PSOC6: correctly align hex files with split text sections

[vmedcy]

Description

When the original PSOC6 CM4 hex file contains unalinged text sections
that span through multiple intelhex segments, aligned segments (filled
with zeroes) overlap with the original data segments, resulting in
error thrown by ihex.merge(alignments, overlap='error').
Such hex file can be produced when the ELF is built with ARM MDK Compiler
with --split_sections option:
http://www.keil.com/support/man/docs/armcc/armcc_chr1359124944914.htm

Change the merge strategy to overlap='ignore', so that the overlapping
zero-filled segments are skipped.

Pull request type

[ ] Fix
[ ] Refactor
[X] Target update
[ ] Functionality change
[ ] Docs update1
[ ] Test update
[ ] Breaking change

Reviewers

Release Notes

[deepikabhavnani]

Split section is always enabled for ARM compiler, not sure why this issue was not seen earlier. Am I missing sometime here?

mbed-os/tools/profiles/develop.json

Line 29 in b088bd4

"common": ["-c", "--gnu", "-Otime", "--split_sections",

[bridadan]

I would defer to @vmedcy and @deepikabhavnani in this case, its a bit target-specific for me.

[bridadan]

I would defer to @vmedcy and @deepikabhavnani in this case, its a bit target-specific for me.

[vmedcy]

@deepikabhavnani:

Split section is always enabled for ARM compiler, not sure why this issue was not seen earlier

The issue with unaligned HEX segments was first observed by Cypress BLE development team that tried to include prebuilt BLE stack controller library in GCC_ARM build. The stack library was precompiled using ARM Compiler 5 (with --split_sections option), then linked with arm-none-eabi-gcc using standard mbed compile -t GCC_ARM. GCC linker, unlike armlink, cannot align split functions from object code produced by ARM compiler. PSOC6.py re-aligns the HEX file correctly with this PR applied.
ELF file is aligned correctly when all object code is compiled and linked with ARM Compiler.

[deepikabhavnani]

@vmedcy - Thanks for explanation

[deepikabhavnani]

👍

[deepikabhavnani]

👍

[0xc0170]

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[mbed-ci]

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