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Completed first draft of TLS ABI changes for PC-relative. Under review.

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master
Bill Schmidt 5 years ago
parent 4887a0b440
commit bed1094157
1 changed files with 60 additions and 342 deletions
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specification/ch_3.xml
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@ -5810,7 +5810,7 @@ extern void *__tls_get_addr (tls_index *ti);</programlisting>
</row>
<row>
<entry morerows="1">
<para>bl __tls_get_addr(x@tlsgd)</para>
<para>bl __tls_get_addr@notoc(x@tlsgd)</para>
</entry>
<entry>
<para>R_PPC64_TLSGD</para>
@ -6125,7 +6125,7 @@ static __thread unsigned int x3;
</row>
<row>
<entry morerows="1">
<para>bl __tls_get_addr(x1@tlsld)</para>
<para>bl __tls_get_addr@notoc(x1@tlsld)</para>
</entry>
<entry>
<para>R_PPC64_TLSLD</para>
@ -8319,21 +8319,10 @@ nop</programlisting>
<tbody>
<row>
<entry>
<para>addis r3, r2, x@got@tlsgd@ha</para>
</entry>
<entry>
<para>R_PPC64_GOT_TLSGD16_HA</para>
</entry>
<entry>
<para>x</para>
</entry>
</row>
<row>
<entry>
<para>addi r3, r3, x@got@tlsgd@l</para>
<para>pla r3, x@got@tlsgd@pcrel</para>
</entry>
<entry>
<para>R_PPC64_GOT_TLSGD16_LO</para>
<para>R_PPC64_GOT_TLSGD34</para>
</entry>
<entry>
<para>x</para>
@ -8341,7 +8330,7 @@ nop</programlisting>
</row>
<row>
<entry morerows="1">
<para>bl __tls_get_addr(x@tlsgd)</para>
<para>bl __tls_get_addr@notoc(x@tlsgd)</para>
</entry>
<entry>
<para>R_PPC64_TLSGD</para>
@ -8352,23 +8341,12 @@ nop</programlisting>
</row>
<row>
<entry>
<para>R_PPC64_REL24</para>
<para>R_PPC64_REL24_NOTOC</para>
</entry>
<entry>
<para>__tls_get_addr</para>
</entry>
</row>
<row>
<entry>
<para>nop</para>
</entry>
<entry>
<para> </para>
</entry>
<entry>
<para> </para>
</entry>
</row>
</tbody>
</tgroup>
</table>
@ -8457,37 +8435,15 @@ nop</programlisting>
<tbody>
<row>
<entry>
<para>addis r3, r2, x@got@tprel@ha</para>
</entry>
<entry>
<para>R_PPC64_GOT_TPREL16_HA</para>
<para>pld r3, x@got@tprel@pcrel</para>
</entry>
<entry>
<para>x</para>
</entry>
</row>
<row>
<entry>
<para>ld r3, x@got@tprel@l(r3)</para>
</entry>
<entry>
<para>R_PPC64_GOT_TPREL16_LO_DS</para>
<para>R_PPC64_GOT_TPREL34</para>
</entry>
<entry>
<para>x</para>
</entry>
</row>
<row>
<entry>
<para>nop</para>
</entry>
<entry>
<para> </para>
</entry>
<entry>
<para> </para>
</entry>
</row>
<row>
<entry>
<para>add r3, r3, r13</para>
@ -8576,21 +8532,10 @@ nop</programlisting>
<tbody>
<row>
<entry>
<para>addis r3, r2, x@got@tlsgd@ha</para>
</entry>
<entry>
<para>R_PPC64_GOT_TLSGD16_HA</para>
</entry>
<entry>
<para>x</para>
</entry>
</row>
<row>
<entry>
<para>addi r3, r3, x@got@tlsgd@l</para>
<para>pla r3, x@got@tlsgd@pcrel</para>
</entry>
<entry>
<para>R_PPC64_GOT_TLSGD16_LO</para>
<para>R_PPC64_GOT_TLSGD34</para>
</entry>
<entry>
<para>x</para>
@ -8598,7 +8543,7 @@ nop</programlisting>
