ADSP-2126x SHARC Processor Hardware Reference
2-53
Processing Elements
SIMD conditional instructions with the same destination registers
do not produce predictable transfers. For example, the instruction
IF EQ R4 = R14 — R15, S4 = R6;
may not work as expected. This
kind of usage is prohibited, as it is not logical to use it this way.
Table 2-17. Register-to-Register Move Summary (SISD Versus SIMD)
Mode
Instruction
Explicit Transfer
Executed According
to PEx
Implicit Transfer
Executed According
to PEx
SISD
1
IF condition compute, Rx = Ry;
Rx loaded from Ry
None
IF condition compute, Rx = Sy;
Rx loaded from Sy
None
IF condition compute, Sx = Ry;
Sx loaded from Ry
None
IF condition compute, Sx = Sy;
Sx loaded from Sy
None
IF condition compute, Rx <-> Sy;
Rx loaded from Sy
Sy loaded from Rx
SIMD
2
IF condition compute, Rx = Ry;
Rx loaded from Ry
Sx loaded from Sy
IF condition compute, Rx = Sy;
Rx loaded from Sy
Sx loaded from Ry
IF condition compute, Sx = Ry;
Sx loaded from Ry
Rx loaded from Sy
IF condition compute, Sx = Sy;
Sx loaded from Sy
Rx loaded from Ry
IF condition compute, Rx <-> Sy;
3
Rx loaded from Sy
Sy loaded from Rx
1 In SISD mode, the conditional applies only to the entire operation and is only tested against PEx’s
flags. When the condition tests true, the entire operation occurs.
2 In SIMD mode, the conditional applies separately to the explicit and implicit transfers. Where the
condition tests true (PEx for the explicit and PEy for the implicit), the operation occurs in that pro-
cessing element.
3 Register-to-register transfers (R0=S0) and register swaps (R0<->S0) do not cause a PMD bus conflict.
These operations use only the DMD bus and a hidden 16-bit bus to perform the two register moves.
Содержание ADSP-21261 SHARC
Страница 30: ...Contents xxx ADSP 2126x SHARC Processor Hardware Reference ...
Страница 40: ...Register Diagram Conventions xl ADSP 2126x SHARC Processor Hardware Reference ...
Страница 58: ...Differences From Previous SHARCs 1 18 ADSP 2126x SHARC Processor Hardware Reference ...
Страница 112: ...Secondary Processing Element PEy 2 54 ADSP 2126x SHARC Processor Hardware Reference ...
Страница 178: ...Summary 3 66 ADSP 2126x SHARC Processor Hardware Reference ...
Страница 204: ...DAG Instruction Summary 4 26 ADSP 2126x SHARC Processor Hardware Reference ...
Страница 322: ...Setting Up DMA 7 32 ADSP 2126x SHARC Processor Hardware Reference ...
Страница 436: ...SPORT Programming Examples 9 86 ADSP 2126x SHARC Processor Hardware Reference ...
Страница 521: ...ADSP 2126x SHARC Processor Hardware Reference 11 31 Input Data Port rts IDP_ISR end ...
Страница 522: ...Input Data Port Programming Example 11 32 ADSP 2126x SHARC Processor Hardware Reference ...
Страница 590: ...Timer Programming Examples 14 20 ADSP 2126x SHARC Processor Hardware Reference ...
Страница 796: ...I O Processor Registers A 174 ADSP 2126x SHARC Processor Hardware Reference ...
Страница 800: ...B 4 ADSP 2126x SHARC Processor Core Manual ...
Страница 846: ...Index I 36 ADSP 2126x SHARC Processor Hardware Reference ...