mirror of
https://github.com/KhronosGroup/glslang
synced 2024-11-08 19:40:06 +00:00
8c3d5b4b6c
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.
47 lines
1.5 KiB
JavaScript
47 lines
1.5 KiB
JavaScript
#version 450
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#extension GL_EXT_control_flow_attributes : enable
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bool cond;
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void f0() {
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[[loop]] for (;;) { }
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}
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void f1() {
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[[dont_unroll]] while(true) { }
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}
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void main()
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{
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[[unroll]] for (int i = 0; i < 8; ++i) { }
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f0();
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[[dependency_infinite]] do { } while(true);
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[[dependency_length(1+3)]] for (int i = 0; i < 8; ++i) { }
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[[flatten]] if (cond) { } else { }
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[[branch]] if (cond) cond = false;
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[[dont_flatten]] switch(3) { } // dropped
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[[dont_flatten]] switch(3) { case 3: break; }
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// warnings on all these
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[[unroll(2)]] for (int i = 0; i < 8; ++i) { }
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[[dont_unroll(-2)]] while(true) { }
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[[dependency_infinite(3)]] do { } while(true);
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[[dependency_length]] for (int i = 0; i < 8; ++i) { }
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[[flatten(3)]] if (cond) { } else { }
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[[branch(5.2)]] if (cond) cond = false;
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[[dont_flatten(3 + 7)]] switch(3) { case 3: break; }
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// other valid uses
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[[ unroll, dont_unroll, dependency_length(2) ]] while(cond) { }
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[ [ dont_flatten , branch ] ] switch(3) { case 3: break; }
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[
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// attribute
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[
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// here
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flatten
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]
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] if (cond) { } else { }
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[[ dependency_length(2), dependency_infinite ]] while(cond) { }
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}
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