[Mesa-dev] [PATCH 07/19] tgsi: add BALLOT/READ_* opcodes

Nicolai Hähnle nhaehnle at gmail.com
Fri Mar 31 17:14:07 UTC 2017


From: Ilia Mirkin <imirkin at alum.mit.edu>

v2 (Nicolai):
- BALLOT isn't per-channel
- expand the documentation (also for VOTE_*)

Signed-off-by: Ilia Mirkin <imirkin at alum.mit.edu>
Signed-off-by: Nicolai Hähnle <nicolai.haehnle at amd.com>
---
 src/gallium/auxiliary/tgsi/tgsi_info.c     |  6 +--
 src/gallium/docs/source/tgsi.rst           | 67 +++++++++++++++++++++++++-----
 src/gallium/include/pipe/p_shader_tokens.h |  6 +--
 3 files changed, 62 insertions(+), 17 deletions(-)

diff --git a/src/gallium/auxiliary/tgsi/tgsi_info.c b/src/gallium/auxiliary/tgsi/tgsi_info.c
index 5a6a9bc..30bad6d 100644
--- a/src/gallium/auxiliary/tgsi/tgsi_info.c
+++ b/src/gallium/auxiliary/tgsi/tgsi_info.c
@@ -106,51 +106,51 @@ static const struct tgsi_opcode_info opcode_info[TGSI_OPCODE_LAST] =
    { 1, 3, 0, 0, 0, 0, 0, COMP, "CMP", TGSI_OPCODE_CMP },
    { 1, 1, 0, 0, 0, 0, 0, CHAN, "SCS", TGSI_OPCODE_SCS },
    { 1, 2, 1, 0, 0, 0, 0, OTHR, "TXB", TGSI_OPCODE_TXB },
    { 1, 1, 0, 0, 0, 0, 0, OTHR, "FBFETCH", TGSI_OPCODE_FBFETCH },
    { 1, 2, 0, 0, 0, 0, 0, COMP, "DIV", TGSI_OPCODE_DIV },
    { 1, 2, 0, 0, 0, 0, 0, REPL, "DP2", TGSI_OPCODE_DP2 },
    { 1, 2, 1, 0, 0, 0, 0, OTHR, "TXL", TGSI_OPCODE_TXL },
    { 0, 0, 0, 0, 0, 0, 0, NONE, "BRK", TGSI_OPCODE_BRK },
    { 0, 1, 0, 0, 1, 0, 1, NONE, "IF", TGSI_OPCODE_IF },
    { 0, 1, 0, 0, 1, 0, 1, NONE, "UIF", TGSI_OPCODE_UIF },
-   { 0, 1, 0, 0, 0, 0, 1, NONE, "", 76 },      /* removed */
+   { 1, 2, 0, 0, 0, 0, 0, COMP, "READ_INVOC", TGSI_OPCODE_READ_INVOC },
    { 0, 0, 0, 0, 1, 1, 1, NONE, "ELSE", TGSI_OPCODE_ELSE },
    { 0, 0, 0, 0, 0, 1, 0, NONE, "ENDIF", TGSI_OPCODE_ENDIF },
    { 1, 1, 0, 0, 0, 0, 0, COMP, "DDX_FINE", TGSI_OPCODE_DDX_FINE },
    { 1, 1, 0, 0, 0, 0, 0, COMP, "DDY_FINE", TGSI_OPCODE_DDY_FINE },
    { 0, 1, 0, 0, 0, 0, 0, NONE, "PUSHA", TGSI_OPCODE_PUSHA },
    { 1, 0, 0, 0, 0, 0, 0, NONE, "POPA", TGSI_OPCODE_POPA },
    { 1, 1, 0, 0, 0, 0, 0, COMP, "CEIL", TGSI_OPCODE_CEIL },
    { 1, 1, 0, 0, 0, 0, 0, COMP, "I2F", TGSI_OPCODE_I2F },
    { 1, 1, 0, 0, 0, 0, 0, COMP, "NOT", TGSI_OPCODE_NOT },
    { 1, 1, 0, 0, 0, 0, 0, COMP, "TRUNC", TGSI_OPCODE_TRUNC },
    { 1, 2, 0, 0, 0, 0, 0, COMP, "SHL", TGSI_OPCODE_SHL },
-   { 0, 0, 0, 0, 0, 0, 0, NONE, "", 88 },      /* removed */
+   { 1, 1, 0, 0, 0, 0, 0, OTHR, "BALLOT", TGSI_OPCODE_BALLOT },
    { 1, 2, 0, 0, 0, 0, 0, COMP, "AND", TGSI_OPCODE_AND },
    { 1, 2, 0, 0, 0, 0, 0, COMP, "OR", TGSI_OPCODE_OR },
    { 1, 2, 0, 0, 0, 0, 0, COMP, "MOD", TGSI_OPCODE_MOD },
    { 1, 2, 0, 0, 0, 0, 0, COMP, "XOR", TGSI_OPCODE_XOR },
    { 1, 3, 0, 0, 0, 0, 0, COMP, "SAD", TGSI_OPCODE_SAD },
    { 1, 2, 1, 0, 0, 0, 0, OTHR, "TXF", TGSI_OPCODE_TXF },
    { 1, 2, 1, 0, 0, 0, 0, OTHR, "TXQ", TGSI_OPCODE_TXQ },
    { 0, 0, 0, 0, 0, 0, 0, NONE, "CONT", TGSI_OPCODE_CONT },
    { 0, 1, 0, 0, 0, 0, 0, NONE, "EMIT", TGSI_OPCODE_EMIT },
    { 0, 1, 0, 0, 0, 0, 0, NONE, "ENDPRIM", TGSI_OPCODE_ENDPRIM },
    { 0, 0, 0, 0, 1, 0, 1, NONE, "BGNLOOP", TGSI_OPCODE_BGNLOOP },
    { 0, 0, 0, 0, 0, 0, 1, NONE, "BGNSUB", TGSI_OPCODE_BGNSUB },
    { 0, 0, 0, 0, 1, 1, 0, NONE, "ENDLOOP", TGSI_OPCODE_ENDLOOP },
    { 0, 0, 0, 0, 0, 1, 0, NONE, "ENDSUB", TGSI_OPCODE_ENDSUB },
    { 1, 1, 1, 0, 0, 0, 0, OTHR, "TXQ_LZ", TGSI_OPCODE_TXQ_LZ },
    { 1, 1, 1, 0, 0, 0, 0, OTHR, "TXQS", TGSI_OPCODE_TXQS },
    { 1, 1, 0, 0, 0, 0, 0, OTHR, "RESQ", TGSI_OPCODE_RESQ },
-   { 0, 0, 0, 0, 0, 0, 0, NONE, "", 106 },     /* removed */
+   { 1, 1, 0, 0, 0, 0, 0, COMP, "READ_FIRST", TGSI_OPCODE_READ_FIRST },
    { 0, 0, 0, 0, 0, 0, 0, NONE, "NOP", TGSI_OPCODE_NOP },
    { 1, 2, 0, 0, 0, 0, 0, COMP, "FSEQ", TGSI_OPCODE_FSEQ },
    { 1, 2, 0, 0, 0, 0, 0, COMP, "FSGE", TGSI_OPCODE_FSGE },
    { 1, 2, 0, 0, 0, 0, 0, COMP, "FSLT", TGSI_OPCODE_FSLT },
    { 1, 2, 0, 0, 0, 0, 0, COMP, "FSNE", TGSI_OPCODE_FSNE },
    { 0, 1, 0, 0, 0, 0, 0, OTHR, "MEMBAR", TGSI_OPCODE_MEMBAR },
    { 0, 1, 0, 0, 0, 0, 0, NONE, "CALLNZ", TGSI_OPCODE_CALLNZ },
    { 0, 1, 0, 0, 0, 0, 0, NONE, "", 114 },     /* removed */
    { 0, 1, 0, 0, 0, 0, 0, NONE, "BREAKC", TGSI_OPCODE_BREAKC },
    { 0, 1, 0, 0, 0, 0, 0, NONE, "KILL_IF", TGSI_OPCODE_KILL_IF },
diff --git a/src/gallium/docs/source/tgsi.rst b/src/gallium/docs/source/tgsi.rst
index 05b06ce..7e9b47c 100644
--- a/src/gallium/docs/source/tgsi.rst
+++ b/src/gallium/docs/source/tgsi.rst
@@ -2852,36 +2852,81 @@ only be used with 32-bit integer image formats.
 
