Linker and Libraries Guide

SPARC: Thread-Local Storage Relocation Types

The TLS relocations that are listed in the following table are defined for SPARC. Descriptions in the table use the following notation.

@dtlndx(x): Allocates two contiguous entries in the GOT to hold a TLS_index structure. This information is passed to __tls_get_addr(). The instruction referencing this entry is bound to the address of the first of the two GOT entries.
@tmndx(x): Allocates two contiguous entries in the GOT to hold a TLS_index structure. This information is passed to __tls_get_addr(). The ti_tlsoffset field of this structure is set to 0, and the ti_moduleid is filled in at runtime. The call to __tls_get_addr() returns the starting offset of the dynamic TLS block.
@dtpoff(x): Calculates the tlsoffset relative to the TLS block.
@tpoff(x): Calculates the negative tlsoffset relative to the static TLS block. This value is added to the thread-pointer to calculate the TLS address.
@dtpmod(x): Calculates the object identifier of the object containing a TLS symbol.

Table 8–7 SPARC: Thread-Local Storage Relocation Types


Name	Value	Field	Calculation
`R_SPARC_TLS_GD_HI22`	`56`	`T-simm22`	`@dtlndx(S + A) >> 10`
`R_SPARC_TLS_GD_LO10`	`57`	`T-simm13`	`@dtlndx(S + A) & 0x3ff`
`R_SPARC_TLS_GD_ADD`	`58`	None	Refer to the explanation following this table.
`R_SPARC_TLS_GD_CALL`	`59`	`V-disp30`	Refer to the explanation following this table.
`R_SPARC_TLS_LDM_HI22`	`60`	`T-simm22`	`@tmndx(S + A) >> 10`
`R_SPARC_TLS_LDM_LO10`	`61`	`T-simm13`	`@tmndx(S + A) & 0x3ff`
`R_SPARC_TLS_LDM_ADD`	`62`	None	Refer to the explanation following this table.
`R_SPARC_TLS_LDM_CALL`	`63`	`V-disp30`	Refer to the explanation following this table.
`R_SPARC_TLS_LDO_HIX22`	`64`	`T-simm22`	`@dtpoff(S + A) >> 10`
`R_SPARC_TLS_LDO_LOX10`	`65`	`T-simm13`	`@dtpoff(S + A) & 0x3ff`
`R_SPARC_TLS_LDO_ADD`	`66`	None	Refer to the explanation following this table.
`R_SPARC_TLS_IE_HI22`	`67`	`T-simm22`	`@got(@tpoff(S + A)) >> 10`
`R_SPARC_TLS_IE_LO10`	`68`	`T-simm13`	`@got(@tpoff(S + A)) & 0x3ff`
`R_SPARC_TLS_IE_LD`	`69`	None	Refer to the explanation following this table.
`R_SPARC_TLS_IE_LDX`	`70`	None	Refer to the explanation following this table.
`R_SPARC_TLS_IE_ADD`	`71`	None	Refer to the explanation following this table.
`R_SPARC_TLS_LE_HIX22`	`72`	`T-imm22`	`(@tpoff(S + A) ^0xffffffffffffffff) >> 10`
`R_SPARC_TLS_LE_LOX10`	`73`	`T-simm13`	`(@tpoff(S + A) & 0x3ff) \| 0x1c00`
`R_SPARC_TLS_DTPMOD32`	`74`	`V-word32`	`@dtpmod(S + A)`
`R_SPARC_TLS_DTPMOD64`	`75`	`V-word64`	`@dtpmod(S + A)`
`R_SPARC_TLS_DTPOFF32`	`76`	`V-word32`	`@dtpoff(S + A)`
`R_SPARC_TLS_DTPOFF64`	`77`	`V-word64`	`@dtpoff(S + A)`
`R_SPARC_TLS_TPOFF32`	`78`	`V-word32`	`@tpoff(S + A)`
`R_SPARC_TLS_TPOFF64`	`79`	`V-word64`	`@tpoff(S + A)`

Some relocation types have semantics beyond simple calculations.

R_SPARC_TLS_GD_ADD: This relocation tags the add instruction of a GD code sequence. The register used for the GOT-pointer is the first register in the sequence. The instruction tagged by this relocation comes before the call instruction tagged by the R_SPARC_TLS_GD_CALL relocation. This relocation is used to transition between TLS models at link-edit time.
R_SPARC_TLS_GD_CALL: This relocation is handled as if it were a R_SPARC_WPLT30 relocation referencing the __tls_get_addr() function. This relocation is part of a GD code sequence.
R_SPARC_LDM_ADD: This relocation tags the first add instruction of a LD code sequence. The register used for the GOT-pointer is the first register in the sequence. The instruction tagged by this relocation comes before the call instruction tagged by the R_SPARC_TLS_GD_CALL relocation. This relocation is used to transition between TLS models at link-edit time.
R_SPARC_LDM_CALL: This relocation is handled as if it were a R_SPARC_WPLT30 relocation referencing the __tls_get_addr() function. This relocation is part of a LD code sequence.
R_SPARC_LDO_ADD: This relocation tags the final add instruction in a LD code sequence. The register which contains the object address that is computed in the initial part of the code sequence is the first register in this instruction. This relocation permits the link-editor to identify this register for code transformations.
R_SPARC_TLS_IE_LD: This relocation tags the ld instruction in the 32–bit IE code sequence. This relocation is used to transition between TLS models at link-edit time.
R_SPARC_TLS_IE_LDX: This relocation tags the ldx instruction in the 64–bit IE code sequence. This relocation is used to transition between TLS models at link-edit time.
R_SPARC_TLS_IE_ADD: This relocation tags the add instruction in the IE code sequence. The register that is used for the GOT-pointer is the first register in the sequence.