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git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@116993 91177308-0d34-0410-b5e6-96231b3b80d8
27 lines
1.5 KiB
Plaintext
27 lines
1.5 KiB
Plaintext
* Writing out ELF files is close to working but the following needs to
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be examined more closely:
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- ELF files are written with the wrong E_MACHINE value because
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ELFObjectWriter::WriteHeader function does not yet support
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target specific E_MACHINE values.
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- ELF relocation records are incorrect because the function
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ELFObjectWriter::RecordRelocation is hard coded for X86/X86-64.
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- Relocations use 2-byte / 4-byte to terminology in reference to
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the size of the immediate value being changed. The Xilinx
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terminology seems to be (???) 4-byte / 8-byte in reference
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to the number of bytes of instructions that are being changed.
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- BRLID and like instructions are always assumed to use a 4-byte
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immediate value for the relocation and BEQID and like instructions
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are always assumed to use a 2-byte immediate value for the relocation.
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I think this means that conditional branches like BEQID can only
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branch += 32768 bytes (~8192 instructions). We should allow conditional
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branches to use 4-byte relocations but I'm not sure how to do that
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right now.
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* Code generation seems to work relatively well now but the following
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needs to be examined more closely:
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- The stack layout needs to be examined to make sure it meets
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the standard, especially in regards to var arg functions.
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- The delay slot filler is ad hoc but seems to work. Load and
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store instructions were prevented from being moved to delay
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slots but I'm not sure that is necessary.
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