Peeking Into Your Compiler
summary
Shows concrete ways to inspect GCC output: run the driver with -v to reproduce cc1/cc1plus invocations, use -E to see preprocessed input, -pipe and -save-temps to keep intermediate files, and -fdump- to get gimple/RTL dumps* (GCC has ~50–70 middle-end passes and historically produced ~192 dump files for one build). Explains LTO internals (WPA then partitioned backend compilations, fat LTO doubles compile time), PGO, NVPTX offload support (GCC 10 AMD/GCN backend), and examples where range/VRP-driven optimizations expose undefined behavior.
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chapters (16)
- 0:00Start
- 3:34Code Generator
- 6:30Preprocessor
- 7:30Precompiled Headers
- 10:06Compiled Unit
- 23:21Lto
- 25:59Modes of Lto
- 31:58Inlining
- 36:40How Do You Get the Highest Compile Speed
- 41:11Extensions
- 51:17Pre-Process C Source Code
- 1:03:04Ternary Operator
- 1:05:28Graphical Output
- 1:07:02Optimized Dump
- 1:14:48Vrp Dump
- 1:22:08Overview
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