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Remove the comment "Constants must always have an initial value.", which 

is incorrect.  Fix some formatting nastiness.

llvm-svn: 12223
This commit is contained in:
Chris Lattner 2004-03-08 16:49:10 +00:00
parent d91e676700
commit b16526108c
1 changed files with 41 additions and 25 deletions
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66
llvm/docs/LangRef.html
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@ -623,45 +623,61 @@ external (i.e., lacking any linkage declarations), they are accessible
outside of the current module. It is illegal for a function <i>declaration</i>
to have any linkage type other than "externally visible".</a></p>
</div>
<!-- ======================================================================= -->
<div class="doc_subsection"> <a name="globalvars">Global Variables</a> </div>
<div class="doc_subsection">
<a name="globalvars">Global Variables</a>
</div>
<div class="doc_text">
<p>Global variables define regions of memory allocated at compilation
time instead of run-time. Global variables may optionally be
initialized. A variable may be defined as a global "constant", which
indicates that the contents of the variable will never be modified
(opening options for optimization). Constants must always have an
initial value.</p>
(opening options for optimization).</p>
<p>As SSA values, global variables define pointer values that are in
scope (i.e. they dominate) for all basic blocks in the program. Global
variables always define a pointer to their "content" type because they
describe a region of memory, and all memory objects in LLVM are
accessed through pointers.</p>
</div>
<!-- ======================================================================= -->
<div class="doc_subsection"> <a name="functionstructure">Functions</a> </div>
<div class="doc_text">
<p>LLVM function definitions are composed of a (possibly empty)
argument list, an opening curly brace, a list of basic blocks, and a
closing curly brace. LLVM function declarations are defined with the "<tt>declare</tt>"
keyword, a function name, and a function signature.</p>
<p>A function definition contains a list of basic blocks, forming the
CFG for the function. Each basic block may optionally start with a
label (giving the basic block a symbol table entry), contains a list of
instructions, and ends with a <a href="#terminators">terminator</a>
instruction (such as a branch or function return).</p>
<p>The first basic block in program is special in two ways: it is
immediately executed on entrance to the function, and it is not allowed
to have predecessor basic blocks (i.e. there can not be any branches to
the entry block of a function). Because the block can have no
predecessors, it also cannot have any <a href="#i_phi">PHI nodes</a>.</p>
<p>
LLVM functions are identified by their name and type signature. Hence, two
functions with the same name but different parameter lists or return values
are considered different functions, and LLVM will resolves references to each
appropriately.
</p>
<div class="doc_subsection">
<a name="functionstructure">Functions</a>
</div>
<div class="doc_text">
<p>LLVM function definitions are composed of a (possibly empty) argument list,
an opening curly brace, a list of basic blocks, and a closing curly brace. LLVM
function declarations are defined with the "<tt>declare</tt>" keyword, a
function name, and a function signature.</p>
<p>A function definition contains a list of basic blocks, forming the CFG for
the function. Each basic block may optionally start with a label (giving the
basic block a symbol table entry), contains a list of instructions, and ends
with a <a href="#terminators">terminator</a> instruction (such as a branch or
function return).</p>
<p>The first basic block in program is special in two ways: it is immediately
executed on entrance to the function, and it is not allowed to have predecessor
basic blocks (i.e. there can not be any branches to the entry block of a
function). Because the block can have no predecessors, it also cannot have any
<a href="#i_phi">PHI nodes</a>.</p>
<p>LLVM functions are identified by their name and type signature. Hence, two
functions with the same name but different parameter lists or return values are
considered different functions, and LLVM will resolves references to each
appropriately.</p>
</div>
<!-- *********************************************************************** -->
<div class="doc_section"> <a name="instref">Instruction Reference</a> </div>
<!-- *********************************************************************** -->