[X86-64] Only treat PC-relative globals as memory content if they are dynamically relocated #121
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aaronsm
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Dec 27, 2021
… dynamically relocated This makes sure that both of the following work as expected: 1. mov eax, [rip + myglob@GOTPCREL] used for shared libraries compiled to position independent code (-fPIC) Here myglob is dynamically relocated through the GOT 2. mov eax, [rip + myglob] used for non-PIC code to access a global directly without any indirection through the GOT [Test] Added one test to verify RIP-relative globals work as expected
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This makes sure that both of the following work as expected:
mov eax, [rip + myglob@GOTPCREL]used for shared libraries compiled to position independent code (-fPIC). Here myglob is dynamically relocated through the GOT
mov eax, [rip + myglob]used for non-PIC code to access a global directly without any indirection through the GOT
The added test verifies that 2. works, which was broken previously (the code would print the address of
iinstead of its value). The testsglobalvar-test.cand dhrystone verify that 1. works as expected.I've implemented this by adding a set that keeps track of global variables that have
DynRelocType == ELF::R_X86_64_GLOB_DAT.