</row>
<row>
<entry morerows="1">
<para>bl __tls_get_addr(x@tlsgd)</para>
<para>bl __tls_get_addr@notoc(x@tlsgd)</para>
</entry>
<entry>
<para>R_PPC64_TLSGD</para>
@ -8609,23 +8554,12 @@ nop</programlisting>
</row>
<row>
<entry>
<para>R_PPC64_REL24</para>
<para>R_PPC64_REL24_NOTOC</para>
</entry>
<entry>
<para>__tls_get_addr</para>
</entry>
</row>
<row>
<entry>
<para>nop</para>
</entry>
<entry>
<para> </para>
</entry>
<entry>
<para> </para>
</entry>
</row>
</tbody>
</tgroup>
</table>
@ -8683,18 +8617,9 @@ nop</programlisting>
</table>
<para>The preceding code and global offset table entries are replaced by
the following code, which makes no reference to GOT entries. The GOT
entries in
<xref linkend="dbdoclet.50655241_16273" /> can be removed from the GOT by
the linker when performing this code transformation.<footnote xml:id="pgfId-1134055p">
<para>To further optimize the code in
<xref linkend="dbdoclet.50655241_16273" />, a linker may reschedule the
sequence to exploit fusion by generating a sequence that may be fused
by Power processors:</para>
<programlisting>nop
addis r3, r13, x@tprel@ha
addi r3, r3, x@tprel@l
nop</programlisting>
</footnote></para>
entries in <xref linkend="dbdoclet.50655241_16273p" /> can be
removed from the GOT by the linker when performing this code
transformation.</para>
<table frame="all" pgwide="1">
<title>General-Dynamic-to-Local-Exec Replacement Initial
Relocations (PC-Relative)</title>
@ -8724,21 +8649,10 @@ nop</programlisting>
<tbody>
<row>
<entry>
<para>nop</para>
</entry>
<entry>
<para> </para>
</entry>
<entry>
<para> </para>
</entry>
</row>
<row>
<entry>
<para>addis r3, r13, x@tprel@ha</para>
<para>paddi r3, r13, x@tprel</para>
</entry>
<entry>
<para>R_PPC64_TPREL16_HA</para>
<para>R_PPC64_TPREL34</para>
</entry>
<entry>
<para>x</para>
@ -8755,17 +8669,6 @@ nop</programlisting>
<para> </para>
</entry>
</row>
<row>
<entry>
<para>addi r3, r3, x@tprel@l</para>
</entry>
<entry>
<para>R_PPC64_TPREL16_LO</para>
</entry>
<entry>
<para>x</para>
</entry>
</row>
</tbody>
</tgroup>
</table>
@ -8804,21 +8707,10 @@ nop</programlisting>
<tbody>
<row>
<entry>
<para>addis r3, r2, x1@got@tlsld@ha</para>
</entry>
<entry>
<para>R_PPC64_GOT_TLSLD16_HA</para>
</entry>
<entry>
<para>x1</para>
</entry>
</row>
<row>
<entry>
<para>addi r3, r3, x1@got@tlsld@l</para>
<para>pla r3, x1@got@tlsld@pcrel</para>
</entry>
<entry>
<para>R_PPC64_GOT_TLSLD16_LO</para>
<para>R_PPC64_GOT_TLSLD34</para>
</entry>
<entry>
<para>x1</para>
@ -8826,7 +8718,7 @@ nop</programlisting>
</row>
<row>
<entry>
<para>bl __tls_get_addr(x1@tlsld)</para>
<para>bl __tls_get_addr@notoc(x1@tlsld)</para>
</entry>
<entry>
<para>R_PPC64_TLSLD</para>
@ -8840,45 +8732,12 @@ nop</programlisting>
<para> </para>
</entry>
<entry>
<para>R_PPC64_REL24</para>
<para>R_PPC64_REL24_NOTOC</para>
</entry>
<entry>
<para>__tls_get_addr</para>
</entry>
</row>
<row>
