SW500011 Microchip Technology, SW500011 Datasheet - Page 82

• Manufacturer Part Number: SW500011
• Description: HI-TECH X PRO FOR PIC32
• Manufacturer: Microchip Technology
• Type: Compilerr
• Series: PIC32r

Specifications of SW500011

• No. Of User Licenses: 1
• Supported Families: PIC32
• Core Architecture: PIC
• Supported Hosts: Windows XP, Vista, Linux, Mac OS X
• Software Edition: Professional
• Kit Contents: Software And Docs
• Tool Type: Compiler
• Lead Free Status / RoHS Status: Not applicable / Not applicable
• For Use With/related Products: PIC32 Series
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: 032; 778-1007; 778-1007

Register Usage Conventions
C Language Features
(a) stackframe
Figure 3.1: General Function Stack Frame
3.5.4 Function Stack Frame
Figure
3.1
illustrates the general arrangement of function stack frames used by the compiler.
3.6 Register Usage Conventions
Some of the general purpose registers of the device have been dedicated (depending on context) to
certain roles. All functions (both mips32r2 and mips16e) with a return type equal to or less than 4
bytes will return their value in register 2 (v0). See also 3.5.3. Register 28 (gp) is initialised in the
runtime startup code with the centre address of KSEG1 DRM to allow more efficient access of data
and bss objects in RAM. Register 29 (sp) serves as the program’s stack pointer and is initialised
in the runtime startup code. The compiler does not make use of the dedicated stack frame pointer
register. Register 30 (fp/s8)is initialised in the runtime startup code with the centre address of the
const psect to allow more efficient access of constant data in ROM. Therefore the const psect is
limited by a maximum size (padding included) of 64KB. Where programs require more constant
data the excess will be allocated to the constfar psect. See
2.6.48
for more information on the
--RUNTIME option. Register 31 (ra) is used to store the return address of the most recent function
call. In leaf functions (functions which occur only as leaf nodes in all call graphs) the contents of this
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