[Fix][Codegen] Avoid extraneous parentheses in if_then_else generated code - #20285
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fengz72 wants to merge 1 commit into
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[Fix][Codegen] Avoid extraneous parentheses in if_then_else generated code#20285fengz72 wants to merge 1 commit into
fengz72 wants to merge 1 commit into
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… code The if_then_else builtin call is expanded into an if/else statement, and the condition string is wrapped in another pair of parentheses even when it is already parenthesized, e.g. `if ((i == 0))`. This triggers clang's -Wparentheses-equality warning on the generated code. Reuse the same leading/trailing parenthesis check as the IfThenElseNode handling so the redundant parentheses are not emitted. Add a regression test asserting the generated C source contains no `if ((` and the runtime result stays correct.
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Problem
Since #16242, the
if_then_elsebuiltin call is expanded into an if/else statement. When printing the condition, the codegen wraps it in another pair of parentheses even though it is already parenthesized, producingif ((i == 0)).Impact
The doubled parentheses trigger clang's
-Wparentheses-equalitywarning under-Wall/-Wparentheses, which is noisy for downstream users who compile TVM-generated C sources with strict warning settings. Correctness is not affected — the issue is cosmetic.Solution
Reuse the same leading/trailing parenthesis check as the existing
IfThenElseNodehandling inCodeGenC, so a condition that already starts and ends with parentheses is printed as-is. The generated code now readsif (i == 0).Since
CodeGenCis the shared base of all C-style backends (CUDA, Metal, ROCm, Vulkan, WebGPU, Hexagon), this fix covers them all at once.Testing
test_if_then_else_avoids_extraneous_parenthesesintests/python/codegen/test_target_codegen_c_host.py, which asserts the generated C source contains noif ((and validates the runtime result.test_target_codegen_c_host.pysuite on aarch64 Linux with a local build: 10/10 passed.pre-commit(clang-format, ruff-check, ruff-format) passed on the changed files.