Hi! I'm trying to implement word2Double# and I've looked at how e.g. LLVM does it. LLVM outputs quite clever branchless code that uses two predefined constants in the .data section. Is it possible to add contents to the current .data section from a function in the NatM monad e.g. coerceWord2FP :: Width -> Width -> CmmExpr -> NatM Register ? Cheers, Johan P.S. Given this C code double f(unsigned long long u) { return u; } LLVM generates this rather clever code: .section __TEXT,__text,regular,pure_instructions .section __TEXT,__literal8,8byte_literals .align 3 LCPI1_0: .long 1602224128 // constant we'd like to ouput .long 0 // constant we'd like to ouput .section __TEXT,__text,regular,pure_instructions .globl _f .align 4, 0x90 _f: pushl %ebp movl %esp, %ebp subl $16, %esp movl 8(%ebp), %eax movl 12(%ebp), %ecx movl %ecx, -4(%ebp) movl %eax, -8(%ebp) testl %ecx, %ecx // check sign sets %al // check sign xorb $1, %al // check sign movzbl %al, %eax // 0 if signed fildll -8(%ebp) // load integer fadds LCPI1_0(,%eax,4) // add one of two constants fstpl -16(%ebp) // store and pop fldl -16(%ebp) addl $16, %esp popl %ebp ret