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Remove experimental hunk that wasn't supposed to be checked in.
From-SVN: r30298
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5949bdae94
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8f65050e41
21
gcc/cse.c
21
gcc/cse.c
@ -5517,32 +5517,11 @@ cse_insn (insn, libcall_insn)
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&& GET_CODE (XEXP (XEXP (src_const, 0), 0)) == LABEL_REF
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&& GET_CODE (XEXP (XEXP (src_const, 0), 1)) == LABEL_REF))
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{
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rtx simplified_src_const;
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tem = find_reg_note (insn, REG_EQUAL, NULL_RTX);
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/* Make sure that the rtx is not shared with any other insn. */
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src_const = copy_rtx (src_const);
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/* Try to simplify SRC_CONST.
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The primary purpose behind simplifying the note is to allow
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for easier removal of library call sequences later. Consider
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a udiv libcall where we can determine the second argument is
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a constant. SRC_CONST would look like:
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(udiv (reg) (const_int 2**n))
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That RTL expression will simplify into:
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(lshiftrt (reg) (const_int n))
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A target using library calls for division is more likely to
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have a lshiftrt insn. Thus, it is more likely that the libcall
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can be deleted in delete_trivially_dead_insns if we simplify
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the note. */
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simplified_src_const = simplify_rtx (src_const);
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src_const = simplified_src_const ? simplified_src_const : src_const;
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/* Record the actual constant value in a REG_EQUAL note, making
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a new one if one does not already exist. */
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if (tem)
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