# RUN: %stinkytofu-opt --arch gfx1250 %s --DeadCodeEliminationPass --print-output
#
# Dead Code Elimination: remove instructions whose results are overwritten
# before being used.
# Converted from DeadCodeEliminationPassTest.

#--- Simple dead code: v0 overwritten before use → first def removed
# CHECK-LABEL: @remove_simple_dead_code
# CHECK-NOT: v_mul_f32
# CHECK: v_add_f32
# CHECK: v_mov_b32
# CHECK: v_sub_f32
# CHECK: buffer_store_b32

st.func @remove_simple_dead_code() {
^entry:
  v0 = "st.v_mul_f32"(v1, v2) { issueCycles = 1, latencyCycles = 5 }
  v3 = "st.v_add_f32"(v4, v5) { issueCycles = 1, latencyCycles = 5 }
  v0 = "st.v_mov_b32"(v7) { issueCycles = 1, latencyCycles = 1 }
  v6 = "st.v_sub_f32"(v0, v3) { issueCycles = 1, latencyCycles = 5 }
  "st.buffer_store_b32"(v40, v6) { issueCycles = 1, latencyCycles = 1 }
}

#--- Chain of dead stores: three overwrites, only last kept
# CHECK-LABEL: @chain_of_dead_code
# CHECK-NOT: v_mul_f32
# CHECK-NOT: v_add_f32
# CHECK-NOT: v_fma_f32
# CHECK: v_sub_f32
# CHECK: buffer_store_b32

st.func @chain_of_dead_code() {
^entry:
  v0 = "st.v_mul_f32"(v1, v2) { issueCycles = 1, latencyCycles = 5 }
  v0 = "st.v_add_f32"(v3, v4) { issueCycles = 1, latencyCycles = 5 }
  v0 = "st.v_fma_f32"(v5, v6, 1.0) { issueCycles = 1, latencyCycles = 5 }
  v0 = "st.v_sub_f32"(v10, v11) { issueCycles = 1, latencyCycles = 5 }
  "st.buffer_store_b32"(v40, v0) { issueCycles = 1, latencyCycles = 1 }
}

#--- Don't remove live code: all defs used
# CHECK-LABEL: @dont_remove_live_code
# CHECK: v_mul_f32
# CHECK: v_add_f32
# CHECK: v_fma_f32
# CHECK: buffer_store_b32

st.func @dont_remove_live_code() {
^entry:
  v0 = "st.v_mul_f32"(v1, v2) { issueCycles = 1, latencyCycles = 5 }
  v3 = "st.v_add_f32"(v0, v4) { issueCycles = 1, latencyCycles = 5 }
  v5 = "st.v_fma_f32"(v3, v0, 1.0) { issueCycles = 1, latencyCycles = 5 }
  "st.buffer_store_b32"(v40, v5) { issueCycles = 1, latencyCycles = 1 }
}

#--- Multiple uses keep alive: first v3 def overwritten, but v0 def is live
# CHECK-LABEL: @multiple_uses_keep_alive
# CHECK: v_mul_f32
# CHECK-NOT: v_add_f32
# CHECK: v_sub_f32
# CHECK: v_fma_f32
# CHECK: buffer_store_b32

st.func @multiple_uses_keep_alive() {
^entry:
  v0 = "st.v_mul_f32"(v1, v2) { issueCycles = 1, latencyCycles = 5 }
  v3 = "st.v_add_f32"(v0, v4) { issueCycles = 1, latencyCycles = 5 }
  v3 = "st.v_sub_f32"(v5, v6) { issueCycles = 1, latencyCycles = 5 }
  v7 = "st.v_fma_f32"(v3, v1, 1.0) { issueCycles = 1, latencyCycles = 5 }
  "st.buffer_store_b32"(v40, v7) { issueCycles = 1, latencyCycles = 1 }
}

#--- Preserve memory operations
# CHECK-LABEL: @preserve_memory_ops
# CHECK: buffer_load_b32
# CHECK: v_mul_f32
# CHECK: buffer_store_b32

st.func @preserve_memory_ops() {
^entry:
  v0 = "st.buffer_load_b32"(v40) { issueCycles = 1, latencyCycles = 100 }
  v4 = "st.v_mul_f32"(v1, v2) { issueCycles = 1, latencyCycles = 5 }
  "st.buffer_store_b32"(v41, v4) { issueCycles = 1, latencyCycles = 1 }
}

#--- All dead stores to same register: first two removed, last kept
# CHECK-LABEL: @all_dead_code
# CHECK-NOT: v_mul_f32
# CHECK-NOT: v_add_f32
# CHECK: v_sub_f32

st.func @all_dead_code() {
^entry:
  v0 = "st.v_mul_f32"(v1, v2) { issueCycles = 1, latencyCycles = 5 }
  v0 = "st.v_add_f32"(v4, v5) { issueCycles = 1, latencyCycles = 5 }
  v0 = "st.v_sub_f32"(v7, v8) { issueCycles = 1, latencyCycles = 5 }
}

#--- Interleaved live and dead: all instructions live in chain
# CHECK-LABEL: @interleaved_live_and_dead
# CHECK: v_mul_f32
# CHECK: v_add_f32
# CHECK: v_sub_f32
# CHECK: v_fma_f32
# CHECK: v_add_f32
# CHECK: buffer_store_b32

st.func @interleaved_live_and_dead() {
^entry:
  v0 = "st.v_mul_f32"(v1, v2) { issueCycles = 1, latencyCycles = 5 }
  v3 = "st.v_add_f32"(v4, v5) { issueCycles = 1, latencyCycles = 5 }
  v6 = "st.v_sub_f32"(v3, v0) { issueCycles = 1, latencyCycles = 5 }
  v7 = "st.v_fma_f32"(v8, v9, 1.0) { issueCycles = 1, latencyCycles = 5 }
  v10 = "st.v_add_f32"(v6, v7) { issueCycles = 1, latencyCycles = 5 }
  "st.buffer_store_b32"(v40, v10) { issueCycles = 1, latencyCycles = 1 }
}

#--- Constant operands: all live
# CHECK-LABEL: @constant_operands
# CHECK: v_mul_f32
# CHECK: v_add_f32
# CHECK: v_fma_f32
# CHECK: buffer_store_b32

st.func @constant_operands() {
^entry:
  v0 = "st.v_mul_f32"(v1, 2.0) { issueCycles = 1, latencyCycles = 5 }
  v3 = "st.v_add_f32"(v4, 1.0) { issueCycles = 1, latencyCycles = 5 }
  v6 = "st.v_fma_f32"(v0, v3, 3.0) { issueCycles = 1, latencyCycles = 5 }
  "st.buffer_store_b32"(v40, v6) { issueCycles = 1, latencyCycles = 1 }
}

#--- In-place operations: v0 redefined using itself, all live
# CHECK-LABEL: @in_place_operations
# CHECK: v_mul_f32
# CHECK: v_add_f32
# CHECK: v_sub_f32
# CHECK: buffer_store_b32

st.func @in_place_operations() {
^entry:
  v0 = "st.v_mul_f32"(v1, v2) { issueCycles = 1, latencyCycles = 5 }
  v0 = "st.v_add_f32"(v0, v3) { issueCycles = 1, latencyCycles = 5 }
  v4 = "st.v_sub_f32"(v0, v5) { issueCycles = 1, latencyCycles = 5 }
  "st.buffer_store_b32"(v40, v4) { issueCycles = 1, latencyCycles = 1 }
}