Shared Source CLI Essentials

JIT Compiler Macros

The JIT compiler uses a large system of interrelated macros. The following verifier macros can be found in clr/src/fjit/fjitverifier.h:

CHECK_STACK

CHECK_STACK_SIZE

When verification is turned on, these macros will verify that the evaluation stack is deep enough to be valid or that it matches an exact depth.

FJIT_FAIL

This macro will cause the current JIT compilation to fail and return an error code.

VALIDITY_CHECK

If verification is turned on, this macro will conditionally terminate a JIT compilation and return an error code that indicates that invalid code was provided.

VERIFICATION_CHECK

If verification is turned on, this macro will conditionally emit code to throw a verification exception. It is used within the JIT compiler.

There is a large series of macros used to emit code, which is contained in clr/src/fjit/fjitdef.h and is augmented by platform-specific redefinition files that can be found in subdirectories named after their processor targets:

x86_*

These are low-level, x86-specific macros used by fjitdef.h.

ppc_*

These are low-level, PowerPC-specific macros used by fjitdef.h.

emit_*

These are high-level, macros defined in fjitdef.h that can be redefined by platform-specific low-level macros.

emit_<IL OPCODE NAME>_*

These are portable macros that implement opcodes, and are frequently separated by the size of the stack and frame registers.

ARG_*

These definitions represent argument registers.

RETURN_*

These definitions represent return value registers. ...