verilator/src/V3Assert.cpp

907 lines
41 KiB
C++

// -*- mode: C++; c-file-style: "cc-mode" -*-
//*************************************************************************
// DESCRIPTION: Verilator: Collect and print statistics
//
// Code available from: https://verilator.org
//
//*************************************************************************
//
// Copyright 2005-2025 by Wilson Snyder. This program is free software; you
// can redistribute it and/or modify it under the terms of either the GNU
// Lesser General Public License Version 3 or the Perl Artistic License
// Version 2.0.
// SPDX-License-Identifier: LGPL-3.0-only OR Artistic-2.0
//
//*************************************************************************
#include "V3PchAstNoMT.h" // VL_MT_DISABLED_CODE_UNIT
#include "V3Assert.h"
#include "V3Stats.h"
VL_DEFINE_DEBUG_FUNCTIONS;
//######################################################################
// AssertDeFuture
// If any AstFuture, then move all non-future varrefs to be one cycle behind,
// see IEEE 1800-2023 16.9.4.
class AssertDeFuture final : public VNVisitor {
// STATE - across all visitors
AstNodeModule* const m_modp; // Module future is underneath
const AstFuture* m_futurep; // First AstFuture found
const unsigned m_pastNum; // Prefix unique number for this module
std::map<AstVar*, AstVar*> m_delayedVars; // Old to delayed variable mapping
// STATE - for current visit position (use VL_RESTORER)
bool m_inFuture = false; // Inside a future
bool m_unsupported = false; // Printed unsupported
// METHODS
void unsupported(AstNode* nodep) {
if (m_unsupported) return;
m_unsupported = true;
nodep->v3warn(E_UNSUPPORTED,
"Unsupported/illegal: Future value function used with expression with "
<< nodep->prettyOperatorName());
}
// VISITORS
void visit(AstFuture* nodep) override {
VL_RESTORER(m_inFuture);
m_inFuture = true;
iterateChildren(nodep);
// Done with the future, this subexpression is current-time
nodep->replaceWith(nodep->exprp()->unlinkFrBack());
VL_DO_DANGLING(pushDeletep(nodep), nodep);
}
void visit(AstNodeVarRef* nodep) override {
if (nodep->user1SetOnce()) return;
if (m_inFuture || m_unsupported)
return; // Need user1 set above, don't process when Future is removed
if (nodep->access().isWriteOrRW()) {
unsupported(nodep);
return;
}
auto it = m_delayedVars.find(nodep->varp());
AstVar* outvarp;
if (it == m_delayedVars.end()) {
AstSenTree* const sentreep = m_futurep->sentreep();
AstAlways* const alwaysp = new AstAlways{nodep->fileline(), VAlwaysKwd::ALWAYS,
sentreep->cloneTree(false), nullptr};
m_modp->addStmtsp(alwaysp);
outvarp = new AstVar{nodep->fileline(), VVarType::MODULETEMP,
"__Vnotfuture" + cvtToStr(m_pastNum) + "_" + nodep->name(),
nodep->dtypep()};
m_modp->addStmtsp(outvarp);
AstVarRef* varRefAWritep = new AstVarRef{nodep->fileline(), outvarp, VAccess::WRITE};
varRefAWritep->user1(true);
AstNodeVarRef* varRefAReadp = nodep->cloneTree(false);
varRefAReadp->user1(true);
AstNode* const assp = new AstAssignDly{nodep->fileline(), varRefAWritep, varRefAReadp};
alwaysp->addStmtsp(assp);
m_delayedVars.emplace(nodep->varp(), outvarp);
} else {
outvarp = it->second;
}
AstVarRef* newp = new AstVarRef{nodep->fileline(), outvarp, VAccess::READ};
newp->user1(true);
UINFO(9, "DeFuture " << nodep << " becomes " << newp);
nodep->replaceWith(newp);
VL_DO_DANGLING(pushDeletep(nodep), nodep);
}
void visit(AstNodeFTaskRef* nodep) override { unsupported(nodep); }
void visit(AstMethodCall* nodep) override { unsupported(nodep); }
void visit(AstNode* nodep) override {
if (!nodep->isPure()) unsupported(nodep);
iterateChildren(nodep);
}
public:
// CONSTRUCTORS
explicit AssertDeFuture(AstNode* nodep, AstNodeModule* modp, unsigned pastNum)
: m_modp{modp}
, m_pastNum{pastNum} {
// See if any Future before we process
if (nodep->forall([&](const AstFuture* futurep) -> bool {
m_futurep = futurep;
return false;
}))
return;
// UINFOTREE(9, nodep, "", "defuture-in");
visit(nodep); // Nodep may get deleted
// UINFOTREE(9, nodep, "", "defuture-ou");
}
~AssertDeFuture() = default;
};
//######################################################################
// AssertVisitor
class AssertVisitor final : public VNVisitor {
// CONSTANTS
static constexpr uint8_t ALL_ASSERT_TYPES
= std::numeric_limits<std::underlying_type<VAssertType::en>::type>::max();
// NODE STATE/TYPES
// Cleared on netlist
// AstNode::user1() -> bool. True if processed
const VNUser1InUse m_inuser1;
// STATE
