Simplify the logic for two-part, 32-bit pc-relative addresses. Rather than assume all such fit in int32_t, do some arithmetic and assert a result, do some arithmetic first and then check to see if the pieces are in range.
Reported-by: Song Gao <gaos...@loongson.cn> Signed-off-by: Richard Henderson <richard.hender...@linaro.org> --- Hi Song. I was not thrilled by the "goto out" that you introduced in 20240618125044.687443-1-gaos...@loongson.cn Instead, I copied the logic from tcg/aarch64/ for adrp+add. r~ --- tcg/loongarch64/tcg-target.c.inc | 32 +++++++++++++++----------------- 1 file changed, 15 insertions(+), 17 deletions(-) diff --git a/tcg/loongarch64/tcg-target.c.inc b/tcg/loongarch64/tcg-target.c.inc index 7ca52d0248..e915e97bba 100644 --- a/tcg/loongarch64/tcg-target.c.inc +++ b/tcg/loongarch64/tcg-target.c.inc @@ -382,8 +382,7 @@ static void tcg_out_movi(TCGContext *s, TCGType type, TCGReg rd, * back to the slow path. */ - intptr_t pc_offset; - tcg_target_long val_lo, val_hi, pc_hi, offset_hi; + intptr_t src_rx, pc_offset; tcg_target_long hi12, hi32, hi52; /* Value fits in signed i32. */ @@ -393,24 +392,23 @@ static void tcg_out_movi(TCGContext *s, TCGType type, TCGReg rd, } /* PC-relative cases. */ - pc_offset = tcg_pcrel_diff(s, (void *)val); - if (pc_offset == sextreg(pc_offset, 0, 22) && (pc_offset & 3) == 0) { - /* Single pcaddu2i. */ - tcg_out_opc_pcaddu2i(s, rd, pc_offset >> 2); - return; + src_rx = (intptr_t)tcg_splitwx_to_rx(s->code_ptr); + if ((val & 3) == 0) { + pc_offset = val - src_rx; + if (pc_offset == sextreg(pc_offset, 0, 22)) { + /* Single pcaddu2i. */ + tcg_out_opc_pcaddu2i(s, rd, pc_offset >> 2); + return; + } } - if (pc_offset == (int32_t)pc_offset) { - /* Offset within 32 bits; load with pcalau12i + ori. */ - val_lo = sextreg(val, 0, 12); - val_hi = val >> 12; - pc_hi = (val - pc_offset) >> 12; - offset_hi = val_hi - pc_hi; - - tcg_debug_assert(offset_hi == sextreg(offset_hi, 0, 20)); - tcg_out_opc_pcalau12i(s, rd, offset_hi); + pc_offset = (val >> 12) - (src_rx >> 12); + if (pc_offset == sextreg(pc_offset, 0, 20)) { + /* Load with pcalau12i + ori. */ + tcg_target_long val_lo = val & 0xfff; + tcg_out_opc_pcalau12i(s, rd, pc_offset); if (val_lo != 0) { - tcg_out_opc_ori(s, rd, rd, val_lo & 0xfff); + tcg_out_opc_ori(s, rd, rd, val_lo); } return; } -- 2.34.1