Add target for Big-endian ARM Cortex-R4F/R5F MCUs #50813
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The ARM Real-Time (‘R’) profile provides high-performing processors for safety-critical environments.
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| ENV TARGET=armebv7r-none-eabihf | ||
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| ENV CC_armebv7r_none_eabihf=armeb-eabi-gcc \ | ||
| CFLAGS_armebv7r_none_eabihf="-mthumb -march=armv7-r" |
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To match this rust target, you want -marm instead of -mthumb.
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Cortex-R has ARM+Thumb instruction (dual mode). Wake-up in ARM mode and can use Thumb instr. So here armv7-r select ARM mode, -mthumb extend support for Thumb.
The same logic also in LLVM: the triple armebv7r-none-eabihf and the feature +thumb2.
This is a working Makefile that use -mthumb -march=armv7-r and this a working JSON.
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Yes, that's correct, it supports Arm and Thumb state. The question is what you want the default for this target to be? -mthumb and +thumb2 are not equivalent, +thumb2 does nothing because it's already Armv7. -mthumb is equivalent to using llvm_target thumbebv7r-none-eabihf or adding +thumb-mode to armebv7r-none-eabihf.
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Ahh ok. Default shall be Arm. I'll move to -marm removing +thumb2 too.
I'll test again on target (TI TMS570LS3137) in the afternoon. Thanks.
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To confirm, we've matched naming so far sort of with Debian but otherwise just tried to find preexisting conventions to name targets. In that sense, there's precedent for this name? |
- remove +thumb2 that has not effect - remove -mthumb Tested on TMS570LS3137
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Updated with comments from @parched |
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@bors: r+ |
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📌 Commit 4897093 has been approved by |
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Add target for Big-endian ARM Cortex-R4F/R5F MCUs The ARM Real-Time (‘R’) profile provides high-performing processors for safety-critical environments. Cortex-R has ARM, Thumb instruction whereas Cortex-M makes use of Thumb only. CI/Dockerfile is intentionally in the `disabled` folder.
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☀️ Test successful - status-appveyor, status-travis |
The ARM Real-Time (‘R’) profile provides high-performing processors for safety-critical environments.
Cortex-R has ARM, Thumb instruction whereas Cortex-M makes use of Thumb only.
CI/Dockerfile is intentionally in the
disabledfolder.