AstNodeModule* m_modp = nullptr; // Last module
const AstNode* m_beginp = nullptr; // Last AstBegin/AstGenBlock
unsigned m_monitorNum = 0; // Global $monitor numbering (not per module)
AstVar* m_monitorNumVarp = nullptr; // $monitor number variable
AstVar* m_monitorOffVarp = nullptr; // $monitoroff variable
unsigned m_modPastNum = 0; // Module past numbering
unsigned m_modStrobeNum = 0; // Module $strobe numbering
const AstNodeProcedure* m_procedurep = nullptr; // Current procedure
VDouble0 m_statCover; // Statistic tracking
VDouble0 m_statAsNotImm; // Statistic tracking
VDouble0 m_statAsImm; // Statistic tracking
VDouble0 m_statAsFull; // Statistic tracking
VDouble0 m_statPastVars; // Statistic tracking
bool m_inSampled = false; // True inside a sampled expression
bool m_inRestrict = false; // True inside restrict assertion
AstNode* m_passsp = nullptr; // Current pass statement
AstNode* m_failsp = nullptr; // Current fail statement
bool m_underAssert = false; // Visited from assert
// METHODS
static AstNodeExpr* assertOnCond(FileLine* fl, VAssertType type,
VAssertDirectiveType directiveType) {
// cppcheck-suppress missingReturn
switch (directiveType) {
case VAssertDirectiveType::INTRINSIC: return new AstConst{fl, AstConst::BitTrue{}};
case VAssertDirectiveType::VIOLATION_CASE: {
if (v3Global.opt.assertCase()) {
return new AstCExpr{fl, AstCExpr::Pure{}, "vlSymsp->_vm_contextp__->assertOn()",
1};
}
// If assertions are off, have constant propagation rip them out later
// This allows syntax errors and such to be detected normally.
return new AstConst{fl, AstConst::BitFalse{}};
}
case VAssertDirectiveType::ASSERT:
case VAssertDirectiveType::COVER:
case VAssertDirectiveType::ASSUME: {
if (v3Global.opt.assertOn()) {
return new AstCExpr{fl, AstCExpr::Pure{},
"vlSymsp->_vm_contextp__->assertOnGet("s + std::to_string(type)
+ ", "s + std::to_string(directiveType) + ")"s,
1};
}
return new AstConst{fl, AstConst::BitFalse{}};
}
case VAssertDirectiveType::INTERNAL:
case VAssertDirectiveType::VIOLATION_IF:
case VAssertDirectiveType::RESTRICT: {
if (v3Global.opt.assertOn()) {
return new AstCExpr{fl, AstCExpr::Pure{}, "vlSymsp->_vm_contextp__->assertOn()",
1};
}
return new AstConst{fl, AstConst::BitFalse{}};
}
}
VL_UNREACHABLE;
}
string assertDisplayMessage(const AstNode* nodep, const string& prefix, const string& message,
VDisplayType severity) {
if (severity == VDisplayType::DT_ERROR || severity == VDisplayType::DT_FATAL) {
return ("[%0t] "s + prefix + ": " + nodep->fileline()->filebasename() + ":"
+ cvtToStr(nodep->fileline()->lineno()) + ": Assertion failed in %m"
+ ((message != "") ? ": " : "") + message + "\n");
} else {
return ("[%0t] "s + prefix + ": " + nodep->fileline()->filebasename() + ":"
+ cvtToStr(nodep->fileline()->lineno()) + ": %m"
+ ((message != "") ? ": " : "") + message + "\n");
}
}
static bool resolveAssertType(AstAssertCtl* nodep) {
if (!nodep->assertTypesp()) {
nodep->ctlAssertTypes(VAssertType{ALL_ASSERT_TYPES});
return true;
}
if (const AstConst* const assertTypesp = VN_CAST(nodep->assertTypesp(), Const)) {
nodep->ctlAssertTypes(VAssertType{assertTypesp->toSInt()});
return true;
}
return false;
}
static bool resolveControlType(AstAssertCtl* nodep) {
if (const AstConst* const constp = VN_CAST(nodep->controlTypep(), Const)) {
nodep->ctlType(constp->toSInt());
return true;
}
return false;
}
static bool resolveDirectiveType(AstAssertCtl* nodep) {
if (!nodep->directiveTypesp()) {
nodep->ctlDirectiveTypes(VAssertDirectiveType::ASSERT | VAssertDirectiveType::ASSUME
| VAssertDirectiveType::COVER);
return true;
}
if (const AstConst* const directiveTypesp = VN_CAST(nodep->directiveTypesp(), Const)) {
nodep->ctlDirectiveTypes(VAssertDirectiveType{directiveTypesp->toSInt()});
return true;
}
return false;
}
void replaceDisplay(AstDisplay* nodep, const string& prefix) {
nodep->fmtp()->text(
assertDisplayMessage(nodep, prefix, nodep->fmtp()->text(), nodep->displayType()));
nodep->displayType(VDisplayType::DT_WRITE);
// cppcheck-suppress nullPointer
AstNodeExpr* const timenewp = new AstTime{nodep->fileline(), m_modp->timeunit()};
if (AstNodeExpr* const timesp = nodep->fmtp()->exprsp()) {
timesp->unlinkFrBackWithNext();
timenewp->addNext(timesp);
}
nodep->fmtp()->addExprsp(timenewp);
if (!nodep->fmtp()->scopeNamep() && nodep->fmtp()->formatScopeTracking()) {
nodep->fmtp()->scopeNamep(new AstScopeName{nodep->fileline(), true});
}
}
AstSampled* newSampledExpr(AstNodeExpr* nodep) {
