discuss.txt

1. Instructions to be added:

    ####### INTEGER OPERATIONS ###########
    ------- Cranelift --------------------
    1. sgt, ugt, sge, uge - souper canonicalizes all greater-than operations
       to less-than. Do we still add these?
    2. icmp_imm<cond> op1, op2 - https://cranelift.readthedocs.io/en/latest/ir.html#inst-icmp_imm
    3. ifcmp - https://cranelift.readthedocs.io/en/latest/ir.html#inst-ifcmp
    4. icmp_imm - https://cranelift.readthedocs.io/en/latest/ir.html#inst-ifcmp_imm
    5. iadd_imm, isub_imm, imul_imm
    6. iadd_cin, iadd_cout, iadd_carry (what are the equivalent souper instructions here?)
       https://cranelift.readthedocs.io/en/latest/ir.html#inst-iadd_cin
    7. isub_bin, isub_bout, isub_borrow - (what are the equivalent souper ISA?)
       Subtract with borrow in, borrow out and borrow
       https://cranelift.readthedocs.io/en/latest/ir.html#inst-isub_borrow
    8. sdiv, udiv
    9. sdiv_imm, udiv_imm
    10. srem, urem
    11. srem_imm, urem_imm
    
    ------- Souper ISA --------------------
    1. UB insts: addnuw, addnsw, addnw, subnuw, subnsw, subnw, mulnsw, mulnuw, mulnw
    2. udiv, sdiv
    3. udivexact, sdivexact -- corresponding Cranelift ISA?
    4. srem, urem
    5. sadd.with.overflow, uadd.with.overflow
    6. extract value
    7. trunc - no cranelift insts
    8. zext, sext - no cranelift insts
    

    ########### BITWISE OPERATIONS ###########
    ----------- Cranelift ISA ----------------
    1. band, bor, bxor - DONE 
    2. band_imm, bor_imm, bxor_imm
    3. bnot, band_not, bor_not, bxor_not -- no souper ISA for this? Do we add these insts in Souper temporarily?
       https://cranelift.readthedocs.io/en/latest/ir.html#inst-bnot
    4. rotl, rotr - rotate instruction -- add in souper??
       https://cranelift.readthedocs.io/en/latest/ir.html#inst-rotl
    5. rotl_imm, rotr_imm
    6. Integer shift left instruction:
       ishl -- DONE - souper has shl only and other UB insts like, shlnsw, shlnuw, shlnw => what to do here?
    7. ishl_imm
    8. Signed.unsigned shift right
       ushr, sshr -- DONE - souper has lshr, ashr (to map easily)
    9. sshr_imm, ushr_imm
    

    ------- Souper ISA --------------------
    1. and, or, xor - DONE
    2. shl, lshr, ashr - DONE
    3. UB -> shlnuw, shlnsw, shlnw
    4. LShrExact, AShrExact -- no Cranelift insts here? what to do?



    ########### INRINSICS ###########
    ----------- Cranelift ISA ----------------
    1. clz - DONE - count leading zeros - https://cranelift.readthedocs.io/en/latest/ir.html#inst-clz
    2. ctz - - DONE - trailing zeros
    3. popcnt - DONE
    4. cls - count leading sign bits -- same as sign bits dfa -- do we add new inst in souper or wait for this inst to
    map to 
    
    ------- Souper ISA --------------------
    1. cttz, ctlz, ctpop - DONE
    2. bswap -- no cranelift inst for this


2. handle widths in matcher?

3. handle diff. parameters in matcher?