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Merge pull request #2005 from YosysHQ/claire/fix1990

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Add "nowrshmsk" attribute, fix shift-and-mask bit slice write for signed offset
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Claire Wolf 2020-05-07 18:11:48 +02:00 • committed by GitHub
commit 0610424940
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9 changed files with 142 additions and 19 deletions
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3
README.md
View file

@ -281,6 +281,9 @@ Verilog Attributes and non-standard features
temporary variable within an always block. This is mostly used internally
by Yosys to synthesize Verilog functions and access arrays.
- The ``nowrshmsk`` attribute on a register prohibits the generation of
shift-and-mask type circuits for writing to bit slices of that register.
- The ``onehot`` attribute on wires mark them as one-hot state register. This
is used for example for memory port sharing and set by the fsm_map pass.

6
frontends/ast/ast.cc
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)
@ -110,6 +111,8 @@ std::string AST::type2str(AstNodeType type)
X(AST_SHIFT_RIGHT)
X(AST_SHIFT_SLEFT)
X(AST_SHIFT_SRIGHT)
X(AST_SHIFTX)
X(AST_SHIFT)
X(AST_LT)
X(AST_LE)
X(AST_EQ)
@ -615,6 +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, ")");
@ -628,6 +632,8 @@ void AstNode::dumpVlog(FILE *f, std::string indent) const
if (0) { case AST_SHIFT_RIGHT: txt = ">>"; }
if (0) { case AST_SHIFT_SLEFT: txt = "<<<"; }
if (0) { case AST_SHIFT_SRIGHT: txt = ">>>"; }
if (0) { case AST_SHIFTX: txt = "@shiftx@"; }
if (0) { case AST_SHIFT: txt = "@shift@"; }
if (0) { case AST_LT: txt = "<"; }
if (0) { case AST_LE: txt = "<="; }
if (0) { case AST_EQ: txt = "=="; }

3
frontends/ast/ast.h
View file

@ -75,6 +75,7 @@ namespace AST
AST_TO_BITS,
AST_TO_SIGNED,
AST_TO_UNSIGNED,
AST_SELFSZ,
AST_CONCAT,
AST_REPLICATE,
AST_BIT_NOT,
@ -91,6 +92,8 @@ namespace AST
AST_SHIFT_RIGHT,
AST_SHIFT_SLEFT,
AST_SHIFT_SRIGHT,
AST_SHIFTX,
AST_SHIFT,
AST_LT,
AST_LE,
AST_EQ,

23
frontends/ast/genrtlil.cc
View file

@ -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;
@ -856,6 +861,8 @@ void AstNode::detectSignWidthWorker(int &width_hint, bool &sign_hint, bool *foun
case AST_SHIFT_RIGHT:
case AST_SHIFT_SLEFT:
case AST_SHIFT_SRIGHT:
case AST_SHIFTX:
case AST_SHIFT:
case AST_POW:
children[0]->detectSignWidthWorker(width_hint, sign_hint, found_real);
break;
@ -1205,13 +1212,18 @@ RTLIL::SigSpec AstNode::genRTLIL(int width_hint, bool sign_hint)
AstNode *fake_ast = new AstNode(AST_NONE, clone(), children[0]->children.size() >= 2 ?
children[0]->children[1]->clone() : children[0]->children[0]->clone());
fake_ast->children[0]->delete_children();
RTLIL::SigSpec shift_val = fake_ast->children[1]->genRTLIL();
int fake_ast_width = 0;
bool fake_ast_sign = true;
fake_ast->children[1]->detectSignWidth(fake_ast_width, fake_ast_sign);
RTLIL::SigSpec shift_val = fake_ast->children[1]->genRTLIL(fake_ast_width, fake_ast_sign);
if (id2ast->range_right != 0) {
shift_val = current_module->Sub(NEW_ID, shift_val, id2ast->range_right, fake_ast->children[1]->is_signed);
shift_val = current_module->Sub(NEW_ID, shift_val, id2ast->range_right, fake_ast_sign);
fake_ast->children[1]->is_signed = true;
}
if (id2ast->range_swapped) {
shift_val = current_module->Sub(NEW_ID, RTLIL::SigSpec(source_width - width), shift_val, fake_ast->children[1]->is_signed);
shift_val = current_module->Sub(NEW_ID, RTLIL::SigSpec(source_width - width), shift_val, fake_ast_sign);
fake_ast->children[1]->is_signed = true;
}
if (GetSize(shift_val) >= 32)
@ -1265,7 +1277,8 @@ 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);
@ -1356,6 +1369,8 @@ RTLIL::SigSpec AstNode::genRTLIL(int width_hint, bool sign_hint)
if (0) { case AST_SHIFT_RIGHT: type_name = ID($shr); }
if (0) { case AST_SHIFT_SLEFT: type_name = ID($sshl); }
if (0) { case AST_SHIFT_SRIGHT: type_name = ID($sshr); }
if (0) { case AST_SHIFTX: type_name = ID($shiftx); }
if (0) { case AST_SHIFT: type_name = ID($shift); }
{
if (width_hint < 0)
detectSignWidth(width_hint, sign_hint);