AstSampled* const sampledp = new AstSampled{nodep->fileline(), nodep};
sampledp->dtypeFrom(nodep);
return sampledp;
}
AstVarRef* newMonitorNumVarRefp(const AstNode* nodep, VAccess access) {
if (!m_monitorNumVarp) {
m_monitorNumVarp = new AstVar{nodep->fileline(), VVarType::MODULETEMP, "__VmonitorNum",
nodep->findUInt64DType()};
v3Global.rootp()->dollarUnitPkgAddp()->addStmtsp(m_monitorNumVarp);
}
AstVarRef* const varrefp = new AstVarRef{nodep->fileline(), m_monitorNumVarp, access};
varrefp->classOrPackagep(v3Global.rootp()->dollarUnitPkgAddp());
return varrefp;
}
AstVarRef* newMonitorOffVarRefp(const AstNode* nodep, VAccess access) {
if (!m_monitorOffVarp) {
m_monitorOffVarp = new AstVar{nodep->fileline(), VVarType::MODULETEMP, "__VmonitorOff",
nodep->findBitDType()};
v3Global.rootp()->dollarUnitPkgAddp()->addStmtsp(m_monitorOffVarp);
}
AstVarRef* const varrefp = new AstVarRef{nodep->fileline(), m_monitorOffVarp, access};
varrefp->classOrPackagep(v3Global.rootp()->dollarUnitPkgAddp());
return varrefp;
}
static AstNodeStmt* newIfAssertOn(AstNode* bodyp, VAssertDirectiveType directiveType,
VAssertType type = VAssertType::INTERNAL) {
// Add a internal if to check assertions are on.
// Don't make this a AND term, as it's unlikely to need to test this.
FileLine* const fl = bodyp->fileline();
AstNodeExpr* const condp = assertOnCond(fl, type, directiveType);
AstNodeIf* const newp = new AstIf{fl, condp, bodyp};
newp->isBoundsCheck(true); // To avoid LATCH warning
newp->user1(true); // Don't assert/cover this if
return newp;
}
static AstIf* assertCond(AstNodeCoverOrAssert* nodep, AstNodeExpr* propp, AstNode* passsp,
AstNode* failsp) {
AstIf* const ifp = new AstIf{nodep->fileline(), propp, passsp, failsp};
// It's more LIKELY that we'll take the nullptr if clause
// than the sim-killing else clause:
ifp->branchPred(VBranchPred::BP_LIKELY);
ifp->isBoundsCheck(true); // To avoid LATCH warning
return ifp;
}
AstNode* assertBody(AstNodeCoverOrAssert* nodep, AstNode* propp, AstNode* passsp,
AstNode* failsp) {
AstNode* bodyp = nullptr;
if (AstPExpr* const pexprp = VN_CAST(propp, PExpr)) {
AstFork* const forkp = new AstFork{nodep->fileline(), VJoinType::JOIN_NONE};
forkp->addForksp(pexprp->bodyp()->unlinkFrBack());
VL_DO_DANGLING(pushDeletep(pexprp), pexprp);
bodyp = forkp;
} else {
bodyp = assertCond(nodep, VN_AS(propp, NodeExpr), passsp, failsp);
}
return newIfAssertOn(bodyp, nodep->directive(), nodep->type());
}
AstNodeStmt* newFireAssertUnchecked(const AstNodeStmt* nodep, const string& message,
AstNodeExpr* exprsp = nullptr) {
// Like newFireAssert() but omits the asserts-on check
AstDisplay* const dispp
= new AstDisplay{nodep->fileline(), VDisplayType::DT_ERROR, message, nullptr, nullptr};
dispp->fmtp()->timeunit(m_modp->timeunit());
AstNodeStmt* const bodysp = dispp;
replaceDisplay(dispp, "%%Error"); // Convert to standard DISPLAY format
if (exprsp) dispp->fmtp()->exprsp()->addNext(exprsp);
if (v3Global.opt.stopFail()) bodysp->addNext(new AstStop{nodep->fileline(), false});
return bodysp;
}
AstNodeStmt* newFireAssert(const AstNodeStmt* nodep, VAssertDirectiveType directiveType,
VAssertType assertType, const string& message,
AstNodeExpr* exprsp = nullptr) {
AstNodeStmt* bodysp = newFireAssertUnchecked(nodep, message, exprsp);
bodysp = newIfAssertOn(bodysp, directiveType, assertType);
return bodysp;
}
void visitAssertionIterate(AstNodeCoverOrAssert* nodep, AstNode* failsp) {
if (m_beginp && nodep->name() == "") nodep->name(m_beginp->name());
{ AssertDeFuture{nodep->propp(), m_modp, m_modPastNum++}; }
iterateChildren(nodep);
AstSenTree* const sentreep = nodep->sentreep();
const string& message = nodep->name();
AstNode* passsp = nodep->passsp();
if (passsp) passsp->unlinkFrBackWithNext();
if (failsp) failsp->unlinkFrBackWithNext();
if (nodep->immediate()) {
UASSERT_OBJ(!sentreep, nodep, "Immediate assertions don't have sensitivity");
} else {
UASSERT_OBJ(sentreep, nodep, "Concurrent assertions must have sensitivity");
sentreep->unlinkFrBack();
if (m_procedurep) {
// To support this need queue of asserts to activate
nodep->v3warn(E_UNSUPPORTED,
"Unsupported: Procedural concurrent assertion with"
" clocking event inside always (IEEE 1800-2023 16.14.6)");
}
}
//
bool selfDestruct = false;
if (const AstCover* const snodep = VN_CAST(nodep, Cover)) {
++m_statCover;
if (!v3Global.opt.coverageUser()) {
selfDestruct = true;
} else {
// V3Coverage assigned us a bucket to increment.
