TM4C123GH6PM: 我用ccs6.2 配置的TM4C123GH6PM工程，我想设置ccs使得我写代码时 ，再输入几个字符后，会提示匹配 需要怎么配置呢。

Part Number: TM4C123GH6PM

这个问题怎么解决呢....

Thank you - now (maybe/hopefully) it is possible for 'native English speakers' to assist.

If you are asking, "Which of these 3 methods proves best for your specific use" - then the answer becomes, 'It depends.'

These 'optimization levels' usually center upon 'MCU Execution Speed' and/or 'MCU Code Size.'    And - such choice is made by the user - on a 'Case by Case Basis.'   Usually one finds it difficult to optimize (both) Speed & Code Size.    And helpfully - most usually (only one) of those two objectives is (really) required.

At times - such 'optimization' produces 'unanticipated consequences' - such as, 'Optimizing AWAY certain elements (especially variables) of your code!'    (i.e. that code and/or variable will then 'not' be 'acted upon!')    You should note that the Compiler (in its considered {sometimes inflated} opinion) makes such decisions 'on its own' - and (rarely) informs/advises of such action!    To be fair - there ARE coding practices you can adopt which, 'Limit such Compiler Intrusions.'

Your 'IDE' along w/some experimentation will increase your understanding of the various 'trade-offs' - resulting from each optimization level.     Again - there is 'NO Universal Optimization Level' - ideal for 'each/every' MCU application & implementation.    Often - it proves best to produce (otherwise) identical boards - but compiled w/different optimization settings - and then to provide sufficient 'operational time' to compare & contrast - which enables the recognition of 'best performer.'