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Fix late constant division by zero giving X error, bug775.

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This commit is contained in:
Wilson Snyder
2014-06-09 22:27:04 -04:00
parent 71b2eed32c
commit 475e4207cc
8 changed files with 67 additions and 6 deletions
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src/V3Number.cpp
+21 -5
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@@ -25,6 +25,7 @@
#include <cstdarg>
#include <algorithm>
#include <iomanip>
#include "V3Global.h"
#include "V3Number.h"
#define MAX_SPRINTF_DOUBLE_SIZE 100 // Maximum characters with a sprintf %e/%f/%g (probably < 30)
@@ -323,6 +324,7 @@ V3Number& V3Number::setAllBits1() {
return *this;
}
V3Number& V3Number::setAllBitsX() {
// Use setAllBitsXRemoved if calling this based on a non-X/Z input value such as divide by zero
for (int i=0; i<words(); i++) { m_value[i]=m_valueX[i] = ~0; }
opCleanThis();
return *this;
@@ -332,6 +334,20 @@ V3Number& V3Number::setAllBitsZ() {
opCleanThis();
return *this;
}
V3Number& V3Number::setAllBitsXRemoved() {
if (!v3Global.constRemoveXs()) {
return setAllBitsX();
} else {
// If we get a divide by zero we get Xs.
// But after V3Unknown we have removed Xs, so use --x-assign to direct-insert 0/1
if (v3Global.opt.xAssign() == "1") {
return setAllBits1();
} else {
return setAllBits0();
}
}
}
V3Number& V3Number::setMask(int nbits) {
setZero();
for (int bit=0; bit<nbits; bit++) { setBit(bit,1); }
@@ -1248,7 +1264,7 @@ V3Number& V3Number::opDiv (const V3Number& lhs, const V3Number& rhs) {
UINFO(9, "opdiv "<<lhs<<" "<<rhs<<endl);
// i op j, max(L(lhs),L(rhs)) bit return, if any 4-state, 4-state return
if (lhs.isFourState() || rhs.isFourState()) return setAllBitsX();
if (rhs.isEqZero()) return setAllBitsX();
if (rhs.isEqZero()) return setAllBitsXRemoved();
if (lhs.width()<=64) {
setQuad(lhs.toUQuad() / rhs.toUQuad());
return *this;
@@ -1261,7 +1277,7 @@ V3Number& V3Number::opDivS (const V3Number& lhs, const V3Number& rhs) {
// Signed divide
//UINFO(9, ">>divs-start "<<lhs<<" "<<rhs<<endl);
if (lhs.isFourState() || rhs.isFourState()) return setAllBitsX();
if (rhs.isEqZero()) return setAllBitsX();
if (rhs.isEqZero()) return setAllBitsXRemoved();
V3Number lhsNoSign = lhs; if (lhs.isNegative()) lhsNoSign.opNegate(lhs);
V3Number rhsNoSign = rhs; if (rhs.isNegative()) rhsNoSign.opNegate(rhs);
V3Number qNoSign = opDiv(lhsNoSign,rhsNoSign);
@@ -1278,7 +1294,7 @@ V3Number& V3Number::opDivS (const V3Number& lhs, const V3Number& rhs) {
V3Number& V3Number::opModDiv (const V3Number& lhs, const V3Number& rhs) {
// i op j, max(L(lhs),L(rhs)) bit return, if any 4-state, 4-state return
if (lhs.isFourState() || rhs.isFourState()) return setAllBitsX();
if (rhs.isEqZero()) return setAllBitsX();
if (rhs.isEqZero()) return setAllBitsXRemoved();
if (lhs.width()<=64) {
setQuad(lhs.toUQuad() % rhs.toUQuad());
return *this;
@@ -1290,7 +1306,7 @@ V3Number& V3Number::opModDiv (const V3Number& lhs, const V3Number& rhs) {
V3Number& V3Number::opModDivS (const V3Number& lhs, const V3Number& rhs) {
// Signed moddiv
if (lhs.isFourState() || rhs.isFourState()) return setAllBitsX();
if (rhs.isEqZero()) return setAllBitsX();
if (rhs.isEqZero()) return setAllBitsXRemoved();
V3Number lhsNoSign = lhs; if (lhs.isNegative()) lhsNoSign.opNegate(lhs);
V3Number rhsNoSign = rhs; if (rhs.isNegative()) rhsNoSign.opNegate(rhs);
V3Number qNoSign = opModDiv(lhsNoSign,rhsNoSign);
@@ -1428,7 +1444,7 @@ V3Number& V3Number::opPow (const V3Number& lhs, const V3Number& rhs, bool lsign,
if (lhs.width()>64) m_fileline->v3fatalSrc("Unsupported: Large >64bit ** power operator not implemented yet: "<<*this);
if (rhs.width()>64) m_fileline->v3fatalSrc("Unsupported: Large >64bit ** power operator not implemented yet: "<<*this);
if (rsign && rhs.isNegative()) {
if (lhs.isEqZero()) return setAllBitsX();
if (lhs.isEqZero()) return setAllBitsXRemoved();
else if (lhs.isEqOne()) return setQuad(1);
else if (lsign && lhs.isEqAllOnes()) {
if (rhs.bitIs1(0)) return setAllBits1(); // -1^odd=-1