AstCoverInc* const covincp = VN_AS(snodep->coverincsp(), CoverInc);
UASSERT_OBJ(covincp, snodep, "Missing AstCoverInc under assertion");
covincp->unlinkFrBackWithNext(); // next() might have AstAssign for trace
if (message != "") covincp->declp()->comment(message);
if (passsp) {
passsp = AstNode::addNext<AstNode, AstNode>(covincp, passsp);
} else {
passsp = covincp;
}
}
} else if (VN_IS(nodep, Assert) || VN_IS(nodep, AssertIntrinsic)) {
if (nodep->immediate()) {
++m_statAsImm;
} else {
++m_statAsNotImm;
}
if (!passsp && !failsp) failsp = newFireAssertUnchecked(nodep, "'assert' failed.");
} else {
nodep->v3fatalSrc("Unknown node type");
}
VL_RESTORER(m_passsp);
VL_RESTORER(m_failsp);
VL_RESTORER(m_underAssert);
m_passsp = passsp;
m_failsp = failsp;
m_underAssert = true;
iterate(nodep->propp());
AstNode* bodysp = assertBody(nodep, nodep->propp()->unlinkFrBack(), passsp, failsp);
if (sentreep) {
bodysp = new AstAlways{nodep->fileline(), VAlwaysKwd::ALWAYS, sentreep, bodysp};
}
if (passsp && !passsp->backp()) VL_DO_DANGLING(pushDeletep(passsp), passsp);
if (failsp && !failsp->backp()) VL_DO_DANGLING(pushDeletep(failsp), failsp);
// Install it
if (selfDestruct) {
// Delete it after making the tree. This way we can tell the user
// if it wasn't constructed nicely or has other errors without needing --coverage.
VL_DO_DANGLING(bodysp->deleteTree(), bodysp);
nodep->unlinkFrBack();
} else {
nodep->replaceWith(bodysp);
}
// Bye
VL_DO_DANGLING(pushDeletep(nodep), nodep);
}
// VISITORS
void visit(AstIf* nodep) override {
if (nodep->user1SetOnce()) return;
if (nodep->uniquePragma() || nodep->unique0Pragma()) {
const AstNodeIf* ifp = nodep;
AstNodeExpr* propp = nullptr;
bool hasDefaultElse = false;
do {
// If this statement ends with 'else if', then nextIf will point to the
// nextIf statement. Otherwise it will be null.
const AstNodeIf* const nextifp = dynamic_cast<AstNodeIf*>(ifp->elsesp());
iterateAndNextNull(ifp->condp());
// Recurse into the true case.
iterateAndNextNull(ifp->thensp());
// If the last else is not an else if, recurse into that too.
if (ifp->elsesp() && !nextifp) { //
iterateAndNextNull(ifp->elsesp());
}
// Build a bitmask of the true predicates
AstNodeExpr* const predp = ifp->condp()->cloneTreePure(false);
if (propp) {
propp = new AstConcat{nodep->fileline(), predp, propp};
} else {
propp = predp;
}
// Record if this ends with an 'else' that does not have an if
if (ifp->elsesp() && !nextifp) hasDefaultElse = true;
ifp = nextifp;
} while (ifp);
AstIf* const newifp = nodep->cloneTree(false);
const bool allow_none = nodep->unique0Pragma();
// Empty case means no property
if (!propp) propp = new AstConst{nodep->fileline(), AstConst::BitFalse{}};
// Note: if this ends with an 'else', then we don't need to validate that one of the
// predicates evaluates to true.
