// COM: Test the trampoline fallback path for ds_*_addtid_b32 when no NOP // COM: sled is available. With zero NOP padding inside the kernel, // COM: emitReplacementCode falls back to emitToTrampoline: the original // COM: ADDTID is rewritten to s_branch and the 6-instruction expansion // COM: (lane-id math + 20-bit M0 mask + ds_load_b32) is appended after // COM: .text via growWithTrampolines. Companion to hotswap-trampoline- // COM: addtid.s which exercises the in-place NOP-sled path on the same // COM: opcode. // COM: // COM: DISASM convention: the kernel-local sequence (s_branch, structural // COM: s_nop pad, s_wait_dscnt, s_endpgm) is checked with a strict // COM: DISASM-NEXT chain. The s_nop is structural: ds_load_addtid_b32 is // COM: 8 bytes, s_branch is 4 bytes, so emitToTrampoline always pads the // COM: tail half of the original instruction slot with one s_nop -- pinning // COM: it here catches any change to that padding scheme. The trampoline // COM: body lives in a separate region appended by growWithTrampolines, so // COM: the second block uses a non-consecutive 'DISASM:' on v_mbcnt_lo to // COM: skip over the kernel terminator and any padding the assembler emits // COM: between regions, then DISASM-NEXT chains every body instruction so // COM: regressions in the math sequence, the 20-bit mask, or the operand // COM: order of ds_load_b32 are caught. // RUN: %clang -target amdgcn-amd-amdhsa -mcpu=gfx1250 -nostdlib %s -o %t.elf // RUN: hotswap-rewrite %t.elf \ // RUN: amdgcn-amd-amdhsa--gfx1250 amdgcn-amd-amdhsa--gfx1250 \ // RUN: --output %t.out.elf \ // RUN: | %FileCheck --check-prefix=API %s // API: RESULT: SUCCESS // RUN: %llvm-objdump -d %t.out.elf | %FileCheck --check-prefix=DISASM %s // ---- Kernel: ds_load_addtid_b32 with no sled -------------------------------- // // COM: Inside the kernel function the original ADDTID is gone; an s_branch // COM: forward replaces it. The surrounding s_wait_dscnt and s_endpgm are // COM: untouched. // DISASM-LABEL: : // DISASM-NOT: ds_load_addtid_b32 // DISASM: s_branch // DISASM-NEXT: s_nop 0 // DISASM-NEXT: s_wait_dscnt 0x0 // DISASM-NEXT: s_endpgm // COM: Trampoline body appended after .text: lane-id math, 20-bit M0 mask // COM: (matches B0's DS-unit M0 read width and is a no-op for any // COM: conforming M0 value), ds_load_b32 with the original offset:128 // COM: folded into the DS encoding, then s_branch back to the instruction // COM: following the original ADDTID site. All operand-pinned so that an // COM: offset/operand/shift/scalar-source regression is caught here. // DISASM: v_mbcnt_lo_u32_b32 v5, -1, 0 // DISASM-NEXT: v_mbcnt_hi_u32_b32 v5, -1, v5 // DISASM-NEXT: v_lshlrev_b32_e32 v5, 2, v5 // DISASM-NEXT: v_add_nc_u32_e32 v5, m0, v5 // DISASM-NEXT: v_and_b32_e32 v5, 0xfffff, v5 // DISASM-NEXT: ds_load_b32 v5, v5 offset:128 // DISASM-NEXT: s_branch .amdgcn_target "amdgcn-amd-amdhsa--gfx1250" .text .globl test_addtid_nosled .p2align 8 .type test_addtid_nosled,@function test_addtid_nosled: ds_load_addtid_b32 v5 offset:128 s_wait_dscnt 0x0 s_endpgm .Ltest_addtid_nosled_end: .size test_addtid_nosled, .Ltest_addtid_nosled_end-test_addtid_nosled .rodata .p2align 8 .amdhsa_kernel test_addtid_nosled .amdhsa_next_free_vgpr 6 .amdhsa_next_free_sgpr 1 .end_amdhsa_kernel // COM: Idempotency: rewriting the patched output a second time must // COM: produce identical bytes. The trampoline body uses plain ds_load_b32 // COM: (no ADDTID mnemonic), so the dispatcher leaves it untouched on // COM: subsequent runs. // RUN: hotswap-rewrite %t.out.elf \ // RUN: amdgcn-amd-amdhsa--gfx1250 amdgcn-amd-amdhsa--gfx1250 \ // RUN: --check-idempotent \ // RUN: | %FileCheck --check-prefix=IDEM %s // IDEM: IDEMPOTENT: YES