llvm-6502/lib/Target/ARM/README.txt

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//===---------------------------------------------------------------------===//
// Random ideas for the ARM backend.
//===---------------------------------------------------------------------===//
Consider implementing a select with two conditional moves:
cmp x, y
moveq dst, a
movne dst, b
----------------------------------------------------------
%tmp1 = shl int %b, ubyte %c
%tmp4 = add int %a, %tmp1
compiles to
add r0, r0, r1, lsl r2
but
%tmp1 = shl int %b, ubyte %c
%tmp4 = add int %tmp1, %a
compiles to
mov r1, r1, lsl r2
add r0, r1, r0
----------------------------------------------------------
add an offset to FLDS/FLDD addressing mode
----------------------------------------------------------