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@@ -1643,15 +1643,19 @@ example:
``speculative_load_hardening``
This attribute indicates that
`Speculative Load Hardening <https://llvm.org/docs/SpeculativeLoadHardening.html>`_
- should be enabled for the function body.
-
- Speculative Load Hardening is a best-effort mitigation against
- information leak attacks that make use of control flow
- miss-speculation - specifically miss-speculation of whether a branch
- is taken or not. Typically vulnerabilities enabling such attacks are
- classified as "Spectre variant #1". Notably, this does not attempt to
- mitigate against miss-speculation of branch target, classified as
- "Spectre variant #2" vulnerabilities.
+ should be enabled for the function body. This is a best-effort attempt to
+ mitigate all known speculative execution information leak vulnerabilities
+ that are based on the fundamental principles of modern processors'
+ speculative execution. These vulnerabilities are classified as "Spectre
+ variant #1" vulnerabilities typically. Notably, this does not attempt to
+ mitigate any vulnerabilities where the speculative execution and/or
+ prediction devices of specific processors can be *completely* undermined
+ (such as "Branch Target Injection", a.k.a, "Spectre variant #2"). Instead,
+ this is a target-independent request to harden against the completely
+ generic risk posed by speculative execution to incorrectly load secret data,
+ making it available to some micro-architectural side-channel for information
+ leak. For a processor without any speculative execution or predictors, this
+ is expected to be a no-op.
When inlining, the attribute is sticky. Inlining a function that carries
this attribute will cause the caller to gain the attribute. This is intended
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