• d-bugmail puremagic.com (27/27) Aug 02 2020 https://issues.dlang.org/show_bug.cgi?id=21101

d-bugmail puremagic.com writes:

https://issues.dlang.org/show_bug.cgi?id=21101

          Issue ID: 21101
           Summary: Inline Assembler: 32 bit values are truncated to 32
                    bits
           Product: D
           Version: D2
          Hardware: x86_64
                OS: All
            Status: NEW
          Severity: normal
          Priority: P1
         Component: dmd
          Assignee: nobody puremagic.com
          Reporter: bugzilla digitalmars.com

Bug report transferred from https://issues.dlang.org/show_bug.cgi?id=6459 :

Another negative immediate value issue:

mov             EAX,-2;                         /* line 1 */
mov             EAX,0xFFFFFFFE;                 /* line 2 */
mov             EAX,0xFFFFFFFFFFFFFFFE;         /* line 3 */
mov             R8D,-2;                         /* line 4 */
mov             R8D,0xFFFFFFFE;                 /* line 5 */
mov             R8D,0xFFFFFFFFFFFFFFFE;         /* line 6 */

Anybody writing line 3 or 6 has probably made a mistake, but line 3 is accepted
as equivalent to 1 and 2, and line 6 is accepted as equivalent to 4 and 5 (as
32 bit loads clear the top 32 bits of the equivalent 64 bit register they do
not sign extend).

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