Add AST_SELFSZ and improve handling of bit slices

Signed-off-by: Claire Wolf <claire@symbioticeda.com>
This commit is contained in:
Claire Wolf 2020-04-29 14:28:04 +02:00
parent bbbce0d1c5
commit 589ed2d970
5 changed files with 22 additions and 7 deletions

View File

@ -94,6 +94,7 @@ std::string AST::type2str(AstNodeType type)
X(AST_TO_BITS)
X(AST_TO_SIGNED)
X(AST_TO_UNSIGNED)
X(AST_SELFSZ)
X(AST_CONCAT)
X(AST_REPLICATE)
X(AST_BIT_NOT)
@ -617,6 +618,7 @@ void AstNode::dumpVlog(FILE *f, std::string indent) const
if (0) { case AST_POS: txt = "+"; }
if (0) { case AST_NEG: txt = "-"; }
if (0) { case AST_LOGIC_NOT: txt = "!"; }
if (0) { case AST_SELFSZ: txt = "@selfsz@"; }
fprintf(f, "%s(", txt.c_str());
children[0]->dumpVlog(f, "");
fprintf(f, ")");

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@ -75,6 +75,7 @@ namespace AST
AST_TO_BITS,
AST_TO_SIGNED,
AST_TO_UNSIGNED,
AST_SELFSZ,
AST_CONCAT,
AST_REPLICATE,
AST_BIT_NOT,

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@ -809,6 +809,11 @@ void AstNode::detectSignWidthWorker(int &width_hint, bool &sign_hint, bool *foun
sign_hint = false;
break;
case AST_SELFSZ:
sub_width_hint = 0;
children.at(0)->detectSignWidthWorker(sub_width_hint, sign_hint);
break;
case AST_CONCAT:
for (auto child : children) {
sub_width_hint = 0;
@ -1267,7 +1272,8 @@ RTLIL::SigSpec AstNode::genRTLIL(int width_hint, bool sign_hint)
// just pass thru the signal. the parent will evaluate the is_signed property and interpret the SigSpec accordingly
case AST_TO_SIGNED:
case AST_TO_UNSIGNED: {
case AST_TO_UNSIGNED:
case AST_SELFSZ: {
RTLIL::SigSpec sig = children[0]->genRTLIL();
if (sig.size() < width_hint)
sig.extend_u0(width_hint, sign_hint);

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@ -608,6 +608,7 @@ bool AstNode::simplify(bool const_fold, bool at_zero, bool in_lvalue, int stage,
case AST_TO_BITS:
case AST_TO_SIGNED:
case AST_TO_UNSIGNED:
case AST_SELFSZ:
case AST_CONCAT:
case AST_REPLICATE:
case AST_REDUCE_AND:
@ -1855,8 +1856,12 @@ bool AstNode::simplify(bool const_fold, bool at_zero, bool in_lvalue, int stage,
AstNode *shamt = shift_expr;
int shamt_width_hint = 0;
bool shamt_sign_hint = true;
shamt->detectSignWidth(shamt_width_hint, shamt_sign_hint);
int start_bit = children[0]->id2ast->range_right;
bool use_shift = shamt->is_signed;
bool use_shift = shamt_sign_hint;
if (start_bit != 0) {
shamt = new AstNode(AST_SUB, shamt, mkconst_int(start_bit, true));
@ -3060,6 +3065,7 @@ replace_fcall_later:;
}
}
break;
if (0) { case AST_SELFSZ: const_func = RTLIL::const_pos; }
if (0) { case AST_POS: const_func = RTLIL::const_pos; }
if (0) { case AST_NEG: const_func = RTLIL::const_neg; }
if (children[0]->type == AST_CONSTANT) {
@ -3068,10 +3074,10 @@ replace_fcall_later:;
} else
if (children[0]->isConst()) {
newNode = new AstNode(AST_REALVALUE);
if (type == AST_POS)
newNode->realvalue = +children[0]->asReal(sign_hint);
else
if (type == AST_NEG)
newNode->realvalue = -children[0]->asReal(sign_hint);
else
newNode->realvalue = +children[0]->asReal(sign_hint);
}
break;
case AST_TERNARY:

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@ -645,13 +645,13 @@ non_opt_range:
} |
'[' expr TOK_POS_INDEXED expr ']' {
$$ = new AstNode(AST_RANGE);
AstNode *expr = new AstNode(AST_CONCAT, $2);
AstNode *expr = new AstNode(AST_SELFSZ, $2);
$$->children.push_back(new AstNode(AST_SUB, new AstNode(AST_ADD, expr->clone(), $4), AstNode::mkconst_int(1, true)));
$$->children.push_back(new AstNode(AST_ADD, expr, AstNode::mkconst_int(0, true)));
} |
'[' expr TOK_NEG_INDEXED expr ']' {
$$ = new AstNode(AST_RANGE);
AstNode *expr = new AstNode(AST_CONCAT, $2);
AstNode *expr = new AstNode(AST_SELFSZ, $2);
$$->children.push_back(new AstNode(AST_ADD, expr, AstNode::mkconst_int(0, true)));
$$->children.push_back(new AstNode(AST_SUB, new AstNode(AST_ADD, expr->clone(), AstNode::mkconst_int(1, true)), $4));
} |