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Fixed mem assignment in left-hand-side concatenation

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This commit is contained in:
Clifford Wolf 2016-07-08 14:31:06 +02:00
parent b782076698
commit 9a101dc1f7
2 changed files with 57 additions and 0 deletions
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44
frontends/ast/simplify.cc
View file

@ -1418,6 +1418,50 @@ skip_dynamic_range_lvalue_expansion:;
goto apply_newNode;
}
// assignment with nontrivial member in left-hand concat expression -> split assignment
if ((type == AST_ASSIGN_EQ || type == AST_ASSIGN_LE) && children[0]->type == AST_CONCAT && width_hint > 0)
{
bool found_nontrivial_member = false;
for (auto child : children[0]->children) {
if (child->type == AST_IDENTIFIER && child->id2ast != NULL && child->id2ast->type == AST_MEMORY)
found_nontrivial_member = true;
}
if (found_nontrivial_member)
{
newNode = new AstNode(AST_BLOCK);
AstNode *wire_tmp = new AstNode(AST_WIRE, new AstNode(AST_RANGE, mkconst_int(width_hint-1, true), mkconst_int(0, true)));
wire_tmp->str = stringf("$splitcmplxassign$%s:%d$%d", filename.c_str(), linenum, autoidx++);
current_ast_mod->children.push_back(wire_tmp);
current_scope[wire_tmp->str] = wire_tmp;
wire_tmp->attributes["\\nosync"] = AstNode::mkconst_int(1, false);
while (wire_tmp->simplify(true, false, false, 1, -1, false, false)) { }
AstNode *wire_tmp_id = new AstNode(AST_IDENTIFIER);
wire_tmp_id->str = wire_tmp->str;
newNode->children.push_back(new AstNode(AST_ASSIGN_EQ, wire_tmp_id, children[1]->clone()));
int cursor = 0;
for (auto child : children[0]->children)
{
int child_width_hint = -1;
bool child_sign_hint = true;
child->detectSignWidth(child_width_hint, child_sign_hint);
AstNode *rhs = wire_tmp_id->clone();
rhs->children.push_back(new AstNode(AST_RANGE, AstNode::mkconst_int(cursor+child_width_hint-1, true), AstNode::mkconst_int(cursor, true)));
newNode->children.push_back(new AstNode(type, child->clone(), rhs));
cursor += child_width_hint;
}
goto apply_newNode;
}
}
// assignment with memory in left-hand side expression -> replace with memory write port
if (stage > 1 && (type == AST_ASSIGN_EQ || type == AST_ASSIGN_LE) && children[0]->type == AST_IDENTIFIER &&
children[0]->id2ast && children[0]->id2ast->type == AST_MEMORY && children[0]->id2ast->children.size() >= 2 &&

13
tests/simple/memory.v
View file

@ -264,3 +264,16 @@ module memtest11(clk, wen, waddr, raddr, wdata, rdata);
end
endmodule
// ----------------------------------------------------------
module memtest12 (
input clk,
input [1:0] adr,
input [1:0] din,
output reg [1:0] q
);
reg [1:0] ram [3:0];
always@(posedge clk)
{ram[adr], q} <= {din, ram[adr]};
endmodule