https://gcc.gnu.org/g:f2586a4a6c8ae21775fecb57f46ddbaa83af49f3
commit r16-4170-gf2586a4a6c8ae21775fecb57f46ddbaa83af49f3 Author: Andreas Schwab <[email protected]> Date: Mon Sep 29 18:46:45 2025 +0200 m68k: fix adddi3/subdi3 with POST_INC/PRE_DEC destination This part has never been exercised until r15-1579-g792f97b44ffc5e. PR target/122066 * config/m68k/m68k.md (adddi3, subdi3): Strip POST_INC and PRE_DEC when generating high part of the destination operand. * gcc.c-torture/compile/pr122066.c: New test. Diff: --- gcc/config/m68k/m68k.md | 16 +++++++++------- gcc/testsuite/gcc.c-torture/compile/pr122066.c | 18 ++++++++++++++++++ 2 files changed, 27 insertions(+), 7 deletions(-) diff --git a/gcc/config/m68k/m68k.md b/gcc/config/m68k/m68k.md index c96937f0b2ca..7f345bfa123b 100644 --- a/gcc/config/m68k/m68k.md +++ b/gcc/config/m68k/m68k.md @@ -2442,14 +2442,15 @@ gcc_assert (GET_CODE (operands[0]) == MEM); if (GET_CODE (XEXP (operands[0], 0)) == POST_INC) { - operands[1] = gen_rtx_MEM (SImode, - plus_constant (Pmode, - XEXP(operands[0], 0), -8)); + operands[1] + = gen_rtx_MEM (SImode, + plus_constant (Pmode, + XEXP (XEXP (operands[0], 0), 0), -8)); return "move%.l %0,%3\;add%.l %R2,%0\;addx%.l %2,%3\;move%.l %3,%1"; } else if (GET_CODE (XEXP (operands[0], 0)) == PRE_DEC) { - operands[1] = XEXP(operands[0], 0); + operands[1] = XEXP (XEXP (operands[0], 0), 0); return "add%.l %R2,%0\;move%.l %0,%3\;addx%.l %2,%3\;move%.l %3,%1"; } else @@ -2949,13 +2950,14 @@ if (GET_CODE (XEXP (operands[0], 0)) == POST_INC) { operands[1] - = gen_rtx_MEM (SImode, plus_constant (Pmode, - XEXP (operands[0], 0), -8)); + = gen_rtx_MEM (SImode, + plus_constant (Pmode, + XEXP (XEXP (operands[0], 0), 0), -8)); return "move%.l %0,%3\;sub%.l %R2,%0\;subx%.l %2,%3\;move%.l %3,%1"; } else if (GET_CODE (XEXP (operands[0], 0)) == PRE_DEC) { - operands[1] = XEXP(operands[0], 0); + operands[1] = XEXP (XEXP (operands[0], 0), 0); return "sub%.l %R2,%0\;move%.l %0,%3\;subx%.l %2,%3\;move%.l %3,%1"; } else diff --git a/gcc/testsuite/gcc.c-torture/compile/pr122066.c b/gcc/testsuite/gcc.c-torture/compile/pr122066.c new file mode 100644 index 000000000000..5fecb7f02b8a --- /dev/null +++ b/gcc/testsuite/gcc.c-torture/compile/pr122066.c @@ -0,0 +1,18 @@ +/* PR target/122066 -- adddi3/subdi3 mishandle POST_INC/PRE_DEC dest on m68k */ + +struct { + long long wp_ssd[3]; + long long wp_sum[3]; +} m_lowres; +void calcAdaptiveQuantFrame() { + for (int i = 0; i < 3; i++) { + long sum = m_lowres.wp_sum[i]; + long long ssd = m_lowres.wp_ssd[i]; + m_lowres.wp_ssd[i] = ssd - sum; + } + for (int i = 0; i < 3; i++) { + long sum = m_lowres.wp_sum[i]; + long long ssd = m_lowres.wp_ssd[i]; + m_lowres.wp_ssd[i] = ssd + sum; + } +}
