[llvm] [llvm][MC][ARM][Assembly] Emit relocations for ADRs and big-endian targets (PR #73834)

[Eleanor Bonnici via llvm-commits]

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@@ -0,0 +1,23 @@
+@ RUN: llvm-mc -filetype=obj --triple=thumbv6m-none-eabi %s -o %t
+@ RUN: llvm-readelf -r %t | FileCheck %s --check-prefix=RELOC
+@ RUN: llvm-objdump -d --triple=thumbv6m-none-eabi %t | FileCheck %s --check-prefix=ADDEND
+
+    .section .text._func1, "ax"
+
+    .balign 4
+    .global _func1
+    .type _func1, %function
+_func1:
+    adr r0, _func2
+@ RELOC: R_ARM_THM_PC8
+    bx lr
+
+// Checking the encoding only, as the disassembly is not quite correct here.
+
+// Thumb16 encoding supports only adding of the encoded immediate (not
+// subtracting, see [Arm ARM]), therefore sign change is required if the pcrel
+// offset is negative. This makes the calculation of the addend for
+// R_ARM_THM_PC8 more complex, for details see [ELF for the Arm 32-bit
+// architecture].
+@ ADDEND: a0ff
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eleanor-arm wrote:

I've updated it in the next version. Hopefully that works. 

https://github.com/llvm/llvm-project/pull/73834