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Diffstat (limited to 'gcc/doc/gimple.texi')
| -rw-r--r-- | gcc/doc/gimple.texi | 88 |
1 files changed, 86 insertions, 2 deletions
diff --git a/gcc/doc/gimple.texi b/gcc/doc/gimple.texi index 984f00bd65a..5e217a772da 100644 --- a/gcc/doc/gimple.texi +++ b/gcc/doc/gimple.texi @@ -333,6 +333,7 @@ The following table briefly describes the GIMPLE instruction set. @item @code{GIMPLE_CALL} @tab x @tab x @item @code{GIMPLE_CATCH} @tab x @tab @item @code{GIMPLE_COND} @tab x @tab x +@item @code{GIMPLE_DEBUG} @tab x @tab x @item @code{GIMPLE_EH_FILTER} @tab x @tab @item @code{GIMPLE_GOTO} @tab x @tab x @item @code{GIMPLE_LABEL} @tab x @tab x @@ -452,8 +453,8 @@ becomes The same rule holds for arguments to a @code{GIMPLE_CALL}. -The target of an assignment is usually a variable, but can also be an -@code{INDIRECT_REF} or a compound lvalue as described below. +The target of an assignment is usually a variable, but can also be a +@code{MEM_REF} or a compound lvalue as described below. @menu * Compound Expressions:: @@ -664,6 +665,11 @@ Return true if t is a valid expression to use as the function called by a @code{GIMPLE_CALL}. @end deftypefn +@deftypefn {GIMPLE function} is_gimple_mem_ref_addr (tree t) +Return true if t is a valid expression to use as first operand +of a @code{MEM_REF} expression. +@end deftypefn + @deftypefn {GIMPLE function} is_gimple_constant (tree t) Return true if t is a valid gimple constant. @end deftypefn @@ -902,6 +908,7 @@ Return a deep copy of statement @code{STMT}. * @code{GIMPLE_CALL}:: * @code{GIMPLE_CATCH}:: * @code{GIMPLE_COND}:: +* @code{GIMPLE_DEBUG}:: * @code{GIMPLE_EH_FILTER}:: * @code{GIMPLE_LABEL}:: * @code{GIMPLE_NOP}:: @@ -1392,6 +1399,83 @@ Set the conditional @code{COND_STMT} to be of the form 'if (1 == 0)'. Set the conditional @code{COND_STMT} to be of the form 'if (1 == 1)'. @end deftypefn +@node @code{GIMPLE_DEBUG} +@subsection @code{GIMPLE_DEBUG} +@cindex @code{GIMPLE_DEBUG} +@cindex @code{GIMPLE_DEBUG_BIND} + +@deftypefn {GIMPLE function} gimple gimple_build_debug_bind (tree var, tree value, gimple stmt) +Build a @code{GIMPLE_DEBUG} statement with @code{GIMPLE_DEBUG_BIND} of +@code{subcode}. The effect of this statement is to tell debug +information generation machinery that the value of user variable +@code{var} is given by @code{value} at that point, and to remain with +that value until @code{var} runs out of scope, a +dynamically-subsequent debug bind statement overrides the binding, or +conflicting values reach a control flow merge point. Even if +components of the @code{value} expression change afterwards, the +variable is supposed to retain the same value, though not necessarily +the same location. + +It is expected that @code{var} be most often a tree for automatic user +variables (@code{VAR_DECL} or @code{PARM_DECL}) that satisfy the +requirements for gimple registers, but it may also be a tree for a +scalarized component of a user variable (@code{ARRAY_REF}, +@code{COMPONENT_REF}), or a debug temporary (@code{DEBUG_EXPR_DECL}). + +As for @code{value}, it can be an arbitrary tree expression, but it is +recommended that it be in a suitable form for a gimple assignment +@code{RHS}. It is not expected that user variables that could appear +as @code{var} ever appear in @code{value}, because in the latter we'd +have their @code{SSA_NAME}s instead, but even if they were not in SSA +form, user variables appearing in @code{value} are to be regarded as +part of the executable code space, whereas those in @code{var} are to +be regarded as part of the source code space. There is no way to +refer to the value bound to a user variable within a @code{value} +expression. + +If @code{value} is @code{GIMPLE_DEBUG_BIND_NOVALUE}, debug information +generation machinery is informed that the variable @code{var} is +unbound, i.e., that its value is indeterminate, which sometimes means +it is really unavailable, and other times that the compiler could not +keep track of it. + +Block and location information for the newly-created stmt are +taken from @code{stmt}, if given. +@end deftypefn + +@deftypefn {GIMPLE function} tree gimple_debug_bind_get_var (gimple stmt) +Return the user variable @var{var} that is bound at @code{stmt}. +@end deftypefn + +@deftypefn {GIMPLE function} tree gimple_debug_bind_get_value (gimple stmt) +Return the value expression that is bound to a user variable at +@code{stmt}. +@end deftypefn + +@deftypefn {GIMPLE function} tree *gimple_debug_bind_get_value_ptr (gimple stmt) +Return a pointer to the value expression that is bound to a user +variable at @code{stmt}. +@end deftypefn + +@deftypefn {GIMPLE function} void gimple_debug_bind_set_var (gimple stmt, tree var) +Modify the user variable bound at @code{stmt} to @var{var}. +@end deftypefn + +@deftypefn {GIMPLE function} void gimple_debug_bind_set_value (gimple stmt, tree var) +Modify the value bound to the user variable bound at @code{stmt} to +@var{value}. +@end deftypefn + +@deftypefn {GIMPLE function} void gimple_debug_bind_reset_value (gimple stmt) +Modify the value bound to the user variable bound at @code{stmt} so +that the variable becomes unbound. +@end deftypefn + +@deftypefn {GIMPLE function} bool gimple_debug_bind_has_value_p (gimple stmt) +Return @code{TRUE} if @code{stmt} binds a user variable to a value, +and @code{FALSE} if it unbinds the variable. +@end deftypefn + @node @code{GIMPLE_EH_FILTER} @subsection @code{GIMPLE_EH_FILTER} @cindex @code{GIMPLE_EH_FILTER} |