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GPU/Shader Instruction Set: Difference between revisions

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Smea (talk | contribs)
373 edits
i0-i7 used for LOOP
Smea (talk | contribs)
373 edits
CMP
Line 70: Line 70:
|  0x1A
|  0x1A
|  0x6
|  0x6
|  Opcode
|}
Format 1c : (used for comparison instructions)
{| class="wikitable" border="1"
|-
!  Offset
!  Size (bits)
!  Description
|-
|  0x0
|  0x7
|  Operand descriptor ID (DESC)
|-
|  0x7
|  0x7
|  Source 1 register (SRC1)
|-
|  0xE
|  0x5
|  Source 2 register (SRC2)
|-
|  0x13
|  0x2
|  Address register index (IDX)
|-
|  0x15
|  0x3
|  Comparison operator for Y (CMPY)
|-
|  0x18
|  0x3
|  Comparison operator for X (CMPX)
|-
|  0x1B
|  0x5
|  Opcode
|  Opcode
|}
|}
Line 265: Line 301:
|  0x28
|  0x28
|  2
|  2
|  IF?
|  IF
|  If condition (don't know how condition flags work yet) is true, then executes instructions until DST, then jumps to DST+NUM; else, jumps to DST
|  If condition (don't know how condition flags work yet, based on cmp.x and cmp.y booleans set by CMP) is true, then executes instructions until DST, then jumps to DST+NUM; else, jumps to DST
|-
|-
|  0x29
|  0x29
Line 288: Line 324:
|  Jumps to DST if condition (don't know how condition flags work yet) is true, else does nothing.
|  Jumps to DST if condition (don't know how condition flags work yet) is true, else does nothing.
|-
|-
|  0x2E
|  0x2E-0x2F
|  1
|  1c
|  CMP1
|  CMP
|  Presumably compares two vectors component by component and sets the appropriate flags. (unknown exactly how this works as of yet)
|  Sets booleans cmp.x and cmp.y based on the operand's x and y components and the CMPX and CMPY comparison operators respectively.
|-
|  0x2F
|  1
|  CMP2
|  Presumably compares two vectors component by component and sets the appropriate flags. (unknown exactly how this works as of yet)
|-
|-
|  0x38-0x3F
|  0x38-0x3F
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