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[www] fix the rest of the identified spelling mistakes
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isuckatcs committed Jul 30, 2024
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48 changes: 24 additions & 24 deletions www/constexpr.html
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Expand Up @@ -55,17 +55,17 @@ <h1>Compile Time Known Values</h1>
return 2 + 3 * 4;
}</code></pre>
<p>
In the above function it can be calculated that the returned
value is <code>14</code> during compilation, so instead of
emitting the addition and the multiplication to the IR, it
is enough to emit only a single constant.
In the above function, it can be calculated that the
returned value is <code>14</code> during compilation, so
instead of emitting the addition and the multiplication to
the IR, it is enough to emit only a single constant.
</p>
<h2>A Tree-walk Interpreter</h2>
<p>
There are multiple solutions for constant expression
evaluation, but one of the most widespread is the tree-walk
interpreter. It is built on the observation that the post
order evaluation of the AST yields the result of the
interpreter. It is built on the observation that the
post-order evaluation of the AST yields the result of the
expression.
</p>
<pre><code> ┌───┐
Expand All @@ -82,14 +82,14 @@ <h2>A Tree-walk Interpreter</h2>
post order and evaluates what it sees.
</p>
<p>
Inside the compiler it can be invoked on resolved
Inside the compiler, it can be invoked on resolved
expressions on demand. Since valid expressions can only
evaluate to numbers, the interpreter returns an
<code>std::optional&lt;double></code>, which holds the
result if it managed to evaluate the expression.
</p>
<p>
For the evaluation of some operators it matters if side
For the evaluation of some operators, it matters if side
effects are allowed or not, so the interpreter also provides
an option to change how side effects are treated.
</p>
Expand All @@ -100,7 +100,7 @@ <h2>A Tree-walk Interpreter</h2>
};</code></pre>
<p>
The simplest expression to evaluate is the number literal,
which simply evaluates to it's already known value.
which simply evaluates to its already known value.
</p>
<pre><code>std::optional&lt;double>
ConstantExpressionEvaluator::evaluate(const ResolvedExpr &expr,
Expand Down Expand Up @@ -146,8 +146,8 @@ <h2>A Tree-walk Interpreter</h2>
...
}</code></pre>
<p>
First the operand is evaluated, and if it is a known value,
either it's numeric or logical value is negated depending on
First, the operand is evaluated, and if it is a known value,
either its numeric or logical value is negated depending on
the operator.
</p>
<pre><code>std::optional&lt;double> ConstantExpressionEvaluator::evaluateUnaryOperator(
Expand Down Expand Up @@ -188,13 +188,13 @@ <h2>Handling Side Effects</h2>
<code>return sideEffect() || 1;</code> even though it's
known at compile time that the condition is always true,
replacing the statement with <code>return 1;</code> would
completely eliminate the side effect.
eliminate the side effect.
</p>
<p>
In other cases such as
<code>if sideEffect() || 1 { ... }</code> the compiler might
wants to reason about whether the condition is always true
or not. In these cases the side effect doesn't matter as the
want to reason about whether the condition is always true or
not. In these cases, the side effect doesn't matter as the
condition is not going to be replaced with a different
expression.
</p>
Expand Down Expand Up @@ -244,7 +244,7 @@ <h2>Handling Side Effects</h2>
<p>
If both the LHS and the RHS are known, but none of them is
<code>true</code>, the result is <code>false</code>. In
every other case the result cannot be calculated in compile
every other case, the result cannot be calculated in compile
time.
</p>
<pre><code>std::optional&lt;double> ConstantExpressionEvaluator::evaluateBinaryOperator(
Expand Down Expand Up @@ -292,7 +292,7 @@ <h2>Handling Side Effects</h2>
...
}</code></pre>
<p>
For the rest of the binary operators if both of their sides
For the rest of the binary operators, if both of their sides
are known in compile time, the respective operation is
performed on their values.
</p>
Expand Down Expand Up @@ -329,9 +329,9 @@ <h2>Handling Side Effects</h2>
<h2>Storing the Result</h2>
<p>
The <code>ResolvedExpr</code> node is equipped with the
capability of storing it's compile time known value, so that
capability of storing its compile-time known value so that
it can be reused later without recalculation for further
reasoning about the semantic of the source file and more
reasoning about the semantics of the source file and more
efficient code generation.
</p>
<p>
Expand Down Expand Up @@ -372,7 +372,7 @@ <h2>Storing the Result</h2>
<p>
With the ability to store the result, the
<code>evaluate()</code> method can be made more efficient by
checking whether the given expression already has it's value
checking whether the given expression already has its value
calculated and returning that value immediately.
</p>
<pre><code>std::optional&lt;double>
Expand All @@ -384,8 +384,8 @@ <h2>Storing the Result</h2>
}</code></pre>
<p>
The same optimization can also be used during code
generation, so that instead of a series of instructions,
only a constant value is generated.
generation so that instead of a series of instructions, only
a constant value is generated.
</p>
<pre><code>llvm::Value *Codegen::generateExpr(const ResolvedExpr &expr) {
if (auto val = expr.getConstantValue())
Expand All @@ -403,10 +403,10 @@ <h2>Calling the Interpreter</h2>
...
};</code></pre>
<p>
One of such cases is calculating the value of an argument
passed to a function. Since the expression is expected to be
One such case is calculating the value of an argument passed
to a function. Since the expression is expected to be
replaced with a constant value, the
<code>allowSideEffects</code> option is set to be
<code>allowSideEffects</code> option is set be
<code>false</code>.
</p>
<pre><code>std::unique_ptr&lt;ResolvedCallExpr> Sema::resolveCallExpr(const CallExpr &call) {
Expand Down
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