   The following operation is performed atomically:
 
 .. math::
 
   dst_x = resource[offset]
 
   resource[offset] = (dst_x > src_x ? dst_x : src_x)
 
 
-.. _voteopcodes:
+.. _interlaneopcodes:
+
+Inter-lane opcodes
+^^^^^^^^^^^^^^^^^^
+
+These opcodes reduce the given value across the shader invocations
+running in the current SIMD group. For all but the READ_INVOC operations,
+every thread in the subgroup will receive the same result. The VOTE_* and
+BALLOT operations accept a single-channel argument that is treated as a
+boolean and produce a 64-bit value.
+
+.. opcode:: VOTE_ANY - Value is set in any of the active invocations
+
+  Syntax: ``VOTE_ANY dst, value``
+
+  Example: ``VOTE_ANY TEMP[0].xy, TEMP[1].x``
+
+
+.. opcode:: VOTE_ALL - Value is set in all of the active invocations
+
+  Syntax: ``VOTE_ALL dst, value``
+
+  Example: ``VOTE_ALL TEMP[0].xy, TEMP[1].x``
+
+
+.. opcode:: VOTE_EQ - Value is the same in all of the active invocations
+
+  Syntax: ``VOTE_EQ dst, value``
+
+  Example: ``VOTE_EQ TEMP[0].xy, TEMP[1].x``
+
+
+.. opcode:: BALLOT - Lanemask of whether the value is set in each active
+            invocation
+
+  Syntax: ``BALLOT dst, value``
+
+  Example: ``BALLOT TEMP[0].xy, TEMP[1].x``
+
+  When the argument is a constant true, this produces a bitmask of active
+  invocations. In fragment shaders, this can include helper invocations
+  (invocations whose outputs and writes to memory are discarded, but which
+  are used to compute derivatives).
+
+
+.. opcode:: READ_FIRST - Broadcast the value from the first active
+            invocation to all active lanes
+
+  Syntax: ``READ_FIRST dst, value``
+
+  Example: ``READ_FIRST TEMP[0], TEMP[1]``
 
