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GP-2559 Calculate maximum precision reaching floating-point operations

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caheckman 2024-06-17 21:49:17 +00:00
parent be305db930
commit 520dc99b11
15 changed files with 602 additions and 57 deletions
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21
Ghidra/Features/Decompiler/src/decompile/cpp/subflow.hh
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@ -4,9 +4,9 @@
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
*
* http://www.apache.org/licenses/LICENSE-2.0
*
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
@ -211,10 +211,24 @@ public:
/// and then rewrites the data-flow in terms of the lower precision, eliminating the
/// precision conversions.
class SubfloatFlow : public TransformManager {
/// \brief Internal state for walking floating-point data-flow and computing precision
class State {
public:
PcodeOp *op; ///< Operation being traversed
int4 slot; ///< Input edge being traversed
int4 maxPrecision; ///< Maximum precision traversed through inputs so far
State(PcodeOp *o) {
op = o; slot = 0; maxPrecision = 0; } ///< Constructor
/// \brief Accumulate precision coming in from an input Varnode to \b this node
void incorporateInputSize(int4 sz) { maxPrecision = (maxPrecision < sz) ? sz : maxPrecision; }
};
int4 precision; ///< Number of bytes of precision in the logical flow
int4 terminatorCount; ///< Number of terminating nodes reachable via the root
const FloatFormat *format; ///< The floating-point format of the logical value
vector<TransformVar *> worklist; ///< Current list of placeholders that still need to be traced
map<PcodeOp *,int4> maxPrecisionMap; ///< Maximum precision flowing into a particular floating-point op
int4 maxPrecision(Varnode *vn); ///< Calculate maximum floating-point precision reaching a given Varnode
bool exceedsPrecision(PcodeOp *op); ///< Determine if the given op exceeds our \b precision
TransformVar *setReplacement(Varnode *vn);
bool traceForward(TransformVar *rvn);
bool traceBackward(TransformVar *rvn);
@ -249,9 +263,12 @@ class LaneDivide : public TransformManager {
void buildBinaryOp(OpCode opc,PcodeOp *op,TransformVar *in0Vars,TransformVar *in1Vars,TransformVar *outVars,int4 numLanes);
bool buildPiece(PcodeOp *op,TransformVar *outVars,int4 numLanes,int4 skipLanes);
bool buildMultiequal(PcodeOp *op,TransformVar *outVars,int4 numLanes,int4 skipLanes);
bool buildIndirect(PcodeOp *op,TransformVar *outVars,int4 numLanes,int4 skipLanes);
bool buildStore(PcodeOp *op,int4 numLanes,int4 skipLanes);
bool buildLoad(PcodeOp *op,TransformVar *outVars,int4 numLanes,int4 skipLanes);
bool buildRightShift(PcodeOp *op,TransformVar *outVars,int4 numLanes,int4 skipLanes);
bool buildLeftShift(PcodeOp *op,TransformVar *outVars,int4 numLanes,int4 skipLanes);
bool buildZext(PcodeOp *op,TransformVar *outVars,int4 numLanes,int4 skipLanes);
bool traceForward(TransformVar *rvn,int4 numLanes,int4 skipLanes);
bool traceBackward(TransformVar *rvn,int4 numLanes,int4 skipLanes);
bool processNextWork(void); ///< Process the next Varnode on the work list