<entry>
<para>nop</para>
</entry>
<entry>
<para> </para>
</entry>
<entry>
<para> </para>
</entry>
</row>
<row>
<entry>
<para>...</para>
</entry>
<entry>
<para> </para>
</entry>
<entry>
<para> </para>
</entry>
</row>
<row>
<entry>
<para>addi r9, r3, x1@dtprel</para>
</entry>
<entry>
<para>R_PPC64_DTPREL16</para>
</entry>
<entry>
<para>x1</para>
</entry>
</row>
<row>
<entry>
<para>...</para>
@ -8892,21 +8751,10 @@ nop</programlisting>
</row>
<row>
<entry>
<para>addis r9, r3, x2@dtprel@ha</para>
</entry>
<entry>
<para>R_PPC64_DTPREL16_HA</para>
</entry>
<entry>
<para>x2</para>
</entry>
</row>
<row>
<entry>
<para>addi r9, r9, x2@dtprel@l</para>
<para>paddi r9, r3, x2@dtprel</para>
</entry>
<entry>
<para>R_PPC64_DTPREL16_LO</para>
<para>R_PPC64_DTPREL34</para>
</entry>
<entry>
<para>x2</para>
@ -8925,21 +8773,10 @@ nop</programlisting>
</row>
<row>
<entry>
<para>addis r9, r2, x3@got@dtprel@ha</para>
</entry>
<entry>
<para>R_PPC64_GOT_DTPREL16_HA</para>
</entry>
<entry>
<para>x3</para>
</entry>
</row>
<row>
<entry>
<para>ld r9, x3@got@dtprel@l(r9)</para>
<para>pld r9, x3@got@dtprel@pcrel</para>
</entry>
<entry>
<para>R_PPC64_GOT_DTPREL16_LO_DS</para>
<para>R_PPC64_GOT_DTPREL34</para>
</entry>
<entry>
<para>x3</para>
@ -9064,7 +8901,7 @@ nop</programlisting>
<tbody>
<row>
<entry>
<para>nop</para>
<para>paddi r3, r13, 0x1000</para>
</entry>
<entry>
<para></para>
@ -9073,17 +8910,6 @@ nop</programlisting>
<para></para>
</entry>
</row>
<row>
<entry>
<para>addis r3, r13, L@tprel@ha</para>
</entry>
<entry>
<para>R_PPC64_TPREL16_HA</para>
</entry>
<entry>
<para>link editor generated local symbol</para>
</entry>
</row>
<row>
<entry>
<para>nop</para>
@ -9095,43 +8921,6 @@ nop</programlisting>
<para> </para>
</entry>
</row>
<row>
<entry>
<para>addi r3, r3, L@tprel@l</para>
</entry>
<entry>
<para>R_PPC64_TPREL16_LO</para>
</entry>
<entry>
<para>link editor generated local symbol<footnote>
<para>The linker may prefer to schedule the addis and addi
to be adjacent to take advantage of fusion as a
microarchitecture optimization opportunity.</para></footnote>
</para>
</entry>
</row>
<row>
<entry>
<para>..</para>
</entry>
<entry>
<para> </para>
</entry>
<entry>
<para> </para>
</entry>
</row>
<row>
<entry>
<para>addi r9, r3, x1@dtprel</para>
</entry>
<entry>
<para>R_PPC64_DTPREL16</para>
</entry>
<entry>
<para>x1</para>
</entry>
</row>
<row>
<entry>
<para>..</para>
@ -9145,21 +8934,10 @@ nop</programlisting>
</row>
<row>
<entry>
<para>addis r9, r3, x2@dtprel@ha</para>
</entry>
<entry>
<para>R_PPC64_DTPREL16_HA</para>
</entry>
<entry>
<para>x2</para>
</entry>
</row>
<row>
<entry>
<para>addi r9, r9, x2@dtprel@l</para>
<para>paddi r9, r3, x2@dtprel</para>
</entry>
<entry>
<para>R_PPC64_DTPREL16_LO</para>
<para>R_PPC64_DTPREL34</para>
</entry>
<entry>
<para>x2</para>
@ -9167,7 +8945,7 @@ nop</programlisting>
</row>
<row>
<entry>
<para>...</para>
<para>..</para>
