diff options
Diffstat (limited to 'gitlab/issues/target_missing/host_missing/accel_TCG/2632.toml')
| -rw-r--r-- | gitlab/issues/target_missing/host_missing/accel_TCG/2632.toml | 91 |
1 files changed, 0 insertions, 91 deletions
diff --git a/gitlab/issues/target_missing/host_missing/accel_TCG/2632.toml b/gitlab/issues/target_missing/host_missing/accel_TCG/2632.toml deleted file mode 100644 index a6411e67..00000000 --- a/gitlab/issues/target_missing/host_missing/accel_TCG/2632.toml +++ /dev/null @@ -1,91 +0,0 @@ -id = 2632 -title = "tcg optimization breaking memory access ordering" -state = "opened" -created_at = "2024-10-21T10:36:01.084Z" -closed_at = "n/a" -labels = ["accel: TCG"] -url = "https://gitlab.com/qemu-project/qemu/-/issues/2632" -host-os = "Linux" -host-arch = "ppc64le" -qemu-version = "v9.0.1" -guest-os = "Bare-metal" -guest-arch = "aarch64" -description = """The following code creates register dependency between 2 loads, which forces the first load to finish before the second: -``` -movz\tw0, #0x2 -str\tw0, [x1] -ldr\tw2, [x1] -eor\tw3, w2, w2 -ldr\tw4, [x5, w3, sxtw] -``` - -While translating it to tcg IR, it keeps this dependency correctly. -But after running tcg optimizations, it optimized the tcg sequence for `eor\tw3, w2, w2` at `0000000000000144` to `mov_i64 x3,$0x0`. which then removes the dependency between the loads. - -It results in incorrect behavior on the host on a multiple threaded program""" -reproduce = """1. -2. -3.""" -additional = """``` -OP: - ld_i32 loc0,env,$0xfffffffffffffff0 - brcond_i32 loc0,$0x0,lt,$L0 - st8_i32 $0x0,env,$0xfffffffffffffff4 - - ---- 0000000000000134 0000000000000000 0000000000000000 - add_i64 x28,x28,$0x2 - - ---- 0000000000000138 0000000000000000 0000000000000000 - mov_i64 x0,$0x2 - - ---- 000000000000013c 0000000000000000 0000000000001c00 - mov_i64 loc3,x1 - mov_i64 loc4,loc3 - qemu_st_a64_i64 x0,loc4,w16+un+leul,2 - - ---- 0000000000000140 0000000000000000 0000000000001c10 - mov_i64 loc5,x1 - mov_i64 loc6,loc5 - qemu_ld_a64_i64 x2,loc6,w16+un+leul,2 - - ---- 0000000000000144 0000000000000000 0000000000000000 - and_i64 loc7,x2,$0xffffffff - xor_i64 x3,x2,loc7 - and_i64 x3,x3,$0xffffffff - - ---- 0000000000000148 0000000000000000 0000000000001c20 - mov_i64 loc9,x5 - mov_i64 loc10,x3 - ext32s_i64 loc10,loc10 - add_i64 loc9,loc9,loc10 - mov_i64 loc11,loc9 - qemu_ld_a64_i64 x4,loc11,w16+un+leul,2 - st8_i32 $0x1,env,$0xfffffffffffffff4 -``` - - -``` -OP after optimization and liveness analysis: - ld_i32 tmp0,env,$0xfffffffffffffff0 pref=0xffffffff - brcond_i32 tmp0,$0x0,lt,$L0 dead: 0 - st8_i32 $0x0,env,$0xfffffffffffffff4 dead: 0 - - ---- 0000000000000134 0000000000000000 0000000000000000 - add_i64 x28,x28,$0x2 sync: 0 dead: 0 1 pref=0xffffffff - - ---- 0000000000000138 0000000000000000 0000000000000000 - mov_i64 x0,$0x2 sync: 0 dead: 0 pref=0xffffffff - - ---- 000000000000013c 0000000000000000 0000000000001c00 - qemu_st_a64_i64 $0x2,x1,w16+un+leul,2 dead: 0 - - ---- 0000000000000140 0000000000000000 0000000000001c10 - qemu_ld_a64_i64 x2,x1,w16+un+leul,2 sync: 0 dead: 0 1 pref=0xffffffff - - ---- 0000000000000144 0000000000000000 0000000000000000 - mov_i64 x3,$0x0 sync: 0 dead: 0 1 pref=0xffffffff - - ---- 0000000000000148 0000000000000000 0000000000001c20 - qemu_ld_a64_i64 x4,x5,w16+un+leul,2 sync: 0 dead: 0 1 pref=0xffffffff - st8_i32 $0x1,env,$0xfffffffffffffff4 dead: 0 -```""" |