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Internals: Spacing change in prep for LifePost rewrite from branch. No functional change.

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This commit is contained in:
Wilson Snyder 2018-06-20 20:24:11 -04:00
parent 1fad055286
commit 2a5123f318
1 changed files with 66 additions and 72 deletions
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138
src/V3LifePost.cpp
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@ -18,13 +18,13 @@
// //
//************************************************************************* //*************************************************************************
// LIFE TRANSFORMATIONS: // LIFE TRANSFORMATIONS:
// Build control-flow graph with assignments and var usages // Build control-flow graph with assignments and var usages
// All modules: // All modules:
// Delete these // Delete these
// ASSIGN(Vdly, a) // ASSIGN(Vdly, a)
// ... {no reads or writes of a after the first write to Vdly} // ... {no reads or writes of a after the first write to Vdly}
// ... {no reads of a after the first write to Vdly} // ... {no reads of a after the first write to Vdly}
// ASSIGNPOST(Vdly,tmp) // ASSIGNPOST(Vdly,tmp)
// //
//************************************************************************* //*************************************************************************
@ -39,38 +39,33 @@
#include "V3Stats.h" #include "V3Stats.h"
#include "V3Ast.h" #include "V3Ast.h"
//######################################################################
// LifePost state, as a visitor of each AstNode
class LifePostBaseVisitor : public AstNVisitor {
protected:
VL_DEBUG_FUNC; // Declare debug()
};
//###################################################################### //######################################################################
// LifePost class functions // LifePost class functions
class LifePostElimVisitor : public LifePostBaseVisitor { class LifePostElimVisitor : public AstNVisitor {
private: private:
bool m_tracingCall; // Iterating into a CCall to a CFunc bool m_tracingCall; // Iterating into a CCall to a CFunc
// NODE STATE // NODE STATE
// INPUT: // INPUT:
// AstVarScope::user4p() -> AstVarScope*, If set, replace this varscope with specified new one // AstVarScope::user4p() -> AstVarScope*, If set, replace this varscope with specified new one
// STATE // STATE
// METHODS
VL_DEBUG_FUNC; // Declare debug()
// VISITORS // VISITORS
virtual void visit(AstVarRef* nodep) { virtual void visit(AstVarRef* nodep) {
AstVarScope* vscp = nodep->varScopep(); AstVarScope* vscp = nodep->varScopep();
if (!vscp) nodep->v3fatalSrc("Scope not assigned"); if (!vscp) nodep->v3fatalSrc("Scope not assigned");
if (AstVarScope* newvscp = (AstVarScope*)vscp->user4p()) { if (AstVarScope* newvscp = (AstVarScope*)vscp->user4p()) {
UINFO(9, " Replace "<<nodep<<" to "<<newvscp<<endl); UINFO(9, " Replace "<<nodep<<" to "<<newvscp<<endl);
AstVarRef* newrefp = new AstVarRef(nodep->fileline(), newvscp, nodep->lvalue()); AstVarRef* newrefp = new AstVarRef(nodep->fileline(), newvscp, nodep->lvalue());
nodep->replaceWith(newrefp); nodep->replaceWith(newrefp);
nodep->deleteTree(); VL_DANGLING(nodep); nodep->deleteTree(); VL_DANGLING(nodep);
} }
} }
virtual void visit(AstNodeModule* nodep) { virtual void visit(AstNodeModule* nodep) {
// Only track the top scopes, not lower level functions // Only track the top scopes, not lower level functions
if (nodep->isTop()) iterateChildren(nodep); if (nodep->isTop()) iterateChildren(nodep);
} }
virtual void visit(AstCCall* nodep) { virtual void visit(AstCCall* nodep) {
@ -86,7 +81,7 @@ private:
m_tracingCall = false; m_tracingCall = false;
iterateChildren(nodep); iterateChildren(nodep);
} }
virtual void visit(AstVar*) {} // Don't want varrefs under it virtual void visit(AstVar*) {} // Don't want varrefs under it
virtual void visit(AstNode* nodep) { virtual void visit(AstNode* nodep) {
iterateChildren(nodep); iterateChildren(nodep);
} }
@ -102,48 +97,49 @@ public:
//###################################################################### //######################################################################
// LifePost delay elimination // LifePost delay elimination
class LifePostDlyVisitor : public LifePostBaseVisitor { class LifePostDlyVisitor : public AstNVisitor {
private: private:
// NODE STATE // NODE STATE
// Cleared on entire tree // Cleared on entire tree
// AstVarScope::user() -> Sequence # of first vertex setting this var. // AstVarScope::user() -> Sequence # of first vertex setting this var.
