Steps for finding the C/370 parameter list

Perform the following steps to locate a parameter in the Language Environment dump:

Identify the address of the start of the parameter list. A pointer to the parameter list is passed to the called function in register 1. This is the address of the start of the parameter list. Figure 1 shows an example code for the parameter variable.
Figure 1. Example code for parameter variable
```
func0() {
⋮
 func1(a1,a2);
⋮
}

func1(int ppx, int pp0) {
⋮
}
```
Parameters ppx and pp0 correspond to copies of a1 and a2 in the stack frame belonging to func0.
Use the address of the start of the parameter list to find the register and offset in the partial storage offset listing. As shown in the following example, the offset is 4 (X'4') from register 1.
```
pp0     62-0:62    Class = parameter,   Location = 4(r1),    Length = 4
```
Determine the value of GPR1 in the Saved Registers section for the function that called the function you are interested in.
Add this base address to the offset of the parameter.

When you are done, the contents of the variable can then be read in the DSA frame section corresponding to the function the parameter was passed from.