IF Statement Generation

Code for an intermediate code statement of the form (if c p1 p2) can be generated as follows:

1. Generate code for the condition c using the arithmetic expression code generator. Note that a cmp instruction should be generated for all comparison operators, regardless of which comparison is used.

2. Generate the appropriate branch-on-condition instruction, denoted bra c below, by table lookup depending on the comparison operator.

    bra c   .L1
    nop
    p2             ! "else"
    ba      .L2
    nop
.L1:
    p1             ! "then"
.L2:

The following branch table can be used:

op	=		<			>
c	be	bne	bl	ble	bge	bg
-c	bne	be	bge	bg	bl	ble

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