diff options
| -rw-r--r-- | src/rv32.tex | 7 | ||||
| -rw-r--r-- | src/rv64.tex | 6 |
2 files changed, 7 insertions, 6 deletions
diff --git a/src/rv32.tex b/src/rv32.tex index 7a676a4..b6885cb 100644 --- a/src/rv32.tex +++ b/src/rv32.tex @@ -569,7 +569,7 @@ bits with zeros. AUIPC (add upper immediate to {\tt pc}) is used to build {\tt pc}-relative addresses and uses the U-type format. AUIPC forms a 32-bit offset from the 20-bit U-immediate, filling in the lowest 12 bits with zeros, adds this offset -to the {\tt pc} of the AUIPC instruction, then places the result in register {\em rd}. +to the address of the AUIPC instruction, then places the result in register {\em rd}. \begin{commentary} The AUIPC instruction supports two-instruction sequences to access @@ -690,7 +690,8 @@ slots. \vspace{-0.1in} The jump and link (JAL) instruction uses the J-type format, where the J-immediate encodes a signed offset in multiples of -2 bytes. The offset is sign-extended and added to the {\tt pc} +2 bytes. The offset is sign-extended and added to the address of +the jump instruction to form the jump target address. Jumps can therefore target a $\pm$\wunits{1}{MiB} range. JAL stores the address of the instruction following the jump ({\tt pc}+4) into register {\em rd}. The standard @@ -848,7 +849,7 @@ enable macro-op fusion of the sequences:\linebreak All branch instructions use the B-type instruction format. The 12-bit B-immediate encodes signed offsets in multiples of 2 bytes. The offset is sign-extended and added -to the current {\tt pc} to give the target address. The +to the address of the branch instruction to give the target address. The conditional branch range is $\pm$\wunits{4}{KiB}. \vspace{-0.2in} diff --git a/src/rv64.tex b/src/rv64.tex index ef51e62..bde375c 100644 --- a/src/rv64.tex +++ b/src/rv64.tex @@ -139,11 +139,11 @@ places zero in the lowest 12 bits. The 32-bit result is sign-extended to 64 bits. AUIPC (add upper immediate to {\tt pc}) uses the same opcode as RV32I. -AUIPC (add upper immediate to {\tt pc}) is used to build {\tt +AUIPC is used to build {\tt pc}-relative addresses and uses the U-type format. AUIPC appends 12 low-order zero bits to the 20-bit U-immediate, sign-extends the result -to 64 bits, then adds it to the {\tt pc} and places the result in -register {\em rd}. +to 64 bits, adds it to the address of the AUIPC instruction, +then places the result in register {\em rd}. \subsubsection*{Integer Register-Register Operations} |