moves instruction decoder into own class
This commit is contained in:
parent
60808c8649
commit
6ee484a771
|
@ -20,6 +20,7 @@ set(LIB_SOURCES
|
||||||
src/iss/arch/tgc5c.cpp
|
src/iss/arch/tgc5c.cpp
|
||||||
src/vm/interp/vm_tgc5c.cpp
|
src/vm/interp/vm_tgc5c.cpp
|
||||||
src/vm/fp_functions.cpp
|
src/vm/fp_functions.cpp
|
||||||
|
src/vm/instruction_decoder.cpp
|
||||||
src/iss/semihosting/semihosting.cpp
|
src/iss/semihosting/semihosting.cpp
|
||||||
)
|
)
|
||||||
|
|
||||||
|
|
|
@ -0,0 +1,103 @@
|
||||||
|
/*******************************************************************************
|
||||||
|
* Copyright (C) 2024 MINRES Technologies GmbH
|
||||||
|
* All rights reserved.
|
||||||
|
*
|
||||||
|
* Redistribution and use in source and binary forms, with or without
|
||||||
|
* modification, are permitted provided that the following conditions are met:
|
||||||
|
*
|
||||||
|
* 1. Redistributions of source code must retain the above copyright notice,
|
||||||
|
* this list of conditions and the following disclaimer.
|
||||||
|
*
|
||||||
|
* 2. Redistributions in binary form must reproduce the above copyright notice,
|
||||||
|
* this list of conditions and the following disclaimer in the documentation
|
||||||
|
* and/or other materials provided with the distribution.
|
||||||
|
*
|
||||||
|
* 3. Neither the name of the copyright holder nor the names of its contributors
|
||||||
|
* may be used to endorse or promote products derived from this software
|
||||||
|
* without specific prior written permission.
|
||||||
|
*
|
||||||
|
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
|
||||||
|
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
||||||
|
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
||||||
|
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
|
||||||
|
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
|
||||||
|
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
|
||||||
|
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
|
||||||
|
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
|
||||||
|
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
|
||||||
|
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
|
||||||
|
* POSSIBILITY OF SUCH DAMAGE.
|
||||||
|
*
|
||||||
|
* Contributors:
|
||||||
|
* alex@minres.com - initial implementation
|
||||||
|
******************************************************************************/
|
||||||
|
|
||||||
|
#include <algorithm>
|
||||||
|
#include <cassert>
|
||||||
|
#include <cstddef>
|
||||||
|
#include <cstdint>
|
||||||
|
#include <limits>
|
||||||
|
#include <numeric>
|
||||||
|
#include <vector>
|
||||||
|
#include <vm/instruction_decoder.h>
|
||||||
|
|
||||||
|
decoder::decoder(std::vector<generic_instruction_descriptor> instr_list) {
|
||||||
|
for(auto instr : instr_list) {
|
||||||
|
root.instrs.push_back(instr);
|
||||||
|
}
|
||||||
|
populate_decoding_tree(root);
|
||||||
|
}
|
||||||
|
|
||||||
|
void decoder::populate_decoding_tree(decoding_tree_node& parent) {
|
||||||
|
// create submask
|
||||||
|
parent.submask =
|
||||||
|
std::accumulate(parent.instrs.begin(), parent.instrs.end(), std::numeric_limits<uint32_t>::max(),
|
||||||
|
[](int current_submask, const generic_instruction_descriptor& instr) { return current_submask & instr.mask; });
|
||||||
|
// put each instr according to submask&encoding into children
|
||||||
|
for(auto instr : parent.instrs) {
|
||||||
|
bool foundMatch = false;
|
||||||
|
for(auto& child : parent.children) {
|
||||||
|
// use value as identifying trait
|
||||||
|
if(child.value == (instr.value & parent.submask)) {
|
||||||
|
child.instrs.push_back(instr);
|
||||||
|
foundMatch = true;
|
||||||
|
}
|
||||||
|
}
|
||||||
|
if(!foundMatch) {
|
||||||
|
decoding_tree_node child = decoding_tree_node(instr.value & parent.submask);
|
||||||
|
child.instrs.push_back(instr);
|
||||||
|
parent.children.push_back(child);
|
||||||
|
}
|
||||||
|
}
|
||||||
|
parent.instrs.clear();
|
||||||
|
// call populate_decoding_tree for all children
|
||||||
|
if(parent.children.size() > 1)
|
||||||
|
for(auto& child : parent.children) {
|
||||||
|
populate_decoding_tree(child);
|
