PNaCl Dynamic Linking: Force __pnacl_pso_root to be an external declaration.

tests_lit/llvm2ice_tests/external_declaration.ll

Index: tests_lit/llvm2ice_tests/external_declaration.ll
diff --git a/tests_lit/llvm2ice_tests/external_declaration.ll b/tests_lit/llvm2ice_tests/external_declaration.ll
new file mode 100644
index 0000000000000000000000000000000000000000..ef1d7b0c8d5c941966ef422cbd96c49928d60935
--- /dev/null
+++ b/tests_lit/llvm2ice_tests/external_declaration.ll
@@ -0,0 +1,11 @@
+; RUN: %if --need=allow_dump --command %p2i -i %s --target=x8632 \

[Jim Stichnoth, 2016/03/11 01:20:29]

1. It would be nice to add a brief comment at the top describing the purpose of
the test file.  Even if not all the other .ll tests do this...

2. It would probably be cleaner to remove the pnacl-sz flags that don't really
matter: --target and -O2.

[Sean Klein, 2016/03/11 01:27:45]

Done.

+; RUN    --filetype=asm --args -O2 -nonsfi=0 \

[Jim Stichnoth, 2016/03/11 01:20:29]

s/RUN/RUN:/
otherwise these options are just ignored :)

Probably the default filetype is iasm and default nonsfi is 0, so this works
accidentally.

[Sean Klein, 2016/03/11 01:27:45]

Yikes, my bad. Fixed.

+; RUN:   | %if --need=allow_dump --command FileCheck %s
+
+; Verify that "__pnacl_pso_root", a specially named symbol, is made

[Jim Stichnoth, 2016/03/11 01:20:29]

reflow comment to 80-col

[Sean Klein, 2016/03/11 01:27:45]

Done.

+; global, but other global variables are not.
+@__pnacl_pso_root = constant [4 x i8] c"abcd";
+@__pnacl_pso_not_root = constant [4 x i8] c"efgh";
+
+; CHECK: .globl __pnacl_pso_root
+; CHECK-NOT: .globl __pnacl_pso_not_root