• Top
  • Documentation
  • Books
  • Boolean-reasoning
  • Projects
    • Apt
    • Zfc
    • Acre
    • Milawa
    • Smtlink
    • Abnf
    • Vwsim
    • Isar
    • Wp-gen
    • Dimacs-reader
    • Pfcs
    • Legacy-defrstobj
    • Proof-checker-array
    • Soft
    • C
    • Farray
    • Rp-rewriter
    • Riscv
      • Semantics
        • Exec-bgeu
        • Exec-bltu
        • Exec-blt
        • Exec-bge
        • Exec-jalr
        • Exec-bne
        • Exec-beq
        • Exec-sra
        • Exec-op-imms-32
        • Exec-srl
        • Exec-branch
        • Exec-sll
        • Exec-op-imms64
        • Exec-op-imms32
        • Exec-op-imm-32
        • Exec-op-32
        • Exec-op
        • Exec-srlw
        • Exec-srliw
        • Exec-sraw
        • Exec-sraiw
        • Exec-sltiu
        • Exec-remuw
        • Exec-op-imm
        • Exec-jal
        • Exec-store
        • Exec-srli64
        • Exec-srli32
        • Exec-srai64
        • Exec-srai32
        • Exec-sllw
        • Exec-remw
        • Exec-load
        • Exec-divuw
        • Exec-addiw
        • Exec-xori
        • Exec-slti
        • Exec-slliw
        • Exec-remu
        • Exec-rem
        • Exec-divw
        • Exec-sw
        • Exec-slli64
        • Exec-slli32
        • Exec-ori
        • Exec-mulhsu
        • Exec-divu
        • Exec-andi
        • Exec-addi
        • Exec-sltu
        • Exec-slt
        • Exec-mulhu
        • Exec-div
        • Exec-auipc
        • Exec-addw
        • Exec-xor
        • Exec-mulw
        • Exec-mulh
        • Exec-lwu
        • Exec-and
        • Exec-subw
        • Exec-sub
        • Exec-sh
        • Exec-sd
        • Exec-sb
        • Exec-or
        • Exec-lhu
        • Exec-lh
        • Exec-ld
        • Exec-lbu
        • Exec-lb
        • Exec-mul
        • Exec-add
        • Exec-lw
        • Exec-lui
        • Eff-addr
        • Exec-instr
      • Instructions
      • Decoding
      • States
      • Encoding
      • Features
      • Rv32im
      • Rv64im
      • Execution
    • Instant-runoff-voting
    • Imp-language
    • Sidekick
    • Leftist-trees
    • Java
    • Taspi
    • Bitcoin
    • Des
    • Ethereum
    • X86isa
    • Sha-2
    • Yul
    • Zcash
    • Proof-checker-itp13
    • Regex
    • ACL2-programming-language
    • Json
    • Jfkr
    • Equational
    • Cryptography
    • Poseidon
    • Where-do-i-place-my-book
    • Axe
    • Bigmems
    • Builtins
    • Execloader
    • Aleo
    • Solidity
    • Paco
    • Concurrent-programs
    • Bls12-377-curves
  • Debugging
  • Std
  • Proof-automation
  • Community
  • Macro-libraries
  • ACL2
  • Interfacing-tools
  • Hardware-verification
  • Software-verification
  • Math
  • Testing-utilities

• Semantics

Eff-addr

Effective address for a load or store instruction [ISA:2.6].

Signature

(eff-addr rs1 imm stat feat) → addr

Arguments

rs1 — Guard (ubyte5p rs1).

imm — Guard (ubyte12p imm).

stat — Guard (statp stat).

feat — Guard (featp feat).

Returns

addr — Type (integerp addr).

We read an unsigned XLEN-bit integer from rs1; this is the base. We sign-extend the 12-bit immediate to XLEN bits; this is the offset. We return the sum of base and offset, as an integer; the functions to read and write memory use the low XLEN bits of this integer.

Definitions and Theorems

Function: eff-addr

(defun eff-addr (rs1 imm stat feat)
  (declare (xargs :guard (and (ubyte5p rs1)
                              (ubyte12p imm)
                              (statp stat)
                              (featp feat))))
  (declare (xargs :guard (stat-validp stat feat)))
  (let ((__function__ 'eff-addr))
    (declare (ignorable __function__))
    (b* ((base (read-xreg-unsigned (ubyte5-fix rs1)
                                   stat feat))
         (offset (loghead (feat->xlen feat)
                          (logext 12 (ubyte12-fix imm)))))
      (+ base offset))))

Theorem: integerp-of-eff-addr

(defthm integerp-of-eff-addr
  (b* ((addr (eff-addr rs1 imm stat feat)))
    (integerp addr))
  :rule-classes :rewrite)

Theorem: eff-addr-of-ubyte5-fix-rs1

(defthm eff-addr-of-ubyte5-fix-rs1
  (equal (eff-addr (ubyte5-fix rs1)
                   imm stat feat)
         (eff-addr rs1 imm stat feat)))

Theorem: eff-addr-ubyte5-equiv-congruence-on-rs1

(defthm eff-addr-ubyte5-equiv-congruence-on-rs1
  (implies (ubyte5-equiv rs1 rs1-equiv)
           (equal (eff-addr rs1 imm stat feat)
                  (eff-addr rs1-equiv imm stat feat)))
  :rule-classes :congruence)

Theorem: eff-addr-of-ubyte12-fix-imm

(defthm eff-addr-of-ubyte12-fix-imm
  (equal (eff-addr rs1 (ubyte12-fix imm)
                   stat feat)
         (eff-addr rs1 imm stat feat)))

Theorem: eff-addr-ubyte12-equiv-congruence-on-imm

(defthm eff-addr-ubyte12-equiv-congruence-on-imm
  (implies (acl2::ubyte12-equiv imm imm-equiv)
           (equal (eff-addr rs1 imm stat feat)
                  (eff-addr rs1 imm-equiv stat feat)))
  :rule-classes :congruence)

Theorem: eff-addr-of-stat-fix-stat

(defthm eff-addr-of-stat-fix-stat
  (equal (eff-addr rs1 imm (stat-fix stat) feat)
         (eff-addr rs1 imm stat feat)))

Theorem: eff-addr-stat-equiv-congruence-on-stat

(defthm eff-addr-stat-equiv-congruence-on-stat
  (implies (stat-equiv stat stat-equiv)
           (equal (eff-addr rs1 imm stat feat)
                  (eff-addr rs1 imm stat-equiv feat)))
  :rule-classes :congruence)

Theorem: eff-addr-of-feat-fix-feat

(defthm eff-addr-of-feat-fix-feat
  (equal (eff-addr rs1 imm stat (feat-fix feat))
         (eff-addr rs1 imm stat feat)))

Theorem: eff-addr-feat-equiv-congruence-on-feat

(defthm eff-addr-feat-equiv-congruence-on-feat
  (implies (feat-equiv feat feat-equiv)
           (equal (eff-addr rs1 imm stat feat)
                  (eff-addr rs1 imm stat feat-equiv)))
  :rule-classes :congruence)