arm64: introduce mov_q macro to move a constant into a 64-bit register
Implement a macro mov_q that can be used to move an immediate constant
into a 64-bit register, using between 2 and 4 movz/movk instructions
(depending on the operand)
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
diff --git a/arch/arm64/include/asm/assembler.h b/arch/arm64/include/asm/assembler.h
index 972fb55..f9b6f7a 100644
--- a/arch/arm64/include/asm/assembler.h
+++ b/arch/arm64/include/asm/assembler.h
@@ -221,4 +221,24 @@
.long \sym\()_hi32
.endm
+ /*
+ * mov_q - move an immediate constant into a 64-bit register using
+ * between 2 and 4 movz/movk instructions (depending on the
+ * magnitude and sign of the operand)
+ */
+ .macro mov_q, reg, val
+ .if (((\val) >> 31) == 0 || ((\val) >> 31) == 0x1ffffffff)
+ movz \reg, :abs_g1_s:\val
+ .else
+ .if (((\val) >> 47) == 0 || ((\val) >> 47) == 0x1ffff)
+ movz \reg, :abs_g2_s:\val
+ .else
+ movz \reg, :abs_g3:\val
+ movk \reg, :abs_g2_nc:\val
+ .endif
+ movk \reg, :abs_g1_nc:\val
+ .endif
+ movk \reg, :abs_g0_nc:\val
+ .endm
+
#endif /* __ASM_ASSEMBLER_H */