-Vote opcodes
-^^^^^^^^^^^^
 
-These opcodes compare the given value across the shader invocations
-running in the current SIMD group. The details of exactly which
-invocations get compared are implementation-defined, and it would be a
-correct implementation to only ever consider the current thread's
-value. (i.e. SIMD group of 1). The argument is treated as a boolean.
+.. opcode:: READ_INVOC - Retrieve the value from the given invocation
+            (need not be uniform)
 
-.. opcode:: VOTE_ANY - Value is set in any of the current invocations
+  Syntax: ``READ_INVOC dst, value, invocation``
 
-.. opcode:: VOTE_ALL - Value is set in all of the current invocations
+  Example: ``READ_INVOC TEMP[0].xy, TEMP[1].xy, TEMP[2].x``
 
-.. opcode:: VOTE_EQ - Value is the same in all of the current invocations
+  invocation.x controls the invocation number to read from for all channels.
 
 
 Explanation of symbols used
 ------------------------------
 
 
 Functions
 ^^^^^^^^^^^^^^
 
 
diff --git a/src/gallium/include/pipe/p_shader_tokens.h b/src/gallium/include/pipe/p_shader_tokens.h
index 8c08f27..d461f78 100644
--- a/src/gallium/include/pipe/p_shader_tokens.h
+++ b/src/gallium/include/pipe/p_shader_tokens.h
@@ -398,53 +398,53 @@ struct tgsi_property_data {
 #define TGSI_OPCODE_CMP                 66
 #define TGSI_OPCODE_SCS                 67
 #define TGSI_OPCODE_TXB                 68
 #define TGSI_OPCODE_FBFETCH             69
 #define TGSI_OPCODE_DIV                 70
 #define TGSI_OPCODE_DP2                 71
 #define TGSI_OPCODE_TXL                 72
 #define TGSI_OPCODE_BRK                 73
 #define TGSI_OPCODE_IF                  74
 #define TGSI_OPCODE_UIF                 75
-                                /* gap */
+#define TGSI_OPCODE_READ_INVOC          76
 #define TGSI_OPCODE_ELSE                77
 #define TGSI_OPCODE_ENDIF               78
 
 #define TGSI_OPCODE_DDX_FINE            79
 #define TGSI_OPCODE_DDY_FINE            80
 
 #define TGSI_OPCODE_PUSHA               81
 #define TGSI_OPCODE_POPA                82
 #define TGSI_OPCODE_CEIL                83
 #define TGSI_OPCODE_I2F                 84
 #define TGSI_OPCODE_NOT                 85
 #define TGSI_OPCODE_TRUNC               86
 #define TGSI_OPCODE_SHL                 87
-                                /* gap */
+#define TGSI_OPCODE_BALLOT              88
 #define TGSI_OPCODE_AND                 89
 #define TGSI_OPCODE_OR                  90
 #define TGSI_OPCODE_MOD                 91
 #define TGSI_OPCODE_XOR                 92
 #define TGSI_OPCODE_SAD                 93
 #define TGSI_OPCODE_TXF                 94
 #define TGSI_OPCODE_TXQ                 95
 #define TGSI_OPCODE_CONT                96
 #define TGSI_OPCODE_EMIT                97
 #define TGSI_OPCODE_ENDPRIM             98
 #define TGSI_OPCODE_BGNLOOP             99
 #define TGSI_OPCODE_BGNSUB              100
 #define TGSI_OPCODE_ENDLOOP             101
 #define TGSI_OPCODE_ENDSUB              102
 #define TGSI_OPCODE_TXQ_LZ              103 /* TXQ for mipmap level 0 */
 #define TGSI_OPCODE_TXQS                104
 #define TGSI_OPCODE_RESQ                105
-                                /* gap */
+#define TGSI_OPCODE_READ_FIRST          106
 #define TGSI_OPCODE_NOP                 107
 
 #define TGSI_OPCODE_FSEQ                108
 #define TGSI_OPCODE_FSGE                109
 #define TGSI_OPCODE_FSLT                110
 #define TGSI_OPCODE_FSNE                111
 
 #define TGSI_OPCODE_MEMBAR              112
 #define TGSI_OPCODE_CALLNZ              113
                                 /* gap */
-- 
2.9.3



More information about the mesa-dev mailing list