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.text
.globl greater_than_ten
.type greater_than_ten, @function
// bool greater_than_ten(double a, uint64_t b);
greater_than_ten:
// Upon entry a -> fa0; and b -> a0. That is, the ABI increments the
//(f)a<n> register per argument type.
// Change the rounding to "Rounds Towards Zero" (bits: 0b001).
li t0, 0b001
fsrm t0
// Convert the second parameter to double.
fcvt.d.lu ft0, a0
// ret = a + b
fadd.d fa0, fa0, ft0
// ret = (ret * b) + b
fmv.d ft1, ft0
fmadd.d fa0, fa0, ft0, ft1
// Now we need to compare the number with 10.0. There are multiple ways to
// load a floating point immediate:
// 1. Loading an integer immediate and then convert it into a double. This
// is discouraged on the RISC-V assembly manual.
// 2. Load a double with `fld` from a memory location on the data section.
// 3. Load a floating point immediate with `fli` (requires the `Zfa`
// extension).
// I don't have the `Zfa` extension on my board, so I'm opting for the
// second way.
fld ft1, .TEN, t0
fle.d a0, ft1, fa0
ret
.data
.TEN:
.double 10.0
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