In the RTL representation, the macros @code{BB_HEAD} and @code{BB_END}
may be used to get the head and end @code{rtx} of a basic block. No
abstract iterators are defined for traversing the insn chain, but you
-can just use @code{NEXT_INSN} and @code{PREV_INSN} instead. See
-@xref{Insns}.
+can just use @code{NEXT_INSN} and @code{PREV_INSN} instead. @xref{Insns}.
@findex purge_dead_edges
Usually a code manipulating pass simplifies the instruction stream and
iterator on an edge, and @code{bsi_commit_edge_inserts} which flushes
the instruction to actual instruction stream.
-While debugging the optimization pass, an @code{verify_flow_info}
+While debugging the optimization pass, a @code{verify_flow_info}
function may be useful to find bugs in the control flow graph updating
code.
used, for instance, during register allocation, as the pseudo
registers only need to be assigned to a unique hard register or to a
stack slot if they are live. The hard registers and stack slots may
-be freely reused for other values when a register is dead.
+be freely reused for other values when a register is dead.
Liveness information is available in the back end starting with
@code{pass_df_initialize} and ending with @code{pass_df_finish}. Three
to determine at any point @code{P} in the function if the register may be
used on some path from @code{P} to the end of the function. With
@code{UR}, it is possible to determine if there is a path from the
-beginning of the function to @code{P} that defines the variable.
+beginning of the function to @code{P} that defines the variable.
@code{LIVE} is the intersection of the @code{LR} and @code{UR} and a
variable is live at @code{P} if there is both an assignment that reaches
-it from the beginning of the function and a uses that can be reached on
+it from the beginning of the function and a use that can be reached on
some path from @code{P} to the end of the function.
In general @code{LIVE} is the most useful of the three. The macros
The macros take a basic block number and return a bitmap that is indexed
by the register number. This information is only guaranteed to be up to
date after calls are made to @code{df_analyze}. See the file
-@code{df-core.c} for details on using the dataflow.
+@code{df-core.c} for details on using the dataflow.
@findex REG_DEAD, REG_UNUSED
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