62
frontends/ast/simplify.cc
View file

@ -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:
@ -1788,7 +1789,18 @@ bool AstNode::simplify(bool const_fold, bool at_zero, bool in_lvalue, int stage,
result_width = abs(int(left_at_zero_ast->integer - right_at_zero_ast->integer)) + 1;
}
if (0)
bool use_case_method = false;
if (children[0]->id2ast->attributes.count(ID::nowrshmsk)) {
AstNode *node = children[0]->id2ast->attributes.at(ID::nowrshmsk);
while (node->simplify(true, false, false, stage, -1, false, false)) { }
if (node->type != AST_CONSTANT)
log_file_error(filename, location.first_line, "Non-constant value for `nowrshmsk' attribute on `%s'!\n", children[0]->id2ast->str.c_str());
if (node->asAttrConst().as_bool())
use_case_method = true;
}
if (use_case_method)
{
// big case block
@ -1796,10 +1808,10 @@ bool AstNode::simplify(bool const_fold, bool at_zero, bool in_lvalue, int stage,
newNode = new AstNode(AST_CASE, shift_expr);
for (int i = 0; i < source_width; i++) {
int start_bit = children[0]->id2ast->range_right + i;
int end_bit = std::min(start_bit+result_width,source_width) - 1;
AstNode *cond = new AstNode(AST_COND, mkconst_int(start_bit, true));
AstNode *lvalue = children[0]->clone();
lvalue->delete_children();
int end_bit = std::min(start_bit+result_width,source_width) - 1;
lvalue->children.push_back(new AstNode(AST_RANGE,
mkconst_int(end_bit, true), mkconst_int(start_bit, true)));
cond->children.push_back(new AstNode(AST_BLOCK, new AstNode(type, lvalue, children[1]->clone())));
@ -1846,11 +1858,40 @@ bool AstNode::simplify(bool const_fold, bool at_zero, bool in_lvalue, int stage,
AstNode *shamt = shift_expr;
newNode->children.push_back(new AstNode(AST_ASSIGN_EQ, ref_mask->clone(),
new AstNode(AST_SHIFT_LEFT, mkconst_bits(std::vector<RTLIL::State>(result_width, State::S1), false), shamt->clone())));
newNode->children.push_back(new AstNode(AST_ASSIGN_EQ, ref_data->clone(),
new AstNode(AST_SHIFT_LEFT, new AstNode(AST_BIT_AND, mkconst_bits(std::vector<RTLIL::State>(result_width, State::S1), false), children[1]->clone()), shamt)));
newNode->children.push_back(new AstNode(type, lvalue, new AstNode(AST_BIT_OR, new AstNode(AST_BIT_AND, old_data, new AstNode(AST_BIT_NOT, ref_mask)), ref_data)));
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_sign_hint;
if (start_bit != 0) {
shamt = new AstNode(AST_SUB, shamt, mkconst_int(start_bit, true));
use_shift = true;
}
AstNode *t;
t = mkconst_bits(std::vector<RTLIL::State>(result_width, State::S1), false);
if (use_shift)
t = new AstNode(AST_SHIFT, t, new AstNode(AST_NEG, shamt->clone()));
else
t = new AstNode(AST_SHIFT_LEFT, t, shamt->clone());
t = new AstNode(AST_ASSIGN_EQ, ref_mask->clone(), t);
newNode->children.push_back(t);
t = new AstNode(AST_BIT_AND, mkconst_bits(std::vector<RTLIL::State>(result_width, State::S1), false), children[1]->clone());
if (use_shift)
t = new AstNode(AST_SHIFT, t, new AstNode(AST_NEG, shamt));
else
t = new AstNode(AST_SHIFT_LEFT, t, shamt);
t = new AstNode(AST_ASSIGN_EQ, ref_data->clone(), t);
newNode->children.push_back(t);
t = new AstNode(AST_BIT_AND, old_data, new AstNode(AST_BIT_NOT, ref_mask));
t = new AstNode(AST_BIT_OR, t, ref_data);
t = new AstNode(type, lvalue, t);
newNode->children.push_back(t);
}
goto apply_newNode;
@ -3026,6 +3067,7 @@ 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) {
@ -3034,10 +3076,10 @@ 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:

