• Top
  • Documentation
  • Books
  • Boolean-reasoning
  • Projects
  • Debugging
  • Std
  • Proof-automation
  • Macro-libraries
  • ACL2
  • Interfacing-tools
  • Hardware-verification
  • Software-verification
    • Kestrel-books
    • X86isa
      • Program-execution
      • Sdm-instruction-set-summary
      • Tlb
      • Running-linux
      • Introduction
      • Asmtest
      • X86isa-build-instructions
      • Publications
      • Contributors
      • Machine
        • X86isa-state
        • Syscalls
        • Cpuid
        • Linear-memory
        • Rflag-specifications
        • Characterizing-undefined-behavior
        • Top-level-memory
        • App-view
        • X86-decoder
        • Physical-memory
        • Decoding-and-spec-utils
          • Read-operands-and-write-results
          • Effective-address-computations
          • Select-operand-size
          • Instruction-pointer-operations
          • Stack-pointer-operations
          • Select-segment-register
          • Prefix-modrm-sib-decoding
          • Select-address-size
          • Rex-byte-from-vex-prefixes
          • Check-instruction-length
          • Error-objects
          • Rip-guard-okp
          • Sib-decoding
        • Instructions
        • Register-readers-and-writers
        • X86-modes
        • Segmentation
        • Other-non-deterministic-computations
        • Environment
        • Paging
      • Implemented-opcodes
      • To-do
      • Proof-utilities
      • Peripherals
      • Model-validation
      • Modelcalls
      • Concrete-simulation-examples
      • Utils
      • Debugging-code-proofs
    • Axe
    • Execloader
  • Math
  • Testing-utilities

• Decoding-and-spec-utils

Rip-guard-okp

Size constraints on a memory address of some instruction byte

Signature

(rip-guard-okp proc-mode rip) → *

This function specifies the maximum size of a memory address that points to some instruction byte in a certain mode of operation. We usually use this function to specify the guard on start-rip or temp-rip --- that way, we can put in suitable type declarations in our specification functions.

This function doesn't really specify whether a memory address that points to some instruction byte is valid or not --- that notion is much more complicated; see canonical-address-p, ea-to-la, and instruction-pointer-operations for details.

Definitions and Theorems

Function: rip-guard-okp

(defun rip-guard-okp (proc-mode rip)
  (declare (type (integer 0 4) proc-mode)
           (type (signed-byte 48) rip))
  (let ((__function__ 'rip-guard-okp))
    (declare (ignorable __function__))
    (if (equal proc-mode 0)
        (signed-byte-p 48 rip)
      (unsigned-byte-p 32 rip))))

Theorem: rip-guard-okp-equiv-for-non-64-bit-modes

(defthm rip-guard-okp-equiv-for-non-64-bit-modes
  (implies (and (rip-guard-okp proc-mode-1 rip)
                (not (equal proc-mode-1 0))
                (not (equal proc-mode-2 0)))
           (rip-guard-okp proc-mode-2 rip)))

Theorem: rip-guard-okp-for-64-bit-modep

(defthm rip-guard-okp-for-64-bit-modep
  (equal (rip-guard-okp 0 rip)
         (signed-byte-p 48 rip)))

Theorem: rip-guard-okp-for-compatibility-mode

(defthm rip-guard-okp-for-compatibility-mode
  (equal (rip-guard-okp 1 rip)
         (unsigned-byte-p 32 rip)))