[lld] [libcxxabi] [flang] [clang-tools-extra] [libc] [libcxx] [lldb] [llvm] [clang] [compiler-rt] [RISCV] Support Global Dynamic TLSDESC in the RISC-V backend (PR #66915)

[Fangrui Song via llvm-commits]

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@@ -0,0 +1,44 @@
+# RUN: llvm-mc -filetype=obj -triple riscv32 < %s --defsym RV32=1  | llvm-objdump -d -M no-aliases - | FileCheck %s --check-prefixes=INST,RV32
+# RUN: llvm-mc -filetype=obj -triple riscv64 < %s | llvm-objdump -d -M no-aliases - | FileCheck %s --check-prefixes=INST,RV64
+
+# RUN: not llvm-mc -triple riscv32 < %s --defsym RV32=1 --defsym ERR=1 2>&1 | FileCheck %s --check-prefixes=ERR
+# RUN: not llvm-mc -triple riscv64 < %s --defsym ERR=1 2>&1 | FileCheck %s --check-prefixes=ERR
+
+start:                                  # @start
+# %bb.0:                                # %entry
+.Ltlsdesc_hi0:
+	auipc a0, %tlsdesc_hi(a-4)
+	# INST: auipc a0, 0x0
+	auipc	a0, %tlsdesc_hi(unspecified)
+	# INST: auipc a0, 0x0
+.ifdef RV32
+	lw	a1, %tlsdesc_load_lo(.Ltlsdesc_hi0)(a0)
+	# RV32: lw a1, 0x0(a0)
+.else
+	ld	a1, %tlsdesc_load_lo(.Ltlsdesc_hi0)(a0)
+	#RV64: ld a1, 0x0(a0)
+.endif
+	addi	a0, a0, %tlsdesc_add_lo(.Ltlsdesc_hi0)
+	# INST: addi a0, a0, 0x0
+	jalr	t0, 0(a1), %tlsdesc_call(.Ltlsdesc_hi0)
+	# INST: jalr t0, 0x0(a1)
+	add	a0, a0, tp
+	# INST: add a0, a0, tp
+	ret
+
+## Check invalid usage
+.ifdef ERR
+	auipc x1, %tlsdesc_call(foo) # ERR: :[[@LINE]]:12: error: operand must be a symbol with a %pcrel_hi/%got_pcrel_hi/%tls_ie_pcrel_hi/%tls_gd_pcrel_hi/%tlsdesc_hi modifier or an integer in the range
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MaskRay wrote:

Note: `[[@LINE]]` is deprecated. Use `[[#@LINE]]`

https://github.com/llvm/llvm-project/pull/66915