https://gcc.gnu.org/bugzilla/show_bug.cgi?id=116814
--- Comment #3 from GCC Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Pan Li <pa...@gcc.gnu.org>: https://gcc.gnu.org/g:de6fe690db32689ba5e5c6f551672a19e6cae5d4 commit r15-3832-gde6fe690db32689ba5e5c6f551672a19e6cae5d4 Author: Pan Li <pan2...@intel.com> Date: Mon Sep 23 22:37:58 2024 +0800 Widening-Mul: Fix one ICE for SAT_SUB matching operand checking This patch would like to fix the following ICE for -O2 -m32 of x86_64. during RTL pass: expand JackMidiAsyncWaitQueue.cpp.cpp: In function 'void DequeueEvent(unsigned int)': JackMidiAsyncWaitQueue.cpp.cpp:3:6: internal compiler error: in expand_fn_using_insn, at internal-fn.cc:263 3 | void DequeueEvent(unsigned frame) { | ^~~~~~~~~~~~ 0x27b580d diagnostic_context::diagnostic_impl(rich_location*, diagnostic_metadata const*, diagnostic_option_id, char const*, __va_list_tag (*) [1], diagnostic_t) ???:0 0x27c4a3f internal_error(char const*, ...) ???:0 0x27b3994 fancy_abort(char const*, int, char const*) ???:0 0xf25ae5 expand_fn_using_insn(gcall*, insn_code, unsigned int, unsigned int) ???:0 0xf2a124 expand_direct_optab_fn(internal_fn, gcall*, optab_tag, unsigned int) ???:0 0xf2c87c expand_SAT_SUB(internal_fn, gcall*) ???:0 We allowed the operand convert when matching SAT_SUB in match.pd, to support the zip benchmark SAT_SUB pattern. Aka, (convert? (minus (convert1? @0) (convert1? @1))) for below sample code. void test (uint16_t *x, unsigned b, unsigned n) { unsigned a = 0; register uint16_t *p = x; do { a = *--p; *p = (uint16_t)(a >= b ? a - b : 0); // Truncate after .SAT_SUB } while (--n); } The pattern match for SAT_SUB itself may also act on below scalar sample code too. unsigned long long GetTimeFromFrames(int); unsigned long long GetMicroSeconds(); void DequeueEvent(unsigned frame) { long long frame_time = GetTimeFromFrames(frame); unsigned long long current_time = GetMicroSeconds(); DequeueEvent(frame_time < current_time ? 0 : frame_time - current_time); } Aka: uint32_t a = (uint32_t)SAT_SUB(uint64_t, uint64_t); Then there will be a problem when ia32 or -m32 is given when compiling. Because we only check the lhs (aka uint32_t) type is supported by ifn instead of the operand (aka uint64_t). Mostly DImode is disabled for 32 bits target like ia32 or rv32gcv, and then trigger ICE when expanding. The below test suites are passed for this patch. * The rv64gcv fully regression test. * The x86 bootstrap test. * The x86 fully regression test. PR middle-end/116814 gcc/ChangeLog: * tree-ssa-math-opts.cc (build_saturation_binary_arith_call): Make ifn is_supported type check based on operand instead of lhs. gcc/testsuite/ChangeLog: * g++.dg/torture/pr116814-1.C: New test. Signed-off-by: Pan Li <pan2...@intel.com>