Merge pull request #843 from YosysHQ/clifford/mem2regconstidx

Use mem2reg on memories that only have constant-index write ports
This commit is contained in:
Clifford Wolf 2019-03-02 08:40:54 -08:00 committed by GitHub
commit f2f5ecd834
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
2 changed files with 13 additions and 0 deletions

View File

@ -214,6 +214,8 @@ namespace AST
MEM2REG_FL_SET_ASYNC = 0x00000800,
MEM2REG_FL_EQ2 = 0x00001000,
MEM2REG_FL_CMPLX_LHS = 0x00002000,
MEM2REG_FL_CONST_LHS = 0x00004000,
MEM2REG_FL_VAR_LHS = 0x00008000,
/* proc flags */
MEM2REG_FL_EQ1 = 0x01000000,

View File

@ -113,6 +113,9 @@ bool AstNode::simplify(bool const_fold, bool at_zero, bool in_lvalue, int stage,
if (memflags & AstNode::MEM2REG_FL_CMPLX_LHS)
goto verbose_activate;
if ((memflags & AstNode::MEM2REG_FL_CONST_LHS) && !(memflags & AstNode::MEM2REG_FL_VAR_LHS))
goto verbose_activate;
// log("Note: Not replacing memory %s with list of registers (flags=0x%08lx).\n", mem->str.c_str(), long(memflags));
continue;
@ -2936,6 +2939,14 @@ void AstNode::mem2reg_as_needed_pass1(dict<AstNode*, pool<std::string>> &mem2reg
proc_flags[mem] |= AstNode::MEM2REG_FL_EQ1;
}
// remember if this is a constant index or not
if (children[0]->children.size() && children[0]->children[0]->type == AST_RANGE && children[0]->children[0]->children.size()) {
if (children[0]->children[0]->children[0]->type == AST_CONSTANT)
mem2reg_candidates[mem] |= AstNode::MEM2REG_FL_CONST_LHS;
else
mem2reg_candidates[mem] |= AstNode::MEM2REG_FL_VAR_LHS;
}
// remember where this is
if (flags & MEM2REG_FL_INIT) {
if (!(mem2reg_candidates[mem] & AstNode::MEM2REG_FL_SET_INIT))