// of a different width. If that assumption changes, we will EITHER have to make these type
// transformations during importation, and plumb the types all the way through the JIT,
// OR add a lot of special handling here.
GenTree* op1 = simdTree->gtGetOp1();
if (op1 != nullptr && op1->gtType == TYP_STRUCT)
{
op1->gtType = simdType;
}
GenTree* op2 = simdTree->gtGetOp2();
if (op2 != nullptr && op2->gtType == TYP_STRUCT)
{
op2->gtType = simdType;
}
}
}
break;
}
if ((*ppTree) != tree)
{
return SimpleTransformHelper(ppTree, data);
}
}
#endif // FEATURE_SIMD
return Compiler::WALK_CONTINUE;
}
// FixupIfSIMDLocal: Fixup the type of a lclVar tree, as needed, if it is a SIMD type vector.
//
// Arguments:
// comp - the Compiler object.
// tree - the GenTreeLclVarCommon tree to be fixed up.
//
// Return Value:
// None.
//
// TODO-Cleanup: Once SIMD types are plumbed through the frontend, this will no longer
// be required.
void Rationalizer::FixupIfSIMDLocal(Compiler* comp, GenTreeLclVarCommon* tree)
{
#ifdef FEATURE_SIMD
if (!comp->featureSIMD)
{
return;
}
LclVarDsc* varDsc = &(comp->lvaTable[tree->gtLclNum]);
// Don't mark byref of SIMD vector as a SIMD type.
// Note that struct args though marked as lvIsSIMD=true,
// the tree node representing such an arg should not be
// marked as a SIMD type, since it is a byref of a SIMD type.
if (!varTypeIsSIMD(varDsc))
{
return;
}
switch(tree->OperGet())
{
default:
// Nothing to do for most tree nodes.
break;
case GT_LCL_FLD:
// We may see a lclFld used for pointer-sized structs that have been morphed, in which
// case we can change it to GT_LCL_VAR.
// However, we may also see a lclFld with FieldSeqStore::NotAField() for structs that can't
// be analyzed, e.g. those with overlapping fields such as the IL implementation of Vector<T>.
if ((tree->AsLclFld()->gtFieldSeq == FieldSeqStore::NotAField()) &&
(tree->AsLclFld()->gtLclOffs == 0) &&
(tree->gtType == TYP_I_IMPL) &&
(varDsc->lvExactSize == TARGET_POINTER_SIZE))
{
tree->SetOper(GT_LCL_VAR);
tree->gtFlags &= ~(GTF_VAR_USEASG);
}
else
{
// If we access a field of a SIMD lclVar via GT_LCL_FLD, it cannot have been
// independently promoted.
assert(comp->lvaGetPromotionType(varDsc) != Compiler::PROMOTION_TYPE_INDEPENDENT);
return;
}
break;
case GT_STORE_LCL_FLD:
assert(tree->gtType == TYP_I_IMPL);
tree->SetOper(GT_STORE_LCL_VAR);
tree->gtFlags &= ~(GTF_VAR_USEASG);
break;
}
unsigned simdSize = (unsigned int) roundUp(varDsc->lvExactSize, TARGET_POINTER_SIZE);
tree->gtType = comp->getSIMDTypeForSize(simdSize);
#endif // FEATURE_SIMD
}
#ifdef DEBUG
void Rationalizer::ValidateStatement(Location loc)
{
ValidateStatement(loc.tree, loc.block);
}
void Rationalizer::ValidateStatement(GenTree *tree, BasicBlock *block)
{
assert(tree->gtOper == GT_STMT);
DBEXEC(TRUE, GetTlsCompiler()->fgDebugCheckNodeLinks(block, tree));
}
// sanity checks that apply to all kinds of IR
void Rationalizer::SanityCheck()
{
BasicBlock * block;
foreach_block(comp, block)
{
for (GenTree* statement = block->bbTreeList;
statement != nullptr;
statement = statement->gtNext)
{
ValidateStatement(statement, block);
for (GenTree *tree = statement->gtStmt.gtStmtList;
tree;
tree = tree->gtNext)
{
if (tree->OperGet() == GT_ASG)
{
if (tree->gtGetOp1()->OperGet() == GT_LCL_VAR)
{
assert(tree->gtGetOp1()->gtFlags & GTF_VAR_DEF);
}
else if (tree->gtGetOp2()->OperGet() == GT_LCL_VAR)
{
assert(!(tree->gtGetOp2()->gtFlags & GTF_VAR_DEF));
}
}
}
}
}
}
void Rationalizer::SanityCheckRational()
{
// TODO-Cleanup : check that the tree is rational here
// then do normal checks
SanityCheck();
}
#endif // DEBUG
void Rationalizer::DoPhase()
{
DBEXEC(TRUE, SanityCheck());
comp->compCurBB = NULL;
comp->fgOrder = Compiler::FGOrderLinear;
// If the first block is BBF_INTERNAL, it is special. Zero-inits must be placed in
// this block, and it must fall through to the next block.
// If there is a question op in the block (as can be the case with a just-my-code helper)
// then the rationalizer will expand that to flow and break the fallthrough invariant.
// However, we need to still keep the zero-inits in the original block, so only split before
// the statement containing the qmark.
if (comp->fgFirstBB->bbFlags & BBF_INTERNAL)
{
BasicBlock* const block = comp->fgFirstBB;
for (GenTree* stmt = block->bbTreeList; stmt; stmt = stmt->gtNext)
{
GenTreePtr node;
foreach_treenode_execution_order(node, stmt)
{
if (node->gtOper == GT_QMARK)
{
BasicBlock* newBlock;
if (stmt == block->bbTreeList)
newBlock = comp->fgSplitBlockAtBeginning(comp->fgFirstBB);
else
newBlock = comp->fgSplitBlockAfterStatement(block, stmt);
newBlock->bbFlags &= ~BBF_INTERNAL;
}
}
}
}
use = hashBv::Create(this->comp); // is used
usedef = hashBv::Create(this->comp); // is used and then defined
rename = hashBv::Create(this->comp); // is used, defined and used again
unexp = hashBv::Create(this->comp); // is unexposed - there is a def in this tree before any uses
// break up the trees at side effects, etc
Location loc(comp->fgFirstBB);
while (loc.block)
{
RenameUpdatedVars(loc);
// If we have a top-level GT_COMMA(X, GT_NOP), replace it by X.
if (loc.tree->gtStmt.gtStmtExpr->OperGet() == GT_COMMA)
{
GenTree* commaStmt = loc.tree;
GenTree* commaOp = commaStmt->gtStmt.gtStmtExpr;
if (commaOp->gtGetOp2()->OperGet() == GT_NOP)
{
#ifdef DEBUG
if (comp->verbose)
{
printf("Replacing GT_COMMA(X, GT_NOP) by X\n");
comp->gtDispTree(commaOp);
printf("\n");
}
#endif // DEBUG
comp->fgSnipNode(commaStmt->AsStmt(), commaOp);
comp->fgDeleteTreeFromList(commaStmt->AsStmt(), commaOp->gtGetOp2());
commaStmt->gtStmt.gtStmtExpr = commaOp->gtGetOp1();
}
}
loc = loc.Next();
}
loc.Reset(comp);
while (loc.block)
{
loc = TreeTransformRationalization(loc);
loc = loc.Next();
}
DBEXEC(TRUE, SanityCheckRational());
comp->compRationalIRForm = true;
}
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