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@@ -2642,7 +2642,7 @@ instructions, so we focus on the comparison and jump instructions.
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\Arg &::=& \ldots \mid (\key{byte-reg}\; \itm{register}) \\
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\Instr &::=& \ldots \mid (\key{andq} \; \Arg\; \Arg) \mid (\key{notq} \; \Arg)\\
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&\mid& (\key{cmpq} \; \Arg\; \Arg) \mid (\key{sete} \; \Arg)
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- \mid (\key{movzx}\;\Arg\;\Arg) \\
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+ \mid (\key{movzbq}\;\Arg\;\Arg) \\
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&\mid& (\key{jmp} \; \itm{label}) \mid (\key{je} \; \itm{label}) \mid
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(\key{label} \; \itm{label}) \\
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x86_1 &::= & (\key{program} \;\itm{info} \; \Instr^{+})
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@@ -2664,7 +2664,7 @@ its destination depending on whether the comparison came out as equal
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or not, respectively. The \key{sete} instruction has an annoying quirk
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in that its destination argument must be single byte register, such as
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\code{al}, which is part of the \code{rax} register. Thankfully, the
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-\key{movzx} instruction can then be used to move from a single byte
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+\key{movzbq} instruction can then be used to move from a single byte
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register to a normal 64-bit register.
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The \key{jmp} instruction jumps to the instruction after the indicated
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@@ -2703,7 +2703,7 @@ $\Rightarrow$
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\begin{lstlisting}
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(cmpq |$\Arg_1$| |$\Arg_2$|)
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(sete (byte-reg al))
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-(movzx (byte-reg al) |$\itm{lhs}$|)
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+(movzbq (byte-reg al) |$\itm{lhs}$|)
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\end{lstlisting}
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\end{minipage}
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\end{tabular} \\
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@@ -2767,7 +2767,7 @@ Many of the new instructions, such as the logical operations, can be
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handled in the same way as the arithmetic instructions. Thus, if your
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code was already quite general, it will not need to be changed to
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handle the logical operations. If not, I recommend that you change
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-your code to be more general. The \key{movzx} instruction should be
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+your code to be more general. The \key{movzbq} instruction should be
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handled like the \key{movq} instruction. The \key{if} statement is
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straightfoward to handle because we stored the live-after sets for the
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two branches in the AST node as described above. Here we just need to
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@@ -2854,7 +2854,7 @@ $\Downarrow$
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(movq (reg rax) (var t.1))
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(cmpq (int 1) (var t.1))
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(sete (byte-reg al))
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- (movzx (byte-reg al) (var t.2))
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+ (movzbq (byte-reg al) (var t.2))
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(if (var t.2)
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((movq (int 42) (var if.1)))
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((movq (int 0) (var if.1))))
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@@ -2867,7 +2867,7 @@ $\Downarrow$
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(movq (reg rax) (reg rcx))
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(cmpq (int 1) (reg rcx))
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(sete (byte-reg al))
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- (movzx (byte-reg al) (reg rcx))
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+ (movzbq (byte-reg al) (reg rcx))
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(if (reg rcx)
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((movq (int 42)
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(reg rbx)))
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@@ -2888,7 +2888,7 @@ _main:
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movq %rax, %rcx
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cmpq $1, %rcx
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sete %al
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- movzx %al, %rcx
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+ movzbq %al, %rcx
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cmpq $0, %rcx
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je else1326
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movq $42, %rbx
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Jeremy Siek