[llvm] [RISCV] Add Vendor Reloc and Fallback Names (PR #116974)

[Fangrui Song via llvm-commits]

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@@ -0,0 +1,43 @@
+# RUN: llvm-mc -triple riscv32 < %s \
+# RUN:   | FileCheck -check-prefix=CHECK-ASM %s
+# RUN: llvm-mc -triple riscv64 < %s \
+# RUN:   | FileCheck -check-prefix=CHECK-ASM %s
+
+# RUN: llvm-mc -filetype=obj -triple riscv32 < %s \
+# RUN:   | llvm-objdump -dr -M no-aliases - \
+# RUN:   | FileCheck -check-prefix=CHECK-OBJ %s
+# RUN: llvm-mc -filetype=obj -triple riscv64 < %s \
+# RUN:   | llvm-objdump -dr -M no-aliases  - \
+# RUN:   | FileCheck -check-prefix=CHECK-OBJ %s
+
+  # CHECK-ASM: .text
+
+  # If `.set` is used instead, the relocation expression will be evaluated.
+  # This leaves an undef, global symbol called VENDOR_NAME, which I'm not happy
+  # about.
+  .global VENDOR_NAME
+
+  # CHECK-OBJ: <.text>:
+
+  nop
+  # CHECK-ASM: nop
+  # CHECK-OBJ: addi zero, zero, 0x0
+
+  .reloc ., R_RISCV_VENDOR,    VENDOR_NAME
+  .reloc ., R_RISCV_CUSTOM192, my_foo + 1
+  addi a0, a0, 0
+  # CHECK-ASM: [[L1:.L[^:]+]]:
+  # CHECK-ASM-NEXT: .reloc [[L1]], R_RISCV_VENDOR, VENDOR_NAME
+  # CHECK-ASM-NEXT: [[L2:.L[^:]+]]:
+  # CHECK-ASM-NEXT: .reloc [[L2]], R_RISCV_CUSTOM192, my_foo+1
+  # CHECK-ASM-NEXT: mv a0, a0
+
+  # CHECK-OBJ: addi a0, a0, 0
+  # CHECK-OBJ-NEXT: R_RISCV_VENDOR    VENDOR_NAME
+  # CHECK-OBJ-NEXT: R_RISCV_CUSTOM192 my_foo+0x1
+
+  nop
+  # CHECK-ASM: nop
+  # CHECK-OBJ: addi zero, zero, 0x0
+
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MaskRay wrote:

delete trailing blank lines

https://github.com/llvm/llvm-project/pull/116974