Commit Graph

4 Commits

Author SHA1 Message Date
Rafael Espindola 464fe024c5 Use "weak alias" instead of "alias weak"
Before this patch we had

@a = weak global ...
but
@b = alias weak ...

The patch changes aliases to look more like global variables.

Looking at some really old code suggests that the reason was that the old
bison based parser had a reduction for alias linkages and another one for
global variable linkages. Putting the alias first avoided the reduce/reduce
conflict.

The days of the old .ll parser are long gone. The new one parses just "linkage"
and a later check is responsible for deciding if a linkage is valid in a
given context.

llvm-svn: 214355
2014-07-30 22:51:54 +00:00
Rafael Espindola 9aadcc4c0e s/compiler_used/compiler.used/.
We were incorrectly using compiler_used instead of compiler.used. Unfortunately
the passes using the broken name had tests also using the broken name.

llvm-svn: 186705
2013-07-19 18:44:51 +00:00
Rafael Espindola a82555c0f8 Change how globalopt handles aliases in llvm.used.
Instead of a custom implementation of replaceAllUsesWith, we just call
replaceAllUsesWith and recreate llvm.used and llvm.compiler-used.

This change is particularity interesting because it makes llvm see
through what clang is doing with static used functions in extern "C"
contexts. With this change, running clang -O2 in

extern "C" {
  __attribute__((used)) static void foo() {}
}

produces

@llvm.used = appending global [1 x i8*] [i8* bitcast (void ()* @foo to
i8*)], section "llvm.metadata"
define internal void @foo() #0 {
entry:
  ret void
}

llvm-svn: 183756
2013-06-11 17:48:06 +00:00
Rafael Espindola 007521673b Don't replace an alias in llvm.used with its target.
When we replace an internal alias with its target, be careful not to
replace the entry in llvm.used (and llvm.compiler_used).

llvm-svn: 181524
2013-05-09 17:22:59 +00:00