diff options
Diffstat (limited to 'gcc/doc/md.texi')
| -rw-r--r-- | gcc/doc/md.texi | 12 |
1 files changed, 5 insertions, 7 deletions
diff --git a/gcc/doc/md.texi b/gcc/doc/md.texi index a78233c8eaa..b966c27a880 100644 --- a/gcc/doc/md.texi +++ b/gcc/doc/md.texi @@ -552,7 +552,7 @@ As a special case, a template consisting of the single character @code{#} instructs the compiler to first split the insn, and then output the resulting instructions separately. This helps eliminate redundancy in the output templates. If you have a @code{define_insn} that needs to emit -multiple assembler instructions, and there is an matching @code{define_split} +multiple assembler instructions, and there is a matching @code{define_split} already defined, then you can simply use @code{#} as the output template instead of writing an output template that emits the multiple assembler instructions. @@ -3323,7 +3323,7 @@ memory address of this type. If @samp{Q} is defined with @code{define_memory_constraint}, a @samp{Q} constraint can handle any memory operand, because @code{reload} knows it can simply copy the memory address into a base register if required. This is analogous to -the way a @samp{o} constraint can handle any memory operand. +the way an @samp{o} constraint can handle any memory operand. The syntax and semantics are otherwise identical to @code{define_constraint}. @@ -4729,7 +4729,7 @@ A label that precedes the table itself. A label to jump to if the index has a value outside the bounds. @end enumerate -The table is a @code{addr_vec} or @code{addr_diff_vec} inside of a +The table is an @code{addr_vec} or @code{addr_diff_vec} inside of a @code{jump_insn}. The number of elements in the table is one plus the difference between the upper bound and the lower bound. @@ -4949,7 +4949,7 @@ the first three are normally used by the generic mechanism. @cindex @code{builtin_setjmp_receiver} instruction pattern @item @samp{builtin_setjmp_receiver} -This pattern, if defined, contains code needed at the site of an +This pattern, if defined, contains code needed at the site of a built-in setjmp that isn't needed at the site of a nonlocal goto. You will not normally need to define this pattern. A typical reason why you might need this pattern is if some value, such as a pointer to a global @@ -5115,8 +5115,6 @@ These patterns emit code for an atomic operation on memory. Operand 0 is the memory on which the atomic operation is performed. Operand 1 is the second operand to the binary operator. -The ``nand'' operation is @code{~op0 & op1}. - This pattern must issue any memory barrier instructions such that all memory operations before the atomic operation occur before the atomic operation and all memory operations after the atomic operation occur @@ -6116,7 +6114,7 @@ more assistance is needed. Splitter is required to create only unconditional jumps, or simple conditional jump instructions. Additionally it must attach a @code{REG_BR_PROB} note to each conditional jump. A global variable @code{split_branch_probability} holds the probability of the original branch in case -it was an simple conditional jump, @minus{}1 otherwise. To simplify +it was a simple conditional jump, @minus{}1 otherwise. To simplify recomputing of edge frequencies, the new sequence is required to have only forward jumps to the newly created labels. |