Duplication In Real World Projects

COMDAT duplication

The following charts show the number of duplicated COMDAT instances found in the object files for large, real-world, C++ projects. In each case, the projects' object files were scanned to discover the set of COMDAT instances. These were then matched according to the normal rules followed by the static linker. For each name, the number of instances generated by the compiler and discarded by the linker was counted. The size of each instance is captured to give an indication of the compile-time cost of the code-generation cost.

Title	No. Instances Generated	No. Instances Discarded	Discarded (%)
Chromium	577397	576223	99.80
Clang+LLVM 3.7	52554	51766	98.50

LLVM

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Chrome

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