4
frontends/verilog/verilog_parser.y
View file

@ -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));
} |

1
kernel/constids.inc
View file

@ -125,6 +125,7 @@ X(nomem2init)
X(nomem2reg)
X(nomeminit)
X(nosync)
X(nowrshmsk)
X(O)
X(OFFSET)
X(onehot)

13
passes/tests/test_autotb.cc
View file

@ -81,6 +81,7 @@ static void autotest(std::ostream &f, RTLIL::Design *design, int num_iter, int s
f << stringf("integer i;\n");
f << stringf("integer file;\n\n");
f << stringf("reg [1023:0] filename;\n\n");
f << stringf("reg [31:0] xorshift128_x = 123456789;\n");
f << stringf("reg [31:0] xorshift128_y = 362436069;\n");
@ -305,9 +306,15 @@ static void autotest(std::ostream &f, RTLIL::Design *design, int num_iter, int s
}
f << stringf("initial begin\n");
f << stringf("\t// $dumpfile(\"testbench.vcd\");\n");
f << stringf("\t// $dumpvars(0, testbench);\n");
f << stringf("\tfile = $fopen(`outfile);\n");
f << stringf("\tif ($value$plusargs(\"VCD=%%s\", filename)) begin\n");
f << stringf("\t\t$dumpfile(filename);\n");
f << stringf("\t\t$dumpvars(0, testbench);\n");
f << stringf("\tend\n");
f << stringf("\tif ($value$plusargs(\"OUT=%%s\", filename)) begin\n");
f << stringf("\t\tfile = $fopen(filename);\n");
f << stringf("\tend else begin\n");
f << stringf("\t\tfile = $fopen(`outfile);\n");
f << stringf("\tend\n");
for (auto module : design->modules())
if (!module->get_bool_attribute(ID::gentb_skip))
f << stringf("\t%s;\n", idy(module->name.str(), "test").c_str());

46
tests/simple/partsel.v
View file

@ -64,3 +64,49 @@ endmodule
module partsel_test003(input [2:0] a, b, input [31:0] din, output [3:0] dout);
assign dout = din[a*b +: 2];
endmodule
module partsel_test004 (
input [31:0] din,
input signed [4:0] n,
output reg [31:0] dout
);
always @(*) begin
dout = 0;
dout[n+1 +: 2] = din[n +: 2];
end
endmodule
module partsel_test005 (
input [31:0] din,
input signed [4:0] n,
output reg [31:0] dout
);
always @(*) begin
dout = 0;
dout[n+1] = din[n];
end
endmodule
module partsel_test006 (
input [31:-32] din,
input signed [4:0] n,
output reg [31:-32] dout
);
always @(*) begin
dout = 0;
dout[n+1 +: 2] = din[n +: 2];
end
endmodule
module partsel_test007 (
input [31:-32] din,
input signed [4:0] n,
output reg [31:-32] dout
);
always @(*) begin
dout = 0;
dout[n+1] = din[n];
end
endmodule