More aggressively prune unreachable code as follows.
When no control flow edges reach a merge block or continue target:
- delete their contents so that:
- a merge block becomes OpLabel, then OpUnreachable
- a continue target becomes OpLabel, then an OpBranch back to the
loop header
- any basic block which is dominated by such a merge block or continue
target is removed as well.
- decorations targeting the removed instructions are removed.
Enables the SPIR-V builder post-processing step the GLSLANG_WEB case.
20 lines
405 B
GLSL
20 lines
405 B
GLSL
#version 450
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layout(location =0 ) in int c;
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layout(location =0 ) out int o;
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void main() {
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int i = 0;
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o = 1;
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// This has non-trivial continue target.
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for (i=0; i < 5; ++i, o=99) {
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o = 2;
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return;
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o = 3;
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}
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// This is considered reachable since Glslang codegen will
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// create a conditional branch in the header, and one arm
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// of that branch reaches this merge block.
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o = 4;
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}
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