In sparc, setjmp stores only the registers %fp, %sp, %i7 and %o7. longjmp restores
the stack, and the callee-saved registers (all local/in registers: %i0-%i7, %l0-%l7)
using the stored %fp and register windows. However, this does not guarantee that the longjmp
will restore the registers, as they were when the setjmp was called. This is because these
registers may be clobbered after returning from setjmp, but before calling longjmp.
This patch prevents the registers %i0-%i5, %l0-l7 to live across the setjmp call using the register mask.
llvm-svn: 190033
This field specifies registers that are preserved across function calls,
but that should not be included in the generates SaveList array.
This can be used ot generate regmasks for architectures that save
registers through other means, like SPARC's register windows.
llvm-svn: 189084
All arguments are formally assigned to stack positions and then promoted
to floating point and integer registers. Since there are more floating
point registers than integer registers, this can cause situations where
floating point arguments are assigned to registers after integer
arguments that where assigned to the stack.
Use the inreg flag to indicate 32-bit fragments of structs containing
both float and int members.
The three-way shadowing between stack, integer, and floating point
registers requires custom argument lowering. The good news is that
return values are passed in the exact same way, and we can share the
code.
Still missing:
- Update LowerReturn to handle structs returned in registers.
- LowerCall.
- Variadic functions.
llvm-svn: 178958
This is far from complete, but it is enough to make it possible to write
test cases using i64 arguments.
Missing features:
- Floating point arguments.
- Receiving arguments on the stack.
- Calls.
llvm-svn: 178523
lowering over to SparcCallingConv.td. We can't make the switch
yet because we can't say to pass f64 registers in 2 x i32 registers
with the td file yet.
llvm-svn: 48449
Venkatraman Govindaraju