CC1350: Left shift of negative values in SIMPLELINK-CC13X0-SDK_3.20.00.23

Tuze Kuyucu

Part Number: CC1350
Other Parts Discussed in Thread: SIMPLELINK-CC13X0-SDK

sys_ctrl.c:168:

HWREGH( ADI3_BASE + ADI_O_MASK8B + ( ADI_3_REFSYS_O_DCDCCTL1 * 2 )) = (( ADI_3_REFSYS_DCDCCTL1_VDDR_TRIM_SLEEP_M << 8 ) |
      (( vddrTrimSleep << ADI_3_REFSYS_DCDCCTL1_VDDR_TRIM_SLEEP_S ) & ADI_3_REFSYS_DCDCCTL1_VDDR_TRIM_SLEEP_M ));

setup_rom.c:218:

HWREGH( ADI3_BASE + ADI_O_MASK8B + ( ADI_3_REFSYS_O_DCDCCTL1 * 2 )) = (( ADI_3_REFSYS_DCDCCTL1_VDDR_TRIM_SLEEP_M << 8 ) |
(( i32VddrSleepTrim << ADI_3_REFSYS_DCDCCTL1_VDDR_TRIM_SLEEP_S ) & ADI_3_REFSYS_DCDCCTL1_VDDR_TRIM_SLEEP_M ));

In both cases the values vddrTrimSleep and i32VddrSleepTrim can be negative. The code itself is safe due to ADI_3_REFSYS_DCDCCTL1_VDDR_TRIM_SLEEP_S being 0, but static analysis tools still flag these lines. It would be nice to get this fixed in the next release.

over 4 years ago

0 Marie H over 4 years ago

TI__Guru 73361 points

Hi Tuze,

1. What version of the SimpleLink CC13x0 SDK are you using?

2. What example project is your application based on?

0 Tuze Kuyucu over 4 years ago in reply to Marie H

Prodigy 60 points

Hi Marie!

Sorry for not being clear enough. This exists in pretty much in every single version of your cc13xx SDK, I quoted the latest one I know about in the title of this post: SIMPLELINK-CC13X0-SDK_3.20.00.23.

You don't need to worry about the example project, but that your SDK has some code that are undefined in the C99 programming language spec, and would be good to fix.

0 Siri over 4 years ago in reply to Tuze Kuyucu

TI__Guru* 79361 points

Hi Tuze

I will try to have someone from the driverlib team comment on this.

Siri

0 IUsedToBeARealPerson (M-W) over 4 years ago in reply to Siri

TI__Guru 58425 points

Hi Tuze,

The trim value is either a positive or negative number but with a clear defined boundary. I assume that the analyze tool in question do not take the value boundaries into consideration. Could you comment on which tool you are using for the moment?

0 Tuze Kuyucu over 4 years ago in reply to IUsedToBeARealPerson (M-W)

Prodigy 60 points

Hi M-W

I am not sure how to be more explicit here.

Left shift of a negative value is undefined in C, do we agree?

0 IUsedToBeARealPerson (M-W) over 4 years ago in reply to Tuze Kuyucu

TI__Guru 58425 points

Absolutely, there is no question about this. This would mean that the behavior is device/vendor specific and you have to verify the behavior. I wanted to know which static analyzing tools you were using in order to look closer at your warning compared to the analyzing tools we use.

As for the code itself, I would assume a simple cast to unsigned before shifting would do.

0 Tuze Kuyucu over 4 years ago in reply to IUsedToBeARealPerson (M-W)

Prodigy 60 points

Thanks! It would be great if you guys can get this in the next release, as it is not nice to edit vendor code since that gives conflicts everytime there is a new release.

This was more of a bug report than a question, I am not sure how else to report it if there was another channel I should use please let me know.

0 IUsedToBeARealPerson (M-W) over 4 years ago in reply to Tuze Kuyucu

TI__Guru 58425 points

We will as Siri said bring it up with the responsible team in question. As for "bug reporting", you are correct in using E2E, this is the correct channel for anything concerning our SDK software deliveries!

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CC1350: Left shift of negative values in SIMPLELINK-CC13X0-SDK_3.20.00.23