Spec Constant Operations

Approach:
Add a flag in `Builder` to indicate 'spec constant mode' and 'normal
mode'. When the builder is in 'normal mode', nothing changed. When the
builder is in 'spec constant mode', binary, unary and other instruction
creation rountines will be redirected to `createSpecConstantOp()` to
create instrution at module level with `OpSpecConstantOp <original
opcode> <operands>`.

'spec constant mode' should be enabled if and only if we are creating
spec constants. So a flager setter/recover guard is added when handling
binary/unary nodes in `createSpvConstantsFromConstSubTree()`.

Note when handling spec constants which are represented as ConstantUnion
Node, we should not use `OpSpecConstantOp` to initialize the composite
constant, so builder is set to 'normal mode'.

Tests:
Tests are added in Test/spv.specConstantOperations.vert, including:

1) Arithmetic, shift opeations for both scalar and composite type spec constants.
2) Size conversion from/to float and double for both scalar and vector.
3) Bitwise and/or/xor for both scalar and vector.
4) Unary negate/not for both scalar and vector.
5) Vector swizzles.
6) Comparisons for scalars.
7) == and != for composite type spec constants

Issues:
1) To implement == and != for composite type spec constants, the Spec needs
to allow OpAll, OpAny, OpFOrdEqual, OpFUnordEqual, OpOrdNotEqual,
OpFUnordNotEqual. Currently none of them are allowed in the Spec.
This commit is contained in:
qining
2016-03-21 09:51:37 -04:00
parent c3869fee41
commit 135452061a
6 changed files with 506 additions and 13 deletions

View File

@@ -262,6 +262,7 @@ public:
Id createTriOp(Op, Id typeId, Id operand1, Id operand2, Id operand3);
Id createOp(Op, Id typeId, const std::vector<Id>& operands);
Id createFunctionCall(spv::Function*, std::vector<spv::Id>&);
Id createSpecConstantOp(Op, Id typeId, const std::vector<spv::Id>& operands, const std::vector<unsigned>& literals);
// Take an rvalue (source) and a set of channels to extract from it to
// make a new rvalue, which is returned.
@@ -521,6 +522,13 @@ public:
void createConditionalBranch(Id condition, Block* thenBlock, Block* elseBlock);
void createLoopMerge(Block* mergeBlock, Block* continueBlock, unsigned int control);
// Sets to generate opcode for specialization constants.
void setToSpecConstCodeGenMode() { generatingOpCodeForSpecConst = true; }
// Sets to generate opcode for non-specialization constants (normal mode).
void setToNormalCodeGenMode() { generatingOpCodeForSpecConst = false; }
// Check if the builder is generating code for spec constants.
bool isInSpecConstCodeGenMode() { return generatingOpCodeForSpecConst; }
protected:
Id makeIntConstant(Id typeId, unsigned value, bool specConstant);
Id findScalarConstant(Op typeClass, Op opcode, Id typeId, unsigned value) const;
@@ -544,6 +552,7 @@ public:
Block* buildPoint;
Id uniqueId;
Function* mainFunction;
bool generatingOpCodeForSpecConst;
AccessChain accessChain;
// special blocks of instructions for output