From ab70ea1353ac9859ee51d236482fe92a0493362d Mon Sep 17 00:00:00 2001
From: Ilia Mirkin <imirkin@alum.mit.edu>
Date: Thu, 10 Dec 2015 21:20:32 -0500
Subject: [PATCH] nv50/ir: add short imad support

Support emission of the short imad, but also include it in the various
logic that tries to make it possible to emit.

Signed-off-by: Ilia Mirkin <imirkin@alum.mit.edu>
---
 .../nouveau/codegen/nv50_ir_emit_nv50.cpp     | 55 ++++++++++++-------
 .../nouveau/codegen/nv50_ir_peephole.cpp      |  6 +-
 .../drivers/nouveau/codegen/nv50_ir_ra.cpp    |  1 -
 3 files changed, 40 insertions(+), 22 deletions(-)

diff --git a/src/gallium/drivers/nouveau/codegen/nv50_ir_emit_nv50.cpp b/src/gallium/drivers/nouveau/codegen/nv50_ir_emit_nv50.cpp
index 216e119af63..00be37769af 100644
--- a/src/gallium/drivers/nouveau/codegen/nv50_ir_emit_nv50.cpp
+++ b/src/gallium/drivers/nouveau/codegen/nv50_ir_emit_nv50.cpp
@@ -1190,29 +1190,45 @@ CodeEmitterNV50::emitDMUL(const Instruction *i)
 void
 CodeEmitterNV50::emitIMAD(const Instruction *i)
 {
+   int mode;
    code[0] = 0x60000000;
-   if (isSignedType(i->sType))
-      code[1] = i->saturate ? 0x40000000 : 0x20000000;
-   else
-      code[1] = 0x00000000;
-
-   int neg1 = i->src(0).mod.neg() ^ i->src(1).mod.neg();
-   int neg2 = i->src(2).mod.neg();
 
-   assert(!(neg1 & neg2));
-   code[1] |= neg1 << 27;
-   code[1] |= neg2 << 26;
+   assert(!i->src(0).mod && !i->src(1).mod && !i->src(2).mod);
+   if (!isSignedType(i->sType))
+      mode = 0;
+   else if (i->saturate)
+      mode = 2;
+   else
+      mode = 1;
 
-   if (i->src(1).getFile() == FILE_IMMEDIATE)
+   if (i->src(1).getFile() == FILE_IMMEDIATE) {
+      code[1] = 0;
       emitForm_IMM(i);
-   else
+      code[0] |= (mode & 1) << 8 | (mode & 2) << 14;
+      if (i->flagsSrc >= 0) {
+         assert(!(code[0] & 0x10400000));
+         assert(SDATA(i->src(i->flagsSrc)).id == 0);
+         code[0] |= 0x10400000;
+      }
+   } else
+   if (i->encSize == 4) {
+      emitForm_MUL(i);
+      code[0] |= (mode & 1) << 8 | (mode & 2) << 14;
+      if (i->flagsSrc >= 0) {
+         assert(!(code[0] & 0x10400000));
+         assert(SDATA(i->src(i->flagsSrc)).id == 0);
+         code[0] |= 0x10400000;
+      }
+   } else {
+      code[1] = mode << 29;
       emitForm_MAD(i);
 
-   if (i->flagsSrc >= 0) {
-      // add with carry from $cX
-      assert(!(code[1] & 0x0c000000) && !i->getPredicate());
-      code[1] |= 0xc << 24;
-      srcId(i->src(i->flagsSrc), 32 + 12);
+      if (i->flagsSrc >= 0) {
+         // add with carry from $cX
+         assert(!(code[1] & 0x0c000000) && !i->getPredicate());
+         code[1] |= 0xc << 24;
+         srcId(i->src(i->flagsSrc), 32 + 12);
+      }
    }
 }
 
@@ -2054,8 +2070,9 @@ CodeEmitterNV50::getMinEncodingSize(const Instruction *i) const
 
    // check constraints on short MAD
    if (info.srcNr >= 2 && i->srcExists(2)) {
-      if (!i->defExists(0) || !isFloatType(i->dType) ||
-          i->def(0).rep()->reg.data.id != i->src(2).rep()->reg.data.id)
+      if (!i->defExists(0) ||
+          (i->flagsSrc >= 0 && SDATA(i->src(i->flagsSrc)).id > 0) ||
+          DDATA(i->def(0)).id != SDATA(i->src(2)).id)
          return 8;
    }
 
diff --git a/src/gallium/drivers/nouveau/codegen/nv50_ir_peephole.cpp b/src/gallium/drivers/nouveau/codegen/nv50_ir_peephole.cpp
index 23454f30e09..7f4752c0558 100644
--- a/src/gallium/drivers/nouveau/codegen/nv50_ir_peephole.cpp
+++ b/src/gallium/drivers/nouveau/codegen/nv50_ir_peephole.cpp
@@ -2804,14 +2804,16 @@ NV50PostRaConstantFolding::visit(BasicBlock *bb)
              i->src(0).getFile() != FILE_GPR ||
              i->src(1).getFile() != FILE_GPR ||
              i->src(2).getFile() != FILE_GPR ||
-             i->getDef(0)->reg.data.id != i->getSrc(2)->reg.data.id ||
-             !isFloatType(i->dType))
+             i->getDef(0)->reg.data.id != i->getSrc(2)->reg.data.id)
             break;
 
          if (i->getDef(0)->reg.data.id >= 64 ||
              i->getSrc(0)->reg.data.id >= 64)
             break;
 
+         if (i->flagsSrc >= 0 && i->getSrc(i->flagsSrc)->reg.data.id != 0)
+            break;
+
          if (i->getPredicate())
             break;
 
diff --git a/src/gallium/drivers/nouveau/codegen/nv50_ir_ra.cpp b/src/gallium/drivers/nouveau/codegen/nv50_ir_ra.cpp
index b32bc13f755..cd8c42ced5e 100644
--- a/src/gallium/drivers/nouveau/codegen/nv50_ir_ra.cpp
+++ b/src/gallium/drivers/nouveau/codegen/nv50_ir_ra.cpp
@@ -1473,7 +1473,6 @@ GCRA::allocateRegisters(ArrayList& insns)
                // Short encoding only possible if they're all GPRs, no need to
                // affect them otherwise.
                if (insn->flagsDef < 0 &&
-                   isFloatType(insn->dType) &&
                    insn->src(0).getFile() == FILE_GPR &&
                    insn->src(1).getFile() == FILE_GPR &&
                    insn->src(2).getFile() == FILE_GPR)
-- 
2.30.2