glslang -> SPV: 1) Include post switch-break unreachable blocks and 2) Generally, don't emit degenerate (basically empty) unreachable blocks.
git-svn-id: https://cvs.khronos.org/svn/repos/ogl/trunk/ecosystem/public/sdk/tools/glslang@31023 e7fa87d3-cd2b-0410-9028-fcbf551c1848
diff --git a/SPIRV/spvIR.h b/SPIRV/spvIR.h
index 585af82..6ea0a0c 100644
--- a/SPIRV/spvIR.h
+++ b/SPIRV/spvIR.h
@@ -162,8 +162,6 @@
class Block {
public:
- // Setting insert to true indicates to add this new block
- // to the end of the parent function.
Block(Id id, Function& parent);
virtual ~Block()
{
@@ -177,6 +175,8 @@
void addPredecessor(Block* pred) { predecessors.push_back(pred); }
void addLocalVariable(Instruction* inst) { localVariables.push_back(inst); }
int getNumPredecessors() const { return (int)predecessors.size(); }
+ void setUnreachable() { unreachable = true; }
+ bool isUnreachable() const { return unreachable; }
bool isTerminated() const
{
@@ -195,6 +195,12 @@
void dump(std::vector<unsigned int>& out) const
{
+ // skip the degenerate unreachable blocks
+ // TODO: code gen: skip all unreachable blocks (transitive closure)
+ // (but, until that's done safer to keep non-degenerate unreachable blocks, in case others depend on something)
+ if (unreachable && instructions.size() <= 2)
+ return;
+
instructions[0]->dump(out);
for (int i = 0; i < (int)localVariables.size(); ++i)
localVariables[i]->dump(out);
@@ -212,6 +218,11 @@
std::vector<Block*> predecessors;
std::vector<Instruction*> localVariables;
Function& parent;
+
+ // track whether this block is known to be uncreachable (not necessarily
+ // true for all unreachable blocks, but should be set at least
+ // for the extraneous ones introduced by the builder).
+ bool unreachable;
};
//
@@ -338,7 +349,7 @@
parent.mapInstruction(inst);
}
-__inline Block::Block(Id id, Function& parent) : parent(parent)
+__inline Block::Block(Id id, Function& parent) : parent(parent), unreachable(false)
{
instructions.push_back(new Instruction(id, NoType, OpLabel));
}