// AstVarScope::user2() -> Sequence # of last consumption of this var // AstVarScope::user2() -> Sequence # of last consumption of this var
// AstVarScope::user4() -> AstVarScope*: Passed to LifePostElim to substitute this var // AstVarScope::user4() -> AstVarScope*: Passed to LifePostElim to substitute this var
AstUser1InUse m_inuser1; AstUser1InUse m_inuser1;
AstUser2InUse m_inuser2; AstUser2InUse m_inuser2;
AstUser4InUse m_inuser4; AstUser4InUse m_inuser4;
// STATE // STATE
uint32_t m_sequence; // Sequence number of assignments/varrefs uint32_t m_sequence; // Sequence number of assigns/varrefs,
V3Double0 m_statAssnDel; // Statistic tracking V3Double0 m_statAssnDel; // Statistic tracking
bool m_tracingCall; // Tracing a CCall to a CFunc bool m_tracingCall; // Currently tracing a CCall to a CFunc
// METHODS
VL_DEBUG_FUNC; // Declare debug()
// VISITORS // VISITORS
virtual void visit(AstTopScope* nodep) { virtual void visit(AstTopScope* nodep) {
AstNode::user1ClearTree(); // user1p() used on entire tree AstNode::user1ClearTree(); // user1p() used on entire tree
AstNode::user2ClearTree(); // user2p() used on entire tree AstNode::user2ClearTree(); // user2p() used on entire tree
AstNode::user4ClearTree(); // user4p() used on entire tree AstNode::user4ClearTree(); // user4p() used on entire tree
m_sequence = 0; m_sequence = 0;
iterateChildren(nodep); iterateChildren(nodep);
// Replace any node4p varscopes with the new scope // Replace any node4p varscopes with the new scope
LifePostElimVisitor visitor (nodep); LifePostElimVisitor visitor (nodep);
} }
virtual void visit(AstVarRef* nodep) { virtual void visit(AstVarRef* nodep) {
// Consumption/generation of a variable, // Consumption/generation of a variable,
AstVarScope* vscp = nodep->varScopep(); AstVarScope* vscp = nodep->varScopep();
if (!vscp) nodep->v3fatalSrc("Scope not assigned"); if (!vscp) nodep->v3fatalSrc("Scope not assigned");
m_sequence++; m_sequence++;
if (nodep->lvalue()) { if (nodep->lvalue()) {
// First generator // First generator
if (!vscp->user1()) vscp->user1(m_sequence); if (!vscp->user1()) vscp->user1(m_sequence);
} else { } else {
// Last consumer // Last consumer
vscp->user2(m_sequence); vscp->user2(m_sequence);
} }
} }
virtual void visit(AstAssignPre* nodep) { virtual void visit(AstAssignPre* nodep) {
// Do not record varrefs within assign pre. // Do not record varrefs within assign pre.
// //
@ -151,7 +147,6 @@ private:
// first write; we only want to consider reads and writes that // first write; we only want to consider reads and writes that
// would still happen if the dly var were eliminated. // would still happen if the dly var were eliminated.
