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aeee05f53a
This is part c of relocation overflow handling. Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
79 lines
2.9 KiB
C
79 lines
2.9 KiB
C
/*
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* TCG Backend Data: load-store optimization only.
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*
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* Permission is hereby granted, free of charge, to any person obtaining a copy
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* of this software and associated documentation files (the "Software"), to deal
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* in the Software without restriction, including without limitation the rights
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* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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* copies of the Software, and to permit persons to whom the Software is
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* furnished to do so, subject to the following conditions:
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*
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* The above copyright notice and this permission notice shall be included in
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* all copies or substantial portions of the Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
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* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
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* THE SOFTWARE.
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*/
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typedef struct TCGLabelQemuLdst {
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bool is_ld; /* qemu_ld: true, qemu_st: false */
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TCGMemOpIdx oi;
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TCGType type; /* result type of a load */
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TCGReg addrlo_reg; /* reg index for low word of guest virtual addr */
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TCGReg addrhi_reg; /* reg index for high word of guest virtual addr */
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TCGReg datalo_reg; /* reg index for low word to be loaded or stored */
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TCGReg datahi_reg; /* reg index for high word to be loaded or stored */
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tcg_insn_unit *raddr; /* gen code addr of the next IR of qemu_ld/st IR */
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tcg_insn_unit *label_ptr[2]; /* label pointers to be updated */
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QSIMPLEQ_ENTRY(TCGLabelQemuLdst) next;
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} TCGLabelQemuLdst;
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/*
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* Generate TB finalization at the end of block
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*/
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static bool tcg_out_qemu_ld_slow_path(TCGContext *s, TCGLabelQemuLdst *l);
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static bool tcg_out_qemu_st_slow_path(TCGContext *s, TCGLabelQemuLdst *l);
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static int tcg_out_ldst_finalize(TCGContext *s)
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{
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TCGLabelQemuLdst *lb;
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/* qemu_ld/st slow paths */
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QSIMPLEQ_FOREACH(lb, &s->ldst_labels, next) {
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if (lb->is_ld
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? !tcg_out_qemu_ld_slow_path(s, lb)
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: !tcg_out_qemu_st_slow_path(s, lb)) {
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return -2;
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}
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/* Test for (pending) buffer overflow. The assumption is that any
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one operation beginning below the high water mark cannot overrun
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the buffer completely. Thus we can test for overflow after
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generating code without having to check during generation. */
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if (unlikely((void *)s->code_ptr > s->code_gen_highwater)) {
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return -1;
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}
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}
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return 0;
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}
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/*
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* Allocate a new TCGLabelQemuLdst entry.
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*/
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static inline TCGLabelQemuLdst *new_ldst_label(TCGContext *s)
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{
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TCGLabelQemuLdst *l = tcg_malloc(sizeof(*l));
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QSIMPLEQ_INSERT_TAIL(&s->ldst_labels, l, next);
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return l;
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}
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