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9.31.3 Nios II Machine Relocations

Extract the upper 16 bits of expression and add one if the 15th bit is set.

The value of %hiadj(expression) is:

          ((expression >> 16) & 0xffff) + ((expression >> 15) & 0x01)

The %hiadj relocation is intended to be used with the addi, ld or st instructions along with a %lo, in order to load a 32-bit constant.

          movhi r2, %hiadj(symbol)
          addi r2, r2, %lo(symbol)

Extract the upper 16 bits of expression.

Extract the lower 16 bits of expression.

Subtract the value of the symbol _gp from expression.

The intention of the %gprel relocation is to have a fast small area of memory which only takes a 16-bit immediate to access.

          	.section .sdata
          	.int 123
          	.section .text
          	ldw r4, %gprel(fastint)(gp)

These relocations support the ABI for Linux Systems documented in the Nios II Processor Reference Handbook.