||||||
|
}
|
||||||
|
else {
|
||||||
|
// sort instrs by value of the mask, so we have the least restrictive mask last
|
||||||
|
std::sort(parent.children[0].instrs.begin(), parent.children[0].instrs.end(),
|
||||||
|
[](const generic_instruction_descriptor& instr1, const generic_instruction_descriptor& instr2) {
|
||||||
|
return instr1.mask > instr2.mask;
|
||||||
|
});
|
||||||
|
}
|
||||||
|
}
|
||||||
|
uint32_t decoder::decode_instr(uint32_t word) { return _decode_instr(this->root, word); }
|
||||||
|
uint32_t decoder::_decode_instr(decoding_tree_node const& node, uint32_t word) {
|
||||||
|
if(!node.children.size()) {
|
||||||
|
if(node.instrs.size() == 1)
|
||||||
|
return node.instrs[0].index;
|
||||||
|
for(auto instr : node.instrs) {
|
||||||
|
if((instr.mask & word) == instr.value)
|
||||||
|
return instr.index;
|
||||||
|
}
|
||||||
|
} else {
|
||||||
|
for(auto child : node.children) {
|
||||||
|
if(child.value == (node.submask & word)) {
|
||||||
|
return _decode_instr(child, word);
|
||||||
|
}
|
||||||
|
}
|
||||||
|
}
|
||||||
|
return std::numeric_limits<uint32_t>::max();
|
||||||
|
}
|
|
@ -0,0 +1,63 @@
|
||||||
|
/*******************************************************************************
|
||||||
|
* Copyright (C) 2024 MINRES Technologies GmbH
|
||||||
|
* All rights reserved.
|
||||||
|
*
|
||||||
|
* Redistribution and use in source and binary forms, with or without
|
||||||
|
* modification, are permitted provided that the following conditions are met:
|
||||||
|
*
|
||||||
|
* 1. Redistributions of source code must retain the above copyright notice,
|
||||||
|
* this list of conditions and the following disclaimer.
|
||||||
|
*
|
||||||
|
* 2. Redistributions in binary form must reproduce the above copyright notice,
|
||||||
|
* this list of conditions and the following disclaimer in the documentation
|
||||||
|
* and/or other materials provided with the distribution.
|
||||||
|
*
|
||||||
|
* 3. Neither the name of the copyright holder nor the names of its contributors
|
||||||
|
* may be used to endorse or promote products derived from this software
|
||||||
|
* without specific prior written permission.
|
||||||
|
*
|
||||||
|
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
|
||||||
|
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
||||||
|
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
||||||
|
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
|
||||||
|
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
|
||||||
|
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
|
||||||
|
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
|
||||||
|
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
|
||||||
|
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
|
||||||
|
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
|
||||||
|
* POSSIBILITY OF SUCH DAMAGE.
|
||||||
|
*
|
||||||
|
* Contributors:
|
||||||
|
* alex@minres.com - initial implementation
|
||||||
|
******************************************************************************/
|
||||||
|
|
||||||
|
#include <cstddef>
|
||||||
|
#include <cstdint>
|
||||||
|
#include <limits>
|
||||||
|
#include <vector>
|
||||||
|
|
||||||
|
struct generic_instruction_descriptor {
|
||||||
|
uint32_t value;
|
||||||
|
uint32_t mask;
|
||||||
|
uint32_t index;
|
||||||
|
};
|
||||||
|
|
||||||
|
struct decoding_tree_node {
|
||||||
|
std::vector<generic_instruction_descriptor> instrs;
|
||||||
|
std::vector<decoding_tree_node> children;
|
||||||
|
uint32_t submask = std::numeric_limits<uint32_t>::max();
|
||||||
|
uint32_t value;
|
||||||
|
decoding_tree_node(uint32_t value)
|
||||||
|
: value(value) {}
|
||||||
|
};
|
||||||
|
class decoder {
|
||||||
|
public:
|
||||||
|
decoder(std::vector<generic_instruction_descriptor> instr_list);
|
||||||
|
uint32_t decode_instr(uint32_t word);
|
||||||
|
|
||||||
|
private:
|
||||||
|
decoding_tree_node root{decoding_tree_node(std::numeric_limits<uint32_t>::max())};
|
||||||
|
void populate_decoding_tree(decoding_tree_node& root);
|
||||||
|
uint32_t _decode_instr(decoding_tree_node const& node, uint32_t word);
|
||||||
|
};
|
Loading…
Reference in New Issue