[RISCV] Use uint64_t for Insn in getInstruction32 and getInstruction16. NFC #146619
Conversation
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
…6. NFC Insn is passed to decodeInstruction which is a template function based on the type of Insn. By using uint64_t we ensure only one version of decodeInstruction is created. This reduces the file size of RISCVDisassembler.cpp.o by ~25% in my local build. This should get even more size benefit than llvm#146593.
|
@llvm/pr-subscribers-backend-risc-v Author: Craig Topper (topperc) ChangesInsn is passed to decodeInstruction which is a template function based on the type of Insn. By using uint64_t we ensure only one version of decodeInstruction is created. This reduces the file size of RISCVDisassembler.cpp.o by ~25% in my local build. This should get even more size benefit than #146593. Full diff: https://github.com/llvm/llvm-project/pull/146619.diff 1 Files Affected:
diff --git a/llvm/lib/Target/RISCV/Disassembler/RISCVDisassembler.cpp b/llvm/lib/Target/RISCV/Disassembler/RISCVDisassembler.cpp
index 27e04c0cb1f8b..52061e96d0018 100644
--- a/llvm/lib/Target/RISCV/Disassembler/RISCVDisassembler.cpp
+++ b/llvm/lib/Target/RISCV/Disassembler/RISCVDisassembler.cpp
@@ -811,7 +811,9 @@ DecodeStatus RISCVDisassembler::getInstruction32(MCInst &MI, uint64_t &Size,
}
Size = 4;
- uint32_t Insn = support::endian::read32le(Bytes.data());
+ // Use uint64_t to match getInstruction48. decodeInstruction is templated
+ // on the Insn type.
+ uint64_t Insn = support::endian::read32le(Bytes.data());
for (const DecoderListEntry &Entry : DecoderList32) {
if (!Entry.haveContainedFeatures(STI.getFeatureBits()))
@@ -857,7 +859,9 @@ DecodeStatus RISCVDisassembler::getInstruction16(MCInst &MI, uint64_t &Size,
}
Size = 2;
- uint32_t Insn = support::endian::read16le(Bytes.data());
+ // Use uint64_t to match getInstruction48. decodeInstruction is templated
+ // on the Insn type.
+ uint64_t Insn = support::endian::read16le(Bytes.data());
for (const DecoderListEntry &Entry : DecoderList16) {
if (!Entry.haveContainedFeatures(STI.getFeatureBits()))
|
jurahul
approved these changes
Jul 2, 2025
lenary
approved these changes
Jul 2, 2025
|
Sorry, we didn't consider compiler code size at all when adding the 48-bit instructions. This is a nice improvement. |
|
LLVM Buildbot has detected a new failure on builder Full details are available at: https://lab.llvm.org/buildbot/#/builders/94/builds/8502 Here is the relevant piece of the build log for the reference |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Insn is passed to decodeInstruction which is a template function based on the type of Insn. By using uint64_t we ensure only one version of decodeInstruction is created. This reduces the file size of RISCVDisassembler.cpp.o by ~25% in my local build.
This should get even more size benefit than #146593.