3.18.35 picoChip Options
These ‘-m’ options are defined for picoChip implementations:
- Set the instruction set, register set, and instruction scheduling
parameters for array element type ae_type. Supported values
for ae_type are ‘ANY’, ‘MUL’, and ‘MAC’.
-mae=ANY selects a completely generic AE type. Code
generated with this option runs on any of the other AE types. The
code is not as efficient as it would be if compiled for a specific
AE type, and some types of operation (e.g., multiplication) do not
work properly on all types of AE.
-mae=MUL selects a MUL AE type. This is the most useful AE type
for compiled code, and is the default.
-mae=MAC selects a DSP-style MAC AE. Code compiled with this
option may suffer from poor performance of byte (char) manipulation,
since the DSP AE does not provide hardware support for byte load/stores.
- Enable the compiler to directly use a symbol name as an address in a
load/store instruction, without first loading it into a
register. Typically, the use of this option generates larger
programs, which run faster than when the option isn't used. However, the
results vary from program to program, so it is left as a user option,
rather than being permanently enabled.
- Disables warnings about the generation of inefficient code. These
warnings can be generated, for example, when compiling code that
performs byte-level memory operations on the MAC AE type. The MAC AE has
no hardware support for byte-level memory operations, so all byte
load/stores must be synthesized from word load/store operations. This is
inefficient and a warning is generated to indicate
that you should rewrite the code to avoid byte operations, or to target
an AE type that has the necessary hardware support. This option disables