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dpgeorgedpgeorge
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py/asmx64: Support moving a 64-bit immediate to one of top 8 registers.
If constants (eg mp_const_none_obj) are placed in very high memory locations that require 64-bits for the pointer then the assembler must be able to emit instructions to move such pointers to one of the top 8 registers (ie r8-r15).
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Lines changed: 3 additions & 2 deletions

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‎py/asmx64.c‎

Lines changed: 3 additions & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -344,8 +344,9 @@ STATIC void asm_x64_mov_i32_to_r64(asm_x64_t *as, int src_i32, int dest_r64) {
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void asm_x64_mov_i64_to_r64(asm_x64_t *as, int64_t src_i64, int dest_r64) {
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// cpu defaults to i32 to r64
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// to mov i64 to r64 need to use REX prefix
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assert(dest_r64 < 8);
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asm_x64_write_byte_2(as, REX_PREFIX | REX_W, OPCODE_MOV_I64_TO_R64 | dest_r64);
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asm_x64_write_byte_2(as,
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REX_PREFIX | REX_W | (dest_r64 < 8 ? 0 : REX_B),
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OPCODE_MOV_I64_TO_R64 | (dest_r64 & 7));
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asm_x64_write_word64(as, src_i64);
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}
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