</entry>
<entry>
<para> </para>
@ -9178,21 +8956,10 @@ nop</programlisting>
</row>
<row>
<entry>
<para>addis r9, r2, x3@got@dtprel@ha</para>
</entry>
<entry>
<para>R_PPC64_GOT_DTPREL16_HA</para>
</entry>
<entry>
<para>x3</para>
</entry>
</row>
<row>
<entry>
<para>ld r9, x3@got@dtprel@l(r9)</para>
<para>pld r9, x3@got@dtprel@pcrel</para>
</entry>
<entry>
<para>R_PPC64_GOT_DTPREL16_LO_DS</para>
<para>R_PPC64_GOT_DTPREL34</para>
</entry>
<entry>
<para>x3</para>
@ -9214,7 +8981,7 @@ nop</programlisting>
</table>
<para>The GOT[n] and GOT[n+1] entries can be removed by the linker after
the code transformation as shown in
<xref linkend="dbdoclet.50655241_90771" />.</para>
<xref linkend="dbdoclet.50655241_90771p" />.</para>
<table frame="all" pgwide="1" xml:id="dbdoclet.50655241_90771p">
<title>Local-Dynamic-to-Local-Exec Replacement GOT Entry
Relocations (PC-Relative)</title>
@ -9256,14 +9023,9 @@ nop</programlisting>
</tbody>
</tgroup>
</table>
<para>The local symbol generated by the link editor points to the start
of the thread storage block plus 0x7000 bytes. In practice, a section
symbol with a suitable offset will be used.</para>
</section>
<section xml:id="dbdoclet.ie-le-pcrel" revisionflag="added">
<title>Initial Exec to Local Exec (PC-Relative)</title>
<para>This transformation is only performed by the linker when the symbol
is within 2 GB + 28 KB of the thread pointer.</para>
<table frame="all" pgwide="1">
<title>Initial-Exec-to-Local-Exec Initial Relocations</title>
<tgroup cols="3">
@ -9292,21 +9054,10 @@ nop</programlisting>
<tbody>
<row>
<entry>
<para>addis r9, r2, x@got@tprel@ha</para>
</entry>
<entry>
<para>R_PPC64_GOT_TPREL16_HA</para>
</entry>
<entry>
<para>x</para>
</entry>
</row>
<row>
<entry>
<para>ld r9, x@got@tprel@l(r9)</para>
<para>pld r9, x@got@tprel@pcrel</para>
</entry>
<entry>
<para>R_PPC64_GOT_TPREL16_LO_DS</para>
<para>R_PPC64_GOT_TPREL34</para>
</entry>
<entry>
<para>x</para>
@ -9314,10 +9065,10 @@ nop</programlisting>
</row>
<row>
<entry>
<para>add r9, r9, x@tls</para>
<para>add r9, r9, x@tls@pcrel</para>
</entry>
<entry>
<para>R_PPC64_TLS</para>
<para>R_PPC64_TLS with one-byte displacement</para>
</entry>
<entry>
<para>x</para>
@ -9368,7 +9119,8 @@ nop</programlisting>
</tgroup>
</table>
<para>The preceding code and global offset table entries are replaced by
the following code and global offset table entries.</para>
the following code. The global offset entry GOT[n] can be
eliminated by the linker.</para>
<table frame="all" pgwide="1">
<title>Initial-Exec-to-Local-Exec Replacement Initial
Relocations (PC-Relative)</title>
@ -9390,21 +9142,10 @@ nop</programlisting>
</row>
<row>
<entry>
<para>nop</para>
</entry>
<entry>
<para> </para>
<para>paddi r9, r9, x@tprel@l</para>
</entry>
<entry>
<para> </para>
</entry>
</row>
<row>
<entry>
<para>addis r9, r13, x@tprel@ha</para>
</entry>
<entry>
<para>R_PPC64_TPREL16_HA</para>
