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@@ -37,8 +37,6 @@ Changes to Changelog files are dropped.
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gas/config/tc-xtensa.c | 558 +++++++++++++++++++++++++++++++++-
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gas/config/tc-xtensa.h | 5 +
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- gas/doc/as.texinfo | 1 +
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- gas/doc/c-xtensa.texi | 92 ++++++
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gas/frags.c | 15 +
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gas/frags.h | 3 +
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gas/testsuite/gas/xtensa/all.exp | 1 +
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@@ -727,135 +725,6 @@ index 0bf1240..4672bc6 100644
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RELAX_NONE
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};
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-diff --git a/gas/doc/as.texinfo b/gas/doc/as.texinfo
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-index 5c8b000..dc97175 100644
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---- a/gas/doc/as.texinfo
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-+++ b/gas/doc/as.texinfo
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-@@ -543,6 +543,7 @@ gcc(1), ld(1), and the Info entries for @file{binutils} and @file{ld}.
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- [@b{--[no-]target-align}] [@b{--[no-]longcalls}]
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- [@b{--[no-]transform}]
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- [@b{--rename-section} @var{oldname}=@var{newname}]
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-+ [@b{--[no-]trampolines}]
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- @end ifset
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-
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- @ifset Z80
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-diff --git a/gas/doc/c-xtensa.texi b/gas/doc/c-xtensa.texi
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-index 406e635..e763e36 100644
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---- a/gas/doc/c-xtensa.texi
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-+++ b/gas/doc/c-xtensa.texi
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-@@ -91,6 +91,16 @@ instruction operands to be errors.
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- @kindex --rename-section
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- Rename the @var{oldname} section to @var{newname}. This option can be used
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- multiple times to rename multiple sections.
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-+
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-+@item --trampolines | --no-trampolines
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-+@kindex --trampolines
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-+@kindex --no-trampolines
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-+Enable or disable transformation of jump instructions to allow jumps
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-+across a greater range of addresses. @xref{Xtensa Jump Relaxation,
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-+,Jump Trampolines}. This option should be used when jump targets can
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-+potentially be out of range. In the absence of such jumps this option
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-+does not affect code size or performance. The default is
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-+@samp{--trampolines}.
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- @end table
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-
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- @c man end
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-@@ -311,6 +321,7 @@ fields.
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- @menu
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- * Xtensa Branch Relaxation:: Relaxation of Branches.
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- * Xtensa Call Relaxation:: Relaxation of Function Calls.
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-+* Xtensa Jump Relaxation:: Relaxation of Jumps.
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- * Xtensa Immediate Relaxation:: Relaxation of other Immediate Fields.
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- @end menu
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-
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-@@ -398,6 +409,87 @@ and some of the calls are out of range, function call relaxation can be
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- enabled using the @samp{--longcalls} command-line option or the
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- @code{longcalls} directive (@pxref{Longcalls Directive, ,longcalls}).
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-
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-+@node Xtensa Jump Relaxation
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-+@subsection Jump Relaxation
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-+@cindex relaxation of jump instructions
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-+@cindex jump instructions, relaxation
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-+
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-+Jump instruction may require relaxation because the Xtensa jump instruction
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-+(@code{J}) provide a PC-relative offset of only 128 Kbytes in either
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-+direction. One option is to use jump long (@code{J.L}) instruction, which
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-+depending on jump distance may be assembled as jump (@code{J}) or indirect
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-+jump (@code{JX}). However it needs a free register. When there's no spare
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-+register it is possible to plant intermediate jump sites (trampolines)
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-+between the jump instruction and its target. These sites may be located in
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-+areas unreachable by normal code execution flow, in that case they only
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-+contain intermediate jumps, or they may be inserted in the middle of code
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-+block, in which case there's an additional jump from the beginning of the
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-+trampoline to the instruction past its end. So, for example:
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-+
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-+@smallexample
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-+@group
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-+ j 1f
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-+ ...
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-+ retw
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-+ ...
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-+ mov a10, a2
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-+ call8 func
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-+ ...
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-+1:
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-+ ...
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-+@end group
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-+@end smallexample
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-+
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-+might be relaxed to:
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-+
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-+@smallexample
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-+@group
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-+ j .L0_TR_1
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-+ ...
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-+ retw
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-+.L0_TR_1:
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-+ j 1f
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-+ ...
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-+ mov a10, a2
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-+ call8 func
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-+ ...
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-+1:
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-+ ...
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-+@end group
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-+@end smallexample
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-+
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-+or to:
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-+
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-+@smallexample
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-+@group
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-+ j .L0_TR_1
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-+ ...
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-+ retw
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-+ ...
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-+ mov a10, a2
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-+ j .L0_TR_0
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-+.L0_TR_1:
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-+ j 1f
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-+.L0_TR_0:
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-+ call8 func
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-+ ...
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-+1:
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-+ ...
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-+@end group
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-+@end smallexample
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-+
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-+The Xtensa assempler uses trampolines with jump around only when it cannot
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-+find suitable unreachable trampoline. There may be multiple trampolines
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-+between the jump instruction and its target.
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-+
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-+This relaxation does not apply to jumps to undefined symbols, assuming they
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-+will reach their targets once resolved.
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-+
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-+Jump relaxation is enabled by default because it does not affect code size
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-+or performance while the code itself is small. This relaxation may be
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-+disabled completely with @samp{--no-trampolines} or @samp{--no-transform}
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-+command-line options (@pxref{Xtensa Options, ,Command Line Options}).
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-+
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- @node Xtensa Immediate Relaxation
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- @subsection Other Immediate Field Relaxation
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- @cindex immediate fields, relaxation
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diff --git a/gas/frags.c b/gas/frags.c
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index 5f68480..e14099d 100644
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--- a/gas/frags.c
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Max Filippov