tinygo-org/tinygo
1
0
Fork 0
mirror of https://github.com/tinygo-org/tinygo.git synced 2026-08-07 20:43:40 +00:00
Code Issues Packages Projects Releases 6 Wiki Activity

compiler: implement complex multiplication

Browse Source
This commit is contained in:
Ayke van Laethem
2019-05-04 22:48:44 +02:00
committed by Ron Evans
parent 638bc17eeb
commit d7460b945e
3 changed files with 23 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files
compiler/compiler.go
+19
View File
@@ -1837,6 +1837,25 @@ func (c *Compiler) parseBinOp(op token.Token, typ types.Type, x, y llvm.Value, p
cplx = c.builder.CreateInsertValue(cplx, r, 0, "")
cplx = c.builder.CreateInsertValue(cplx, i, 1, "")
return cplx, nil
case token.MUL:
// Complex multiplication follows the current implementation in
// the Go compiler, with the difference that complex64
// components are not first scaled up to float64 for increased
// precision.
// https://github.com/golang/go/blob/170b8b4b12be50eeccbcdadb8523fb4fc670ca72/src/cmd/compile/internal/gc/ssa.go#L2089-L2127
// The implementation is as follows:
// r := real(a) * real(b) - imag(a) * imag(b)
// i := real(a) * imag(b) + imag(a) * real(b)
// Note: this does NOT follow the C11 specification (annex G):
// http://www.open-std.org/jtc1/sc22/wg14/www/docs/n1548.pdf#page=549
// See https://github.com/golang/go/issues/29846 for a related
// discussion.
r := c.builder.CreateFSub(c.builder.CreateFMul(r1, r2, ""), c.builder.CreateFMul(i1, i2, ""), "")
i := c.builder.CreateFAdd(c.builder.CreateFMul(r1, i2, ""), c.builder.CreateFMul(i1, r2, ""), "")
cplx := llvm.Undef(c.ctx.StructType([]llvm.Type{r.Type(), i.Type()}, false))
cplx = c.builder.CreateInsertValue(cplx, r, 0, "")
cplx = c.builder.CreateInsertValue(cplx, i, 1, "")
return cplx, nil
default:
return llvm.Value{}, c.makeError(pos, "todo: binop on complex number: "+op.String())
}