Initial gcc toolchain configuration for the lowRISC compiler. #1
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Things to discuss:
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| ) | ||
| if architecture == 'rv32imc': | ||
| # TODO(cfrantz): why do I have to do this? Seems the lowRISC gcc | ||
| # doesn't support `-mfpu`, `-mfloat-abi` or `-mlittle-endian`. |
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-mlittle-endian should work (at least it should if we update gcc). AFAICT the other flags are arm specific and aren't defined for other targets. The flag definitions should probably be moved into arch-specific code.
constraints/cpu/BUILD
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| constraint_value( | ||
| # Based on the current riscv64 consrtaint in platforms, I wonder | ||
| # if this should be `riscv32` or `rv32imc`. | ||
| name = "rv32imc", |
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I'm leaning towards keeping rv32imc. It looks like the generic arm target is slated for removal and there are a bunch of more specific 32-bit arm targets. riscv64 is probably geared towards the non-embedded use case.
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Based on bazelbuild/platforms#30, riscv32 is the appropriate high-level cpu descriptor. In fact, the change has already been applied by Google's copybara automation to Google internal copy of the platforms repo.
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To be consistent with bazelbuild/platforms#30, I've renamed the cpu to |
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I think we should commit this change as-is to move the bazel work foward. I have opened https://github.com/silvergasp/bazel-embedded/issues/37 with upstream to try to get feedback on the proper approach to integrating compiler/feature flags into a "user-serviceable" part of the bazel-embedded repo. Until we have that understanding, its fine to live with the |
SGTM. Feel free to commit this. |
| "defs.bzl", | ||
| """ | ||
| SYSTEM_INCLUDE_COMMAND_LINE = {} | ||
| SYSTEM_INCLUDE_PATHS= {} |
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Fixed. These two formatting errors also exist in the file I copied this from (gcc_arm_none_repository.bzl)
| """ | ||
| filegroup( | ||
| name = "all", | ||
| srcs = glob(["**/*"],exclude=["**/*.html","**/*.pdf"]), |
Configure lowrisc_toolchain_rv32imc for use by the OpenTitan project. Signed-off-by: Chris Frantz <cfrantz@google.com>
1. Deliver per-device flags to the GccEmbeddedFeatures function. 2. Turn off some per-feature compiler/linker flags. Need to find a better way to do this. Signed-off-by: Chris Frantz <cfrantz@google.com>
This naming is consistent with bazel's `platforms` which names high-level cpu architectures but not architecture details or cpu features. Signed-off-by: Chris Frantz <cfrantz@google.com>
) Initial toolchain definition for riscv32 1. Configure lowrisc_toolchain_rv32imc for use by the OpenTitan project. 2. Deliver per-device flags to the GccEmbeddedFeatures function. 3. Turn off some per-feature compiler/linker flags. Need to find a better way to do this. Signed-off-by: Chris Frantz <cfrantz@google.com>
) Initial toolchain definition for riscv32 1. Configure lowrisc_toolchain_rv32imc for use by the OpenTitan project. 2. Deliver per-device flags to the GccEmbeddedFeatures function. 3. Turn off some per-feature compiler/linker flags. Need to find a better way to do this. Signed-off-by: Chris Frantz <cfrantz@google.com>
Configure lowrisc_toolchain_rv32imc for use by the OpenTitan project.