Method Switch

core/codegen/builder.go:267–307

Switch builds a switch statement.

(cases []SwitchCase, defaultCase func())

// Switch builds a switch statement.
func (b *Builder) Switch(cases []SwitchCase, defaultCase func()) {
	tests := make([]llvm.BasicBlock, len(cases))
	blocks := make([]llvm.BasicBlock, len(cases))
	for i := range cases {
		tests[i] = b.m.ctx.AddBasicBlock(b.function.llvm, fmt.Sprintf("switch_case_%d_test", i))
		blocks[i] = b.m.ctx.AddBasicBlock(b.function.llvm, fmt.Sprintf("switch_case_%d_block", i))
	}

	var defaultBlock llvm.BasicBlock
	if defaultCase != nil {
		defaultBlock = b.m.ctx.AddBasicBlock(b.function.llvm, "switch_case_default")
		tests = append(tests, defaultBlock)
	}

	exit := b.m.ctx.AddBasicBlock(b.function.llvm, "end_switch")

	b.llvm.CreateBr(tests[0])

	for i, c := range cases {
		i, c := i, c
		b.block(tests[i], llvm.BasicBlock{}, func() {
			conds := c.Conditions()
			match := conds[0]
			for _, c := range conds[1:] {
				match = b.Or(match, c)
			}
			next := exit
			if i+1 < len(tests) {
				next = tests[i+1]
			}
			b.llvm.CreateCondBr(match.llvm, blocks[i], next)
		})
		b.block(blocks[i], exit, c.Block)
	}

	if defaultCase != nil {
		b.block(defaultBlock, exit, defaultCase)
	}

	b.setInsertPointAtEnd(exit)
}

// Return returns execution of the function with the given value
func (b *Builder) Return(val *Value) {