tinygo/targets/cortex-m3.json

{
	"inherits": ["cortex-m"],
	"llvm-target": "thumbv7m-unknown-unknown-eabi",
	"cpu": "cortex-m3"
}
all: clean up Cortex-M target files In this commit I've moved all core-specific flags to files for that specific core. This is a bit of a cleanup (less duplicated JSON) but should also help in the future when core-specific changes are made, such as core specific build tags or when the FPU finally gets supported in TinyGo. Some notable specific changes: - I've removed floating point flags from the Teensy 3.6 target. The reason is that the FPU is not yet supported in TinyGo (in goroutine stack switching for example) and floating point numbers would only be supported by C files, not Go files (because the LLVM FPU feature flags aren't used). This would create an ABI mismatch across CGo. - I've added the "cpu":"cortex-m7" to the cortex-m7.json file to match the configuration for the Teensy 4.0. This implies a change to the nucleo-f722ze (because now it has its CPU field set). Somehow that reduces the code size, so it looks like a good change. I don't believe any of these changes should have any practical consequences. One issue I've found is in the Cortex-M33 target: it uses armv7m, which is incorrect: it should be armv8m. But the chip is backwards compatible so this should mostly work. Switching to armv8m led to a compilation failure because PRIMASK isn't defined, this may be an actual bug. 4 years ago			`{`
			`"inherits": ["cortex-m"],`
targets: match LLVM triple to the one Clang uses The target triples have to match mostly to be able to link LLVM modules. Linking LLVM modules is already possible (the triples already match), but testing becomes much easier when they match exactly. For macOS, I picked "macosx10.12.0". That's an old and unsupported version, but I had to pick _something_. Clang by default uses "macos10.4.0", which is much older. 3 years ago			`"llvm-target": "thumbv7m-unknown-unknown-eabi",`
targets: add CPU property everywhere This is for consistency with Clang, which always adds a CPU flag even if it's not specified in CFLAGS. This commit also adds some tests to make sure the Clang target-cpu matches the CPU property in the JSON files. This does have an effect on the generated binaries. The effect is very small though: on average just 0.2% increase in binary size, apparently because Cortex-M3 and Cortex-M4 are compiled a bit differently. However, when rebased on top of https://github.com/tinygo-org/tinygo/pull/2218 (minsize), the difference drops to -0.1% (a slight decrease on average). 3 years ago			`"cpu": "cortex-m3"`
all: clean up Cortex-M target files In this commit I've moved all core-specific flags to files for that specific core. This is a bit of a cleanup (less duplicated JSON) but should also help in the future when core-specific changes are made, such as core specific build tags or when the FPU finally gets supported in TinyGo. Some notable specific changes: - I've removed floating point flags from the Teensy 3.6 target. The reason is that the FPU is not yet supported in TinyGo (in goroutine stack switching for example) and floating point numbers would only be supported by C files, not Go files (because the LLVM FPU feature flags aren't used). This would create an ABI mismatch across CGo. - I've added the "cpu":"cortex-m7" to the cortex-m7.json file to match the configuration for the Teensy 4.0. This implies a change to the nucleo-f722ze (because now it has its CPU field set). Somehow that reduces the code size, so it looks like a good change. I don't believe any of these changes should have any practical consequences. One issue I've found is in the Cortex-M33 target: it uses armv7m, which is incorrect: it should be armv8m. But the chip is backwards compatible so this should mostly work. Switching to armv8m led to a compilation failure because PRIMASK isn't defined, this may be an actual bug. 4 years ago			`}`