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Fix AOT shift operations for indirect constants (#2627)

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When doing more investigations related to this PR:
  https://github.com/bytecodealliance/wasm-micro-runtime/pull/2619
We found that in some scenarios the constant might not be directly
available to the LLVM IR builder, e.g.:
```
  (func $const_ret (result i32)
    i32.const -5
  )
  (func $foo
    (i32.shr_u (i32.const -1) (call $const_ret))
    (i32.const 31)
  )
```
In that case, the right parameter to `i32.shr_u` is not constant, therefore
the `SHIFT_COUNT_MASK` isn't applied. However, when the optimization
is enabled (`--opt-level` is 2 or 3), the optimization passes resolve the
call into constant, and that constant is poisoned, causing the compiler to
resolve the whole function to an exception.
This commit is contained in:
Marcin Kolny
2023-10-11 04:22:34 +01:00
committed by GitHub
parent e73993709e
commit 72b34eaf30
2 changed files with 39 additions and 16 deletions
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37
tests/wamr-compiler/test_shift_negative_constants.wat
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@ -7,6 +7,7 @@
;; any problems. See: https://github.com/bytecodealliance/wasm-micro-runtime/pull/2619
(module
(memory (export "memory") 1 1)
(func $assert_eq (param i32 i32)
(i32.ne (local.get 0) (local.get 1))
if
@ -23,7 +24,7 @@
(func $i32_shr_s
(call $assert_eq
(i32.shr_u (i32.const 32) (i32.const -30))
(i32.shr_s (i32.const 32) (i32.const -30))
(i32.const 8)
)
)
@ -35,9 +36,43 @@
)
)
(func $const_ret (result i32)
i32.const -5
)
;; *_func_call tests validate the potential LLVM optimizations
;; where the right parameter of the shift operation is an
;; indirect constant value.
(func $i32_shr_u_func_call
(call $assert_eq
(i32.shr_u (i32.const -1) (call $const_ret))
(i32.const 31)
)
)
(func $i32_shr_s_func_call
(call $assert_eq
(i32.shr_s
(i32.const 1073741824) ;; 2^30
(call $const_ret)
)
(i32.const 8)
)
)
(func $i32_shl_func_call
(call $assert_eq
(i32.shl (i32.const -1) (call $const_ret))
(i32.const -134217728)
)
)
(func (export "_start")
call $i32_shr_u
call $i32_shr_s
call $i32_shl
call $i32_shr_u_func_call
call $i32_shr_s_func_call
call $i32_shl_func_call
)
)