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a926d84c4b
The previous code that was supposed to handle this didn't work
since parsing of inline method definitions is delayed to the end
of the outer class definition. Thus, when HandleTagDeclDefinition()
got called for the inner class, the inline functions in that class
had not been parsed yet.
Richard suggested that the way to do this is by handling inline
method definitions through a new ASTConsumer callback.
I really wanted to call ASTContext::DeclMustBeEmitted() instead of
checking for attributes, but doing that causes us to compute linkage,
and then we fail with "error: unsupported: typedef changes linkage
of anonymous type, but linkage was already computed" on tests like
this: (from SemaCXX/undefined-internal.cpp) :-/
namespace test7 {
typedef struct {
void bar();
void foo() { bar(); }
} A;
}
Differential Revision: http://reviews.llvm.org/D3809
llvm-svn: 209549
IRgen optimization opportunities. //===---------------------------------------------------------------------===// The common pattern of -- short x; // or char, etc (x == 10) -- generates an zext/sext of x which can easily be avoided. //===---------------------------------------------------------------------===// Bitfields accesses can be shifted to simplify masking and sign extension. For example, if the bitfield width is 8 and it is appropriately aligned then is is a lot shorter to just load the char directly. //===---------------------------------------------------------------------===// It may be worth avoiding creation of alloca's for formal arguments for the common situation where the argument is never written to or has its address taken. The idea would be to begin generating code by using the argument directly and if its address is taken or it is stored to then generate the alloca and patch up the existing code. In theory, the same optimization could be a win for block local variables as long as the declaration dominates all statements in the block. NOTE: The main case we care about this for is for -O0 -g compile time performance, and in that scenario we will need to emit the alloca anyway currently to emit proper debug info. So this is blocked by being able to emit debug information which refers to an LLVM temporary, not an alloca. //===---------------------------------------------------------------------===// We should try and avoid generating basic blocks which only contain jumps. At -O0, this penalizes us all the way from IRgen (malloc & instruction overhead), all the way down through code generation and assembly time. On 176.gcc:expr.ll, it looks like over 12% of basic blocks are just direct branches! //===---------------------------------------------------------------------===//