[cfe-commits] r126148 - in /cfe/trunk: include/clang/AST/Stmt.h lib/AST/Stmt.cpp lib/Sema/SemaStmt.cpp test/CodeGen/asm-inout.c

[Frits van Bommel]

On Mon, Feb 21, 2011 at 11:09 PM, Chris Lattner <sabre at nondot.org> wrote:
> add one more case of mismatched input/output constraints.
> When the mismatch is due to a larger input operand that is
> a constant, truncate it down to the size of the output.  This
> allows us to accept some cases in the linux kernel and elsewhere.
> Pedantically speaking, we generate different code than GCC, though
> I can't imagine how it would matter:

Does this handle explicit uses of registers that have operands tied to
them? (e.g. an operand tied to 'a' and '%%eax' in the asm string)

Does it handle instructions with implicit uses + input operands tied
to those registers?
For example, IIRC x86 integer division instructions implicitly use
EAX, so I think truncating an input integer tied to 'a' could matter.