} }
virtual void visit(AstAssignPost* nodep) { virtual void visit(AstAssignPost* nodep) {
if (AstVarRef* lhsp = VN_CAST(nodep->lhsp(), VarRef)) { if (AstVarRef* lhsp = VN_CAST(nodep->lhsp(), VarRef)) {
if (AstVarRef* rhsp = VN_CAST(nodep->rhsp(), VarRef)) { if (AstVarRef* rhsp = VN_CAST(nodep->rhsp(), VarRef)) {
@ -164,9 +159,9 @@ private:
// Into just this: // Into just this:
// X1: __PVT__q = __PVT__clk_clocks; // X1: __PVT__q = __PVT__clk_clocks;
// X2: (nothing) // X2: (nothing)
UINFO(9," POST "<<nodep<<endl); UINFO(9," POST "<<nodep<<endl);
UINFO(9," lhs "<<lhsp<<endl); UINFO(9," lhs "<<lhsp<<endl);
UINFO(9," rhs "<<rhsp<<endl); UINFO(9," rhs "<<rhsp<<endl);
uint32_t firstDlyVarWrite = rhsp->varScopep()->user1(); uint32_t firstDlyVarWrite = rhsp->varScopep()->user1();
uint32_t lastDlyVarRead = rhsp->varScopep()->user2(); uint32_t lastDlyVarRead = rhsp->varScopep()->user2();
uint32_t lastOrigVarRead = lhsp->varScopep()->user2(); uint32_t lastOrigVarRead = lhsp->varScopep()->user2();
@ -175,17 +170,17 @@ private:
<<" last_orig_r "<<lastOrigVarRead<<endl); <<" last_orig_r "<<lastOrigVarRead<<endl);
if (lastDlyVarRead < firstDlyVarWrite if (lastDlyVarRead < firstDlyVarWrite
&& lastOrigVarRead < firstDlyVarWrite) { && lastOrigVarRead < firstDlyVarWrite) {
UINFO(4," DELETE "<<nodep<<endl); UINFO(4," DELETE "<<nodep<<endl);
// Mark so LifePostElimVisitor will get it // Mark so LifePostElimVisitor will get it
rhsp->varScopep()->user4p(lhsp->varScopep()); rhsp->varScopep()->user4p(lhsp->varScopep());
nodep->unlinkFrBack()->deleteTree(); VL_DANGLING(nodep); nodep->unlinkFrBack()->deleteTree(); VL_DANGLING(nodep);
++m_statAssnDel; ++m_statAssnDel;
} }
} }
} }
} }
virtual void visit(AstNodeModule* nodep) { virtual void visit(AstNodeModule* nodep) {
// Only track the top scopes, not lower level functions // Only track the top scopes, not lower level functions
if (nodep->isTop()) iterateChildren(nodep); if (nodep->isTop()) iterateChildren(nodep);
} }
virtual void visit(AstCCall* nodep) { virtual void visit(AstCCall* nodep) {
@ -201,9 +196,8 @@ private:
m_tracingCall = false; m_tracingCall = false;
iterateChildren(nodep); iterateChildren(nodep);
} }
//----- //-----
virtual void visit(AstVar*) {} // Don't want varrefs under it virtual void visit(AstVar*) {} // Don't want varrefs under it
virtual void visit(AstNode* nodep) { virtual void visit(AstNode* nodep) {
iterateChildren(nodep); iterateChildren(nodep);
} }
@ -215,7 +209,7 @@ public:
iterate(nodep); iterate(nodep);
} }
virtual ~LifePostDlyVisitor() { virtual ~LifePostDlyVisitor() {
V3Stats::addStat("Optimizations, Lifetime postassign deletions", m_statAssnDel); V3Stats::addStat("Optimizations, Lifetime postassign deletions", m_statAssnDel);
} }
}; };
@ -226,7 +220,7 @@ void V3LifePost::lifepostAll(AstNetlist* nodep) {
UINFO(2,__FUNCTION__<<": "<<endl); UINFO(2,__FUNCTION__<<": "<<endl);
// Mark redundant AssignPost // Mark redundant AssignPost
{ {
LifePostDlyVisitor visitor (nodep); LifePostDlyVisitor visitor(nodep);
} // Destruct before checking } // Destruct before checking
V3Global::dumpCheckGlobalTree("life_post", 0, v3Global.opt.dumpTreeLevel(__FILE__) >= 3); V3Global::dumpCheckGlobalTree("life_post", 0, v3Global.opt.dumpTreeLevel(__FILE__) >= 3);
} }