[all-commits] [llvm/llvm-project] 6a58ab: [ExpandVariadics] Don't lower unmangled C printf o...

[Paulius Velesko via All-commits]

  Branch: refs/heads/release/23.x
  Home:   https://github.com/llvm/llvm-project
  Commit: 6a58ab22a4d41277277f50e16d3b235c9d9010a6
      https://github.com/llvm/llvm-project/commit/6a58ab22a4d41277277f50e16d3b235c9d9010a6
  Author: Paulius Velesko <pvelesko at pglc.io>
  Date:   2026-08-05 (Wed, 05 Aug 2026)

  Changed paths:
    M llvm/lib/Transforms/IPO/ExpandVariadics.cpp
    A llvm/test/Transforms/ExpandVariadics/spirv-printf.ll

  Log Message:
  -----------
  [ExpandVariadics] Don't lower unmangled C printf on SPIR-V (#206998)

An unmangled C `printf` declaration demangles to bare `printf` (no
argument list), so `SPIRV::ignoreFunction`'s `printf(` prefix check
missed it and ExpandVariadics packed its arguments into a vararg buffer;
the SPIR-V backend then passed the buffer pointer as printf's first
variadic operand, so device printf printed pointer values instead of the
actual arguments. Match the bare name too so OpenCL/HIP printf (emitted
unmangled) is left as a variadic call for the backend's OpenCL.std
printf lowering.

(cherry picked from commit b1d21c6d3121898dc13c0df8cf9e4410bee75cfb)



To unsubscribe from these emails, change your notification settings at https://github.com/llvm/llvm-project/settings/notifications