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Mail Archives: djgpp/1994/10/06/06:19:22

Date: Thu, 6 Oct 1994 09:25:23 +0200
From: gbm AT ii DOT pw DOT edu DOT pl (Grzegorz B. Mazur)
To: djgpp AT sun DOT soe DOT clarkson DOT edu
Subject: 16 vs. 32

On REAL 32 bit chips, like 386, 486 and above, and MC68020 and above
32-bit maath is at least as fast as 16-bit, assuming that the operands are
in registers or are properly aligned in memory (and memorybus is at least
32-bit wide). The above is not the case for MC68000, 68010 (16-bit memory bus
and 16 bit INTERNAL BUS!!!), and for 386SX memory references.
So  there is no reason for not using 32 bit ints for 386+. All the real
compilers do it (incl. GCC).

G.

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