+@cindex @samp{-malign-branch-boundary=} option, i386
+@cindex @samp{-malign-branch-boundary=} option, x86-64
+@item -malign-branch-boundary=@var{NUM}
+This option controls how the assembler should align branches with segment
+prefixes or NOP. @var{NUM} must be a power of 2. It should be 0 or
+no less than 16. Branches will be aligned within @var{NUM} byte
+boundary. @option{-malign-branch-boundary=0}, which is the default,
+doesn't align branches.
+
+@cindex @samp{-malign-branch=} option, i386
+@cindex @samp{-malign-branch=} option, x86-64
+@item -malign-branch=@var{TYPE}[+@var{TYPE}...]
+This option specifies types of branches to align. @var{TYPE} is
+combination of @samp{jcc}, which aligns conditional jumps,
+@samp{fused}, which aligns fused conditional jumps, @samp{jmp},
+which aligns unconditional jumps, @samp{call} which aligns calls,
+@samp{ret}, which aligns rets, @samp{indirect}, which aligns indirect
+jumps and calls. The default is @option{-malign-branch=jcc+fused+jmp}.
+
+@cindex @samp{-malign-branch-prefix-size=} option, i386
+@cindex @samp{-malign-branch-prefix-size=} option, x86-64
+@item -malign-branch-prefix-size=@var{NUM}
+This option specifies the maximum number of prefixes on an instruction
+to align branches. @var{NUM} should be between 0 and 5. The default
+@var{NUM} is 5.
+
+@cindex @samp{-mbranches-within-32B-boundaries} option, i386
+@cindex @samp{-mbranches-within-32B-boundaries} option, x86-64
+@item -mbranches-within-32B-boundaries
+This option aligns conditional jumps, fused conditional jumps and
+unconditional jumps within 32 byte boundary with up to 5 segment prefixes
+on an instruction. It is equivalent to
+@option{-malign-branch-boundary=32}
+@option{-malign-branch=jcc+fused+jmp}
+@option{-malign-branch-prefix-size=5}.
+The default doesn't align branches.
+
+@cindex @samp{-mlfence-after-load=} option, i386
+@cindex @samp{-mlfence-after-load=} option, x86-64
+@item -mlfence-after-load=@var{no}
+@itemx -mlfence-after-load=@var{yes}
+These options control whether the assembler should generate lfence
+after load instructions. @option{-mlfence-after-load=@var{yes}} will
+generate lfence. @option{-mlfence-after-load=@var{no}} will not generate
+lfence, which is the default.
+
+@cindex @samp{-mlfence-before-indirect-branch=} option, i386
+@cindex @samp{-mlfence-before-indirect-branch=} option, x86-64
+@item -mlfence-before-indirect-branch=@var{none}
+@item -mlfence-before-indirect-branch=@var{all}
+@item -mlfence-before-indirect-branch=@var{register}
+@itemx -mlfence-before-indirect-branch=@var{memory}
+These options control whether the assembler should generate lfence
+before indirect near branch instructions.
+@option{-mlfence-before-indirect-branch=@var{all}} will generate lfence
+before indirect near branch via register and issue a warning before
+indirect near branch via memory.
+It also implicitly sets @option{-mlfence-before-ret=@var{shl}} when
+there's no explict @option{-mlfence-before-ret=}.
+@option{-mlfence-before-indirect-branch=@var{register}} will generate
+lfence before indirect near branch via register.
+@option{-mlfence-before-indirect-branch=@var{memory}} will issue a
+warning before indirect near branch via memory.
+@option{-mlfence-before-indirect-branch=@var{none}} will not generate
+lfence nor issue warning, which is the default. Note that lfence won't
+be generated before indirect near branch via register with
+@option{-mlfence-after-load=@var{yes}} since lfence will be generated
+after loading branch target register.
+
+@cindex @samp{-mlfence-before-ret=} option, i386
+@cindex @samp{-mlfence-before-ret=} option, x86-64
+@item -mlfence-before-ret=@var{none}
+@item -mlfence-before-ret=@var{shl}
+@item -mlfence-before-ret=@var{or}
+@item -mlfence-before-ret=@var{yes}
+@itemx -mlfence-before-ret=@var{not}
+These options control whether the assembler should generate lfence
+before ret. @option{-mlfence-before-ret=@var{or}} will generate
+generate or instruction with lfence.
+@option{-mlfence-before-ret=@var{shl/yes}} will generate shl instruction
+with lfence. @option{-mlfence-before-ret=@var{not}} will generate not
+instruction with lfence. @option{-mlfence-before-ret=@var{none}} will not
+generate lfence, which is the default.
+
+@cindex @samp{-mx86-used-note=} option, i386
+@cindex @samp{-mx86-used-note=} option, x86-64
+@item -mx86-used-note=@var{no}
+@itemx -mx86-used-note=@var{yes}
+These options control whether the assembler should generate
+GNU_PROPERTY_X86_ISA_1_USED and GNU_PROPERTY_X86_FEATURE_2_USED
+GNU property notes. The default can be controlled by the
+@option{--enable-x86-used-note} configure option.
+
projects / deliverable / binutils-gdb.git / blobdiff