From d5132903518fadad579ef2de9e45fce98eefaa63 Mon Sep 17 00:00:00 2001 From: Richard Henderson Date: Fri, 30 Nov 2018 21:25:13 +0000 Subject: [PATCH] tcg/ppc: Return false on failure from patch_reloc MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit The reloc_pc{14,24}_val routines retain their asserts. Use these directly within the slow paths. Reviewed-by: Alex Bennée Signed-off-by: Richard Henderson --- tcg/ppc/tcg-target.inc.c | 32 +++++++++++++++++++++----------- 1 file changed, 21 insertions(+), 11 deletions(-) diff --git a/tcg/ppc/tcg-target.inc.c b/tcg/ppc/tcg-target.inc.c index 860b0d36e1..8c1cfdd7ac 100644 --- a/tcg/ppc/tcg-target.inc.c +++ b/tcg/ppc/tcg-target.inc.c @@ -193,9 +193,14 @@ static uint32_t reloc_pc24_val(tcg_insn_unit *pc, tcg_insn_unit *target) return disp & 0x3fffffc; } -static void reloc_pc24(tcg_insn_unit *pc, tcg_insn_unit *target) +static bool reloc_pc24(tcg_insn_unit *pc, tcg_insn_unit *target) { - *pc = (*pc & ~0x3fffffc) | reloc_pc24_val(pc, target); + ptrdiff_t disp = tcg_ptr_byte_diff(target, pc); + if (in_range_b(disp)) { + *pc = (*pc & ~0x3fffffc) | (disp & 0x3fffffc); + return true; + } + return false; } static uint16_t reloc_pc14_val(tcg_insn_unit *pc, tcg_insn_unit *target) @@ -205,9 +210,14 @@ static uint16_t reloc_pc14_val(tcg_insn_unit *pc, tcg_insn_unit *target) return disp & 0xfffc; } -static void reloc_pc14(tcg_insn_unit *pc, tcg_insn_unit *target) +static bool reloc_pc14(tcg_insn_unit *pc, tcg_insn_unit *target) { - *pc = (*pc & ~0xfffc) | reloc_pc14_val(pc, target); + ptrdiff_t disp = tcg_ptr_byte_diff(target, pc); + if (disp == (int16_t) disp) { + *pc = (*pc & ~0xfffc) | (disp & 0xfffc); + return true; + } + return false; } /* parse target specific constraints */ @@ -524,11 +534,9 @@ static bool patch_reloc(tcg_insn_unit *code_ptr, int type, switch (type) { case R_PPC_REL14: - reloc_pc14(code_ptr, target); - break; + return reloc_pc14(code_ptr, target); case R_PPC_REL24: - reloc_pc24(code_ptr, target); - break; + return reloc_pc24(code_ptr, target); case R_PPC_ADDR16: /* We are abusing this relocation type. This points to a pair of insns, addis + load. If the displacement is small, we @@ -540,7 +548,9 @@ static bool patch_reloc(tcg_insn_unit *code_ptr, int type, } else { int16_t lo = value; int hi = value - lo; - assert(hi + lo == value); + if (hi + lo != value) { + return false; + } code_ptr[0] = deposit32(code_ptr[0], 0, 16, hi >> 16); code_ptr[1] = deposit32(code_ptr[1], 0, 16, lo); } @@ -1638,7 +1648,7 @@ static void tcg_out_qemu_ld_slow_path(TCGContext *s, TCGLabelQemuLdst *lb) TCGMemOp opc = get_memop(oi); TCGReg hi, lo, arg = TCG_REG_R3; - reloc_pc14(lb->label_ptr[0], s->code_ptr); + **lb->label_ptr |= reloc_pc14_val(*lb->label_ptr, s->code_ptr); tcg_out_mov(s, TCG_TYPE_PTR, arg++, TCG_AREG0); @@ -1683,7 +1693,7 @@ static void tcg_out_qemu_st_slow_path(TCGContext *s, TCGLabelQemuLdst *lb) TCGMemOp s_bits = opc & MO_SIZE; TCGReg hi, lo, arg = TCG_REG_R3; - reloc_pc14(lb->label_ptr[0], s->code_ptr); + **lb->label_ptr |= reloc_pc14_val(*lb->label_ptr, s->code_ptr); tcg_out_mov(s, TCG_TYPE_PTR, arg++, TCG_AREG0); -- 2.11.0