<para>R_PPC64_TPREL34</para>
</entry>
<entry>
<para>x</para>
@ -9412,22 +9153,20 @@ nop</programlisting>
</row>
<row>
<entry>
<para>addi r9, r9, x@tprel@l</para>
<para>nop</para>
</entry>
<entry>
<para>R_PPC64_TPREL16_LO</para>
<para> </para>
</entry>
<entry>
<para>x</para>
<para> </para>
</entry>
</row>
</tbody>
</tgroup>
</table>
<para>Other sizes and types of thread-local variables may use any of the
X-form indexed load or store instructions.</para>
<para>
<xref linkend="dbdoclet.50655241_81882" /> shows how to access the
<xref linkend="dbdoclet.50655241_81882p" /> shows how to access the
contents of a variable using the X-form indexed load and store
instructions.</para>
<table frame="all" pgwide="1" xml:id="dbdoclet.50655241_81882p">
@ -9459,21 +9198,10 @@ nop</programlisting>
<tbody>
<row>
<entry>
<para>addis r9, r2, x@got@tprel@ha</para>
</entry>
<entry>
<para>R_PPC64_GOT_TPREL16_HA</para>
</entry>
<entry>
<para>x</para>
</entry>
</row>
<row>
<entry>
<para>ld r9, x@got@tprel@l(r9)</para>
<para>pld r9, x@got@tprel@pcrel</para>
</entry>
<entry>
<para>R_PPC64_GOT_TPREL16_LO_DS</para>
<para>R_PPC64_GOT_TPREL34</para>
</entry>
<entry>
<para>x</para>
@ -9481,7 +9209,7 @@ nop</programlisting>
</row>
<row>
<entry>
<para>lbzx r10, r9, x@tls</para>
<para>lbzx r10, r9, x@tls@pcrel</para>
</entry>
<entry>
<para>R_PPC64_TLS</para>
@ -9503,7 +9231,7 @@ nop</programlisting>
</row>
<row>
<entry>
<para>stbx r10, r9, x@tls</para>
<para>stbx r10, r9, x@tls@pcrel</para>
</entry>
<entry>
<para>R_PPC64_TLS</para>
@ -9557,7 +9285,8 @@ nop</programlisting>
</tgroup>
</table>
<para>The preceding code and global offset table entries are replaced by
the following code and global offset table entries.</para>
the following code. The global offset table entry GOT[n] can be
removed by the linker.</para>
<table frame="all" pgwide="1">
<title>Initial-Exec-to-Local-Exec X-form Replacement Initial
Relocations (PC-Relative)</title>
@ -9587,21 +9316,10 @@ nop</programlisting>
<tbody>
<row>
<entry>
<para>nop</para>
</entry>
<entry>
<para> </para>
</entry>
<entry>
<para> </para>
</entry>
</row>
<row>
<entry>
<para>addis r9, r13, x@tprel@ha</para>
<para>paddi r9, r13, x@tprel</para>
</entry>
<entry>
<para>R_PPC64_TPREL16_HA</para>
<para>R_PPC64_TPREL34</para>
</entry>
<entry>
<para>x</para>
@ -9609,13 +9327,13 @@ nop</programlisting>
</row>
<row>
<entry>
<para>lbz r10, x@tprel@l(r9)</para>
<para>lbz r10, 0(r9)</para>
</entry>
<entry>
<para>R_PPC64_TPREL16_LO</para>
<para></para>
</entry>
<entry>
<para>x</para>
<para></para>
</entry>
</row>
<row>
@ -9631,13 +9349,13 @@ nop</programlisting>
</row>
<row>
<entry>
<para>stb r10, x@tprel@l(r9)</para>
<para>stb r10, 0(r9)</para>
</entry>
<entry>
<para>R_PPC64_TPREL16_LO</para>
<para></para>
</entry>
<entry>
<para>x</para>
<para></para>
</entry>
</row>
</tbody>

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