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[mips] Reduce number of instructions used for loading a global symbol's value
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Authored by atanasyan on Wed, Aug 21, 1:39 PM.

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Summary

Now lw/sw $reg, sym+offset pseudo instructions for global symbol sym are lowering into the following three instructions.

lw     $reg, %got(symbol)($gp)
addiu  $reg, $reg, offset
lw/sw  $reg, 0($reg)

It's possible to reduce the number of instructions by taking the offset in account in the final lw/sw command. This patch implements that optimization.

lw     $reg, %got(symbol)($gp)
lw/sw  $reg, offset($reg)

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Repository
rL LLVM