AstNodeExpr* const ohot
= ((allow_none || hasDefaultElse)
? static_cast<AstNodeExpr*>(new AstOneHot0{nodep->fileline(), propp})
: static_cast<AstNodeExpr*>(new AstOneHot{nodep->fileline(), propp}));
const VAssertType assertType
= nodep->uniquePragma() ? VAssertType::UNIQUE : VAssertType::UNIQUE0;
AstIf* const checkifp
= new AstIf{nodep->fileline(), new AstLogNot{nodep->fileline(), ohot},
newFireAssert(nodep, VAssertDirectiveType::VIOLATION_IF, assertType,
"'unique if' statement violated"),
newifp};
checkifp->isBoundsCheck(true); // To avoid LATCH warning
checkifp->branchPred(VBranchPred::BP_UNLIKELY);
nodep->replaceWith(checkifp);
VL_DO_DANGLING(pushDeletep(nodep), nodep);
} else {
iterateChildren(nodep);
}
}
//========== Case assertions
void visit(AstCase* nodep) override {
iterateChildren(nodep);
if (!nodep->user1SetOnce()) {
bool has_default = false;
for (AstCaseItem* itemp = nodep->itemsp(); itemp;
itemp = VN_AS(itemp->nextp(), CaseItem)) {
if (itemp->isDefault()) has_default = true;
}
const AstNodeDType* exprDtypep = nodep->exprp()->dtypep()->skipRefp();
VAssertType assertType = VAssertType::INTERNAL;
if (nodep->priorityPragma()) {
assertType = VAssertType::PRIORITY;
} else if (nodep->uniquePragma()) {
assertType = VAssertType::UNIQUE;
} else if (nodep->unique0Pragma()) {
assertType = VAssertType::UNIQUE0;
}
string valFmt;
if (exprDtypep->isIntegralOrPacked())
valFmt = " for '" + cvtToStr(exprDtypep->widthMin()) + "'h%X'";
if (nodep->fullPragma() || nodep->priorityPragma()) {
// Need to add a default if there isn't one already
++m_statAsFull;
if (!has_default) {
nodep->addItemsp(new AstCaseItem{
nodep->fileline(), nullptr /*DEFAULT*/,
newFireAssert(nodep, VAssertDirectiveType::VIOLATION_CASE, assertType,
nodep->pragmaString() + ", but non-match found" + valFmt,
valFmt.empty() ? nullptr
: nodep->exprp()->cloneTreePure(false))});
}
}
if (nodep->parallelPragma() || nodep->uniquePragma() || nodep->unique0Pragma()) {
// Need to check that one, and only one of the case items match at any moment
// If there's a default, we allow none to match, else exactly one must match
++m_statAsFull;
if (!has_default && !nodep->itemsp()) {
// Not parallel, but harmlessly so.
} else {
AstNodeExpr* propp = nullptr;
for (AstCaseItem* itemp = nodep->itemsp(); itemp;
itemp = VN_AS(itemp->nextp(), CaseItem)) {
for (AstNodeExpr* icondp = itemp->condsp(); icondp;
icondp = VN_AS(icondp->nextp(), NodeExpr)) {
AstNodeExpr* onep;
if (AstInsideRange* const rcondp = VN_CAST(icondp, InsideRange)) {
onep = rcondp->newAndFromInside(
nodep->exprp()->cloneTreePure(true),
rcondp->lhsp()->cloneTreePure(true),
rcondp->rhsp()->cloneTreePure(true));
} else if (nodep->casex() || nodep->casez() || nodep->caseInside()) {
onep = AstEqWild::newTyped(itemp->fileline(),
nodep->exprp()->cloneTreePure(false),
icondp->cloneTreePure(false));
} else {
onep = AstEq::newTyped(icondp->fileline(),
nodep->exprp()->cloneTreePure(false),
icondp->cloneTreePure(false));
}
if (propp) {
propp = new AstConcat{icondp->fileline(), onep, propp};
} else {
propp = onep;
}
}
}
// Empty case means no property
if (!propp) propp = new AstConst{nodep->fileline(), AstConst::BitFalse{}};
const bool allow_none = has_default || nodep->unique0Pragma();
// The following assertion lools as below.
