[FIPS 2025 CHERRYPICK] Fix FIPS delocator handling of floating-point immediates on aarch64#3255
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justsmth merged 1 commit intoMay 15, 2026
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…ws#3029) Addresses aws#3028 When GCC 15 compiles the FIPS module at `-O3` on aarch64, it emits `fmov` instructions with floating-point immediates (e.g. `fmov v8.4s, so it parses `#2.0e+0` as the integer `#2` followed by what it thinks is a symbol reference `.0e`. This gets turned into a redirector (`.Lbcm_redirector_.0e`), producing invalid assembly. This change fixes the issue in two ways: - **Grammar fix**: Adds a floating-point immediate alternative to the `RegisterOrConstant` rule in `delocate.peg`, so values like `#2.0e+0` are parsed as a single token. - **Pass-through**: Adds `fmov` to the special-case instruction list in `processAarch64Instruction()`. Since `fmov` only operates on registers and immediates (never memory), it never needs delocating and can safely be written through unchanged. The GCC 15 + FIPS exclusion in `arm-gcc-tests` CI is also removed now that the underlying issue is resolved. The `delocate.peg.go` file is regenerated from the grammar using the `peg` tool. The grammar change is the one line in `delocate.peg`; the rest of that file is mechanical. - Added 6 test cases to `testdata/aarch64-Basic/in.s` covering float immediates with exponent notation, simple decimals, negative values, fractional values, scalar forms, and register-to-register `fmov`. - All 19 existing delocator tests continue to pass. - Re-enabled the `arm-gcc-tests` CI matrix entry for GCC 15 + FIPS on arm64 which will validate the end-to-end build. By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license and the ISC license. (cherry picked from commit 7b2a86c)
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torben-hansen
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May 14, 2026
Codecov Report✅ All modified and coverable lines are covered by tests. Additional details and impacted files@@ Coverage Diff @@
## fips-2025-09-12-lts #3255 +/- ##
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- Coverage 78.77% 78.75% -0.02%
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Files 667 667
Lines 113386 113386
Branches 16085 16103 +18
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- Hits 89318 89299 -19
- Misses 23274 23293 +19
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justsmth
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May 15, 2026
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When GCC 15 compiles the FIPS module at
-O3on aarch64, it emitsfmovinstructions with floating-point immediates (e.g.fmov v8.4s, so it parses#2.0e+0as the integer#2followed by what it thinks is a symbol reference.0e. This gets turned into a redirector (.Lbcm_redirector_.0e`), producing invalid assembly.This change fixes the issue in two ways:
RegisterOrConstantrule indelocate.peg, so values like#2.0e+0are parsed as a single token.fmovto the special-case instruction list inprocessAarch64Instruction(). Sincefmovonly operates on registers and immediates (never memory), it never needs delocating and can safely be written through unchanged.The GCC 15 + FIPS exclusion in
arm-gcc-testsCI is also removed now that the underlying issue is resolved.The
delocate.peg.gofile is regenerated from the grammar using thepegtool. The grammar change is the one line indelocate.peg; the rest of that file is mechanical.testdata/aarch64-Basic/in.scovering float immediates with exponent notation, simple decimals, negative values, fractional values, scalar forms, and register-to-registerfmov.arm-gcc-testsCI matrix entry for GCC 15 + FIPS on arm64 which will validate the end-to-end build.By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license and the ISC license.
(cherry picked from commit 7b2a86c)