[llvm] [ARMAsmBackend] Add checks for relocation addends in assembler (PR #109969)

[Jonathan Cohen via llvm-commits]

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@@ -0,0 +1,62 @@
+// RUN: not llvm-mc -triple armv7-apple-darwin -filetype=obj %s 2>&1 | FileCheck %s
+
+// Check that the relocation size is valid.
+// Check lower bound of edge case.
+_foo1_valid:
+    // CHECK-NOT: :[[@LINE+1]]:{{[0-9]+}}: error: Relocation out of range
+    b   _foo1_valid+0x2000004
+// Check outside of range of the largest accepted positive number
+_foo1:
+    // CHECK: :[[@LINE+1]]:{{[0-9]+}}: error: Relocation out of range
+    b   _foo1+0x2000008
+
+// Check Same as above, for smallest negative value
+_foo2_valid:
+    // CHECK-NOT: :[[@LINE+1]]:{{[0-9]+}}: error: Relocation out of range
+    b   _foo2_valid-0x1FFFFF8
+_foo2:
+    // CHECK: :[[@LINE+1]]:{{[0-9]+}}: error: Relocation out of range
+    b   _foo2-0x1FFFFFC
+
+// Edge case - subtracting positive number
+_foo3:
+    // CHECK: :[[@LINE+1]]:{{[0-9]+}}: error: Relocation out of range
+    b   _foo3-0x2000010
+
+// Edge case - adding negative number
+_foo4:
+    // CHECK: :[[@LINE+1]]:{{[0-9]+}}: error: Relocation out of range
+    b   _foo4+0x2000008
+
+_foo5:
+    // CHECK: :[[@LINE+1]]:{{[0-9]+}}: error: Relocation out of range
+    bl  _foo5+0x2000008
+
+_foo6:
+    // CHECK: :[[@LINE+1]]:{{[0-9]+}}: error: Relocation out of range
+    blx _foo6+0x2000008
+
+// blx instruction is aligned to 16-bits.
+_foo7:
+    // CHECK-NOT:[[@LINE+1]]:{{[0-9]+}}: error: Relocation out of range
+    blx _foo7+0x1FFFFFE
+
+_foo8:
+    // CHECK: :[[@LINE+1]]:{{[0-9]+}}: error: Relocation out of range
+    ble _foo8+0x2000008
+
+_foo9:
+    // CHECK: :[[@LINE+1]]:{{[0-9]+}}: error: Relocation out of range
+    beq _foo9+0x2000008
+
+    // Check that the relocation alignment is valid.
----------------
jcohen-apple wrote:

Added an additional test for non blx instructions so this is more explicit.

https://github.com/llvm/llvm-project/pull/109969