// if (!$onehot(propp)) begin
// if (propp == '0) begin if (!allow_none) $error("none match"); end
// else $error("multiple match");
// end
AstNodeExpr* const ohot = new AstOneHot{nodep->fileline(), propp};
AstConst* const zero = new AstConst{
nodep->fileline(), AstConst::WidthedValue{}, propp->width(), 0};
AstIf* const ohotIfp
= new AstIf{nodep->fileline(), new AstLogNot{nodep->fileline(), ohot}};
AstIf* const zeroIfp = new AstIf{
nodep->fileline(),
new AstEq{nodep->fileline(), propp->cloneTreePure(false), zero}};
AstNodeExpr* const exprp = nodep->exprp();
const string pragmaStr = nodep->pragmaString();
if (!allow_none)
zeroIfp->addThensp(
newFireAssert(nodep, VAssertDirectiveType::VIOLATION_CASE, assertType,
pragmaStr + ", but none matched" + valFmt,
valFmt.empty() ? nullptr : exprp->cloneTreePure(false)));
zeroIfp->addElsesp(
newFireAssert(nodep, VAssertDirectiveType::VIOLATION_CASE, assertType,
pragmaStr + ", but multiple matches found" + valFmt,
valFmt.empty() ? nullptr : exprp->cloneTreePure(false)));
ohotIfp->addThensp(zeroIfp);
ohotIfp->isBoundsCheck(true); // To avoid LATCH warning
ohotIfp->branchPred(VBranchPred::BP_UNLIKELY);
nodep->addNotParallelp(ohotIfp);
}
}
}
}
void visit(AstFuture* nodep) override {
nodep->v3error("Future sampled value function called outside property or sequence "
"expression (IEEE 16.9.4)");
nodep->replaceWith(new AstConst{nodep->fileline(), 0});
VL_DO_DANGLING(pushDeletep(nodep), nodep);
}
//========== Past
void visit(AstPast* nodep) override {
iterateChildren(nodep);
uint32_t ticks = 1;
if (nodep->ticksp()) {
UASSERT_OBJ(VN_IS(nodep->ticksp(), Const), nodep,
"Expected constant ticks, checked in V3Width");
ticks = VN_AS(nodep->ticksp(), Const)->toUInt();
}
UASSERT_OBJ(ticks >= 1, nodep, "0 tick should have been checked in V3Width");
AstNodeExpr* const exprp = nodep->exprp()->unlinkFrBack();
AstNodeExpr* inp = newSampledExpr(exprp);
AstVar* invarp = nullptr;
AstSenTree* const sentreep = nodep->sentreep()->unlinkFrBack();
AstAlways* const alwaysp
= new AstAlways{nodep->fileline(), VAlwaysKwd::ALWAYS, sentreep, nullptr};
m_modp->addStmtsp(alwaysp);
for (uint32_t i = 0; i < ticks; ++i) {
// TODO recognize AstVarRef is getting delayed and share variables between
// $pasts with same reference (or same expression). Saves downstream
// optimizations from identifying and removing duplication.
AstVar* const outvarp = new AstVar{
nodep->fileline(), VVarType::MODULETEMP,
"_Vpast_" + cvtToStr(m_modPastNum++) + "_" + cvtToStr(i), inp->dtypep()};
outvarp->lifetime(VLifetime::AUTOMATIC_EXPLICIT);
++m_statPastVars;
m_modp->addStmtsp(outvarp);
AstNode* const assp = new AstAssignDly{
nodep->fileline(), new AstVarRef{nodep->fileline(), outvarp, VAccess::WRITE}, inp};
alwaysp->addStmtsp(assp);
// UINFOTREE(9, assp, "", "ass");
invarp = outvarp;
inp = new AstVarRef{nodep->fileline(), invarp, VAccess::READ};
}
nodep->replaceWith(inp);
VL_DO_DANGLING(pushDeletep(nodep), nodep);
}
//========== Move $sampled down to read-only variables
void visit(AstSampled* nodep) override {
if (nodep->user1()) return;
VL_RESTORER(m_inSampled);
{
m_inSampled = true;
iterateChildren(nodep);
}
nodep->replaceWith(nodep->exprp()->unlinkFrBack());
VL_DO_DANGLING(pushDeletep(nodep), nodep);
}
void visit(AstVarRef* nodep) override {
iterateChildren(nodep);
if (m_inSampled && !VString::startsWith(nodep->name(), "__VcycleDly")) {
if (!nodep->access().isReadOnly()) {
nodep->v3warn(E_UNSUPPORTED,
"Unsupported: Write to variable in sampled expression");
} else {
VNRelinker relinkHandle;
nodep->unlinkFrBack(&relinkHandle);
AstSampled* const newp = newSampledExpr(nodep);
relinkHandle.relink(newp);
newp->user1(1);
v3Global.setHasSampled();
}
}
}
// Don't sample sensitivities
void visit(AstSenItem* nodep) override {
VL_RESTORER(m_inSampled);
m_inSampled = false;
iterateChildren(nodep);
}
void visit(AstPExprClause* nodep) override {
if (m_underAssert) {
if (nodep->pass() && m_passsp) {
// Cover adds COVERINC by AstNode::addNext, thus need to clone next too.
nodep->replaceWith(m_passsp->cloneTree(true));
} else if (!nodep->pass() && m_failsp) {
// Asserts with multiple statements are wrapped in implicit begin/end blocks so no
// need to clone next.
