RFR: JDK-8301506: Replace NULL with nullptr in os_cpu/linux_ppc

[Johan Sjölen]

On Tue, 31 Jan 2023 11:41:59 GMT, Johan Sjölen <jsjolen at openjdk.org> wrote:

> Hi, this PR changes all occurrences of NULL to nullptr for the subdirectory os_cpu/linux_ppc. Unfortunately the script that does the change isn't perfect, and so we
> need to comb through these manually to make sure nothing has gone wrong. I also review these changes but things slip past my eyes sometimes.
> 
> Here are some typical things to look out for:
> 
> 1. No changes but copyright header changed (probably because I reverted some changes but forgot the copyright).
> 2. Macros having their NULL changed to nullptr, these are added to the script when I find them. They should be NULL.
> 3. nullptr in comments and logs. We try to use lower case "null" in these cases as it reads better. An exception is made when code expressions are in a comment.
> 
> An example of this:
> 
> ```c++
> // This function returns null
> void* ret_null();
> // This function returns true if *x == nullptr
> bool is_nullptr(void** x);
> 
> 
> Note how `nullptr` participates in a code expression here, we really are talking about the specific value `nullptr`.
> 
> Thanks!

One small fix.

src/hotspot/os_cpu/linux_ppc/javaThread_linux_ppc.cpp line 73:

> 71:       // The found frame does not have a valid frame pointer.
> 72:       // Bail out because this will create big trouble later on, either
> 73:       //  - when using istate, calculated as (null - ijava_state_size) or

nullptr

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PR: https://git.openjdk.org/jdk/pull/12335