nodep->replaceWith(m_failsp->cloneTree(false));
} else {
nodep->unlinkFrBack();
}
VL_DO_DANGLING(pushDeletep(nodep), nodep);
}
}
void visit(AstPExpr* nodep) override {
if (m_underAssert) {
VL_RESTORER(m_inSampled);
m_inSampled = false;
iterateChildren(nodep);
} else if (m_inRestrict) {
VL_DO_DANGLING(pushDeletep(nodep->unlinkFrBack()), nodep);
}
}
//========== Statements
void visit(AstDisplay* nodep) override {
iterateChildren(nodep);
// Replace the special types with standard text
if (nodep->displayType() == VDisplayType::DT_INFO) {
replaceDisplay(nodep, "-Info");
} else if (nodep->displayType() == VDisplayType::DT_WARNING) {
replaceDisplay(nodep, "%%Warning");
} else if (nodep->displayType() == VDisplayType::DT_ERROR) {
replaceDisplay(nodep, "%%Error");
} else if (nodep->displayType() == VDisplayType::DT_FATAL) {
replaceDisplay(nodep, "%%Fatal");
} else if (nodep->displayType() == VDisplayType::DT_MONITOR) {
nodep->displayType(VDisplayType::DT_DISPLAY);
FileLine* const fl = nodep->fileline();
AstNode* monExprsp = nodep->fmtp()->exprsp();
AstSenItem* monSenItemsp = nullptr;
while (monExprsp) {
if (AstNodeVarRef* varrefp = VN_CAST(monExprsp, NodeVarRef)) {
AstSenItem* const senItemp
= new AstSenItem{fl, VEdgeType::ET_CHANGED,
// Clone so get VarRef or VarXRef as needed
varrefp->cloneTree(false)};
if (!monSenItemsp) {
monSenItemsp = senItemp;
} else {
monSenItemsp->addNext(senItemp);
}
}
monExprsp = monExprsp->nextp();
}
AstSenTree* const monSenTree = new AstSenTree{fl, monSenItemsp};
const auto monNum = ++m_monitorNum;
// Where $monitor was we do "__VmonitorNum = N;"
AstAssign* const newsetp = new AstAssign{
fl, newMonitorNumVarRefp(nodep, VAccess::WRITE), new AstConst{fl, monNum}};
nodep->replaceWith(newsetp);
// Add "always_comb if (__VmonitorOn && __VmonitorNum==N) $display(...);"
AstNode* const stmtsp = nodep;
AstIf* const ifp = new AstIf{
fl,
new AstLogAnd{fl, new AstLogNot{fl, newMonitorOffVarRefp(nodep, VAccess::READ)},
new AstEq{fl, new AstConst{fl, monNum},
newMonitorNumVarRefp(nodep, VAccess::READ)}},
stmtsp};
ifp->isBoundsCheck(true); // To avoid LATCH warning
ifp->branchPred(VBranchPred::BP_UNLIKELY);
AstNode* const newp = new AstAlways{fl, VAlwaysKwd::ALWAYS, monSenTree, ifp};
m_modp->addStmtsp(newp);
} else if (nodep->displayType() == VDisplayType::DT_STROBE) {
nodep->displayType(VDisplayType::DT_DISPLAY);
// Need one-shot
FileLine* const fl = nodep->fileline();
AstVar* const varp
= new AstVar{fl, VVarType::MODULETEMP, "__Vstrobe" + cvtToStr(m_modStrobeNum++),
nodep->findBitDType()};
m_modp->addStmtsp(varp);
// Where $strobe was we do "__Vstrobe = '1;"
AstAssign* const newsetp = new AstAssign{fl, new AstVarRef{fl, varp, VAccess::WRITE},
new AstConst{fl, AstConst::BitTrue{}}};
nodep->replaceWith(newsetp);
// Add "always_comb if (__Vstrobe) begin $display(...); __Vstrobe = '0; end"
AstNode* const stmtsp = nodep;
AstIf* const ifp = new AstIf{fl, new AstVarRef{fl, varp, VAccess::READ}, stmtsp};
ifp->isBoundsCheck(true); // To avoid LATCH warning
ifp->branchPred(VBranchPred::BP_UNLIKELY);
AstNode* const newp = new AstAlwaysPostponed{fl, ifp};
stmtsp->addNext(new AstAssign{fl, new AstVarRef{fl, varp, VAccess::WRITE},
new AstConst{fl, AstConst::BitFalse{}}});
m_modp->addStmtsp(newp);
}
}
void visit(AstMonitorOff* nodep) override {
AstAssign* const newp
= new AstAssign{nodep->fileline(), newMonitorOffVarRefp(nodep, VAccess::WRITE),
new AstConst{nodep->fileline(), AstConst::BitTrue{}, nodep->off()}};
nodep->replaceWith(newp);
VL_DO_DANGLING(pushDeletep(nodep), nodep);
}
void visit(AstAssert* nodep) override { //
visitAssertionIterate(nodep, nodep->failsp());
}
void visit(AstAssertCtl* nodep) override {
if (VN_IS(m_modp, Class) || VN_IS(m_modp, Iface)) {
nodep->v3warn(E_UNSUPPORTED, "Unsupported: assertcontrols in classes or interfaces");
VL_DO_DANGLING(pushDeletep(nodep->unlinkFrBack()), nodep);
return;
}
iterateChildren(nodep);
if (!resolveAssertType(nodep)) {
nodep->v3warn(E_UNSUPPORTED,
"Unsupported: non-constant assert assertion-type expression");
VL_DO_DANGLING(pushDeletep(nodep->unlinkFrBack()), nodep);
return;
}
if (nodep->ctlAssertTypes() != ALL_ASSERT_TYPES
&& nodep->ctlAssertTypes().containsAny(VAssertType::EXPECT | VAssertType::UNIQUE
| VAssertType::UNIQUE0
| VAssertType::PRIORITY)) {
nodep->v3warn(E_UNSUPPORTED, "Unsupported: assert control assertion_type");
VL_DO_DANGLING(pushDeletep(nodep->unlinkFrBack()), nodep);
return;
}
if (!resolveControlType(nodep)) {
nodep->v3warn(E_UNSUPPORTED, "Unsupported: non-const assert control type expression");
VL_DO_DANGLING(pushDeletep(nodep->unlinkFrBack()), nodep);
return;
}
if (!resolveDirectiveType(nodep)) {
nodep->v3warn(E_UNSUPPORTED,
"Unsupported: non-const assert directive type expression");
VL_DO_DANGLING(pushDeletep(nodep->unlinkFrBack()), nodep);
return;
}
FileLine* const fl = nodep->fileline();
switch (nodep->ctlType()) {
case VAssertCtlType::ON:
UINFO(9, "Generating assertctl for a module: " << m_modp);
nodep->replaceWith(new AstCExpr{
fl,
"vlSymsp->_vm_contextp__->assertOnSet("s + std::to_string(nodep->ctlAssertTypes())
+ ", "s + std::to_string(nodep->ctlDirectiveTypes()) + ");\n"s,
1});
break;
case VAssertCtlType::OFF:
case VAssertCtlType::KILL: {
UINFO(9, "Generating assertctl for a module: " << m_modp);
nodep->replaceWith(new AstCExpr{fl,
"vlSymsp->_vm_contextp__->assertOnClear("s
+ std::to_string(nodep->ctlAssertTypes()) + " ,"s
+ std::to_string(nodep->ctlDirectiveTypes())
+ ");\n"s,
1});
break;
}
case VAssertCtlType::LOCK:
case VAssertCtlType::UNLOCK:
case VAssertCtlType::PASS_ON:
case VAssertCtlType::PASS_OFF:
case VAssertCtlType::FAIL_ON:
case VAssertCtlType::FAIL_OFF:
case VAssertCtlType::NONVACUOUS_ON:
case VAssertCtlType::VACUOUS_OFF: {
nodep->unlinkFrBack();
nodep->v3warn(E_UNSUPPORTED, "Unsupported: $assertcontrol control_type '" << cvtToStr(
static_cast<int>(nodep->ctlType())) << "'");
break;
}
default: {
nodep->unlinkFrBack();
nodep->v3warn(EC_ERROR, "Bad $assertcontrol control_type '"
<< cvtToStr(static_cast<int>(nodep->ctlType()))
<< "' (IEEE 1800-2023 Table 20-5)");
}
}
VL_DO_DANGLING(pushDeletep(nodep), nodep);
}
void visit(AstAssertIntrinsic* nodep) override { //
visitAssertionIterate(nodep, nodep->failsp());
}
void visit(AstCover* nodep) override { //
visitAssertionIterate(nodep, nullptr);
}
void visit(AstRestrict* nodep) override {
VL_RESTORER(m_inRestrict);
m_inRestrict = true;
iterateChildren(nodep);
// IEEE says simulator ignores these
VL_DO_DANGLING(pushDeletep(nodep->unlinkFrBack()), nodep);
}
void visit(AstNodeModule* nodep) override {
VL_RESTORER(m_modp);
VL_RESTORER(m_modPastNum);
VL_RESTORER(m_modStrobeNum);
m_modp = nodep;
m_modPastNum = 0;
m_modStrobeNum = 0;
iterateChildren(nodep);
}
void visit(AstNodeProcedure* nodep) override {
VL_RESTORER(m_procedurep);
m_procedurep = nodep;
iterateChildren(nodep);
}
void visit(AstGenBlock* nodep) override {
// This code is needed rather than a visitor in V3Begin,
// because V3Assert is called before V3Begin
VL_RESTORER(m_beginp);
m_beginp = nodep;
iterateChildren(nodep);
}
void visit(AstBegin* nodep) override {
// This code is needed rather than a visitor in V3Begin,
// because V3Assert is called before V3Begin
VL_RESTORER(m_beginp);
m_beginp = nodep;
iterateChildren(nodep);
}
void visit(AstNode* nodep) override { iterateChildren(nodep); }
public:
// CONSTRUCTORS
explicit AssertVisitor(AstNetlist* nodep) { iterate(nodep); }
~AssertVisitor() override {
V3Stats::addStat("Assertions, assert non-immediate statements", m_statAsNotImm);
V3Stats::addStat("Assertions, assert immediate statements", m_statAsImm);
V3Stats::addStat("Assertions, cover statements", m_statCover);
V3Stats::addStat("Assertions, full/parallel case", m_statAsFull);
V3Stats::addStat("Assertions, $past variables", m_statPastVars);
}
};
//######################################################################
// Top Assert class
void V3Assert::assertAll(AstNetlist* nodep) {
UINFO(2, __FUNCTION__ << ":");
{ AssertVisitor{nodep}; } // Destruct before checking
V3Global::dumpCheckGlobalTree("assert", 0, dumpTreeEitherLevel() >= 3);
}