[Mesa-dev] [PATCH] nvc0/ir: all short immediates are sign-extended, adjust LIMM test

Ilia Mirkin imirkin at alum.mit.edu
Sat Apr 21 17:51:34 UTC 2018


Some analysis suggests that all short immediates are sign-extended. The
insnCanLoad logic already accounted for this, but we could still pick
the wrong form when emitting actual instructions that support both short
and long immediates (with the long form usually having additional
restrictions that insnCanLoad should be aware of).

This also reverses a bunch of commits that had previously "worked
around" this issue in various emitters:

9c63224540ef: gm107/ir: make use of ADD32I for all immediates
83a4f28dc27b: gm107/ir: make use of LOP32I for all immediates
b84c97587b4a: gm107/ir: make use of IMUL32I for all immediates
d30768025a22: gk110/ir: make use of IMUL32I for all immediates

as well as the original import for UMUL in the nvc0 emitter.

Reported-by: Karol Herbst <kherbst at redhat.com>
Signed-off-by: Ilia Mirkin <imirkin at alum.mit.edu>
---
 .../drivers/nouveau/codegen/nv50_ir_emit_gk110.cpp  | 10 +++++++---
 .../drivers/nouveau/codegen/nv50_ir_emit_gm107.cpp  | 21 +++++++++------------
 .../drivers/nouveau/codegen/nv50_ir_emit_nvc0.cpp   | 12 ++++++++----
 3 files changed, 24 insertions(+), 19 deletions(-)

diff --git a/src/gallium/drivers/nouveau/codegen/nv50_ir_emit_gk110.cpp b/src/gallium/drivers/nouveau/codegen/nv50_ir_emit_gk110.cpp
index 370427d0d13..647d1a5d0ef 100644
--- a/src/gallium/drivers/nouveau/codegen/nv50_ir_emit_gk110.cpp
+++ b/src/gallium/drivers/nouveau/codegen/nv50_ir_emit_gk110.cpp
@@ -207,7 +207,11 @@ bool CodeEmitterGK110::isLIMM(const ValueRef& ref, DataType ty, bool mod)
 {
    const ImmediateValue *imm = ref.get()->asImm();
 
-   return imm && (imm->reg.data.u32 & ((ty == TYPE_F32) ? 0xfff : 0xfff00000));
+   if (ty == TYPE_F32)
+      return imm && imm->reg.data.u32 & 0xfff;
+   else
+      return imm && (imm->reg.data.s32 > 0x7ffff ||
+                     imm->reg.data.s32 < -0x80000);
 }
 
 void
@@ -342,7 +346,7 @@ CodeEmitterGK110::setShortImmediate(const Instruction *i, const int s)
       code[1] |= ((u64 & 0x7fe0000000000000ULL) >> 53);
       code[1] |= ((u64 & 0x8000000000000000ULL) >> 36);
    } else {
-      assert((u32 & 0xfff00000) == 0 || (u32 & 0xfff00000) == 0xfff00000);
+      assert((u32 & 0xfff80000) == 0 || (u32 & 0xfff80000) == 0xfff80000);
       code[0] |= (u32 & 0x001ff) << 23;
       code[1] |= (u32 & 0x7fe00) >> 9;
       code[1] |= (u32 & 0x80000) << 8;
@@ -633,7 +637,7 @@ CodeEmitterGK110::emitIMUL(const Instruction *i)
    assert(!i->src(0).mod.neg() && !i->src(1).mod.neg());
    assert(!i->src(0).mod.abs() && !i->src(1).mod.abs());
 
-   if (i->src(1).getFile() == FILE_IMMEDIATE) {
+   if (isLIMM(i->src(1), TYPE_S32)) {
       emitForm_L(i, 0x280, 2, Modifier(0));
 
       if (i->subOp == NV50_IR_SUBOP_MUL_HIGH)
diff --git a/src/gallium/drivers/nouveau/codegen/nv50_ir_emit_gm107.cpp b/src/gallium/drivers/nouveau/codegen/nv50_ir_emit_gm107.cpp
index fafece81ad0..e91b11fe214 100644
--- a/src/gallium/drivers/nouveau/codegen/nv50_ir_emit_gm107.cpp
+++ b/src/gallium/drivers/nouveau/codegen/nv50_ir_emit_gm107.cpp
@@ -321,14 +321,10 @@ CodeEmitterGM107::longIMMD(const ValueRef &ref)
 {
    if (ref.getFile() == FILE_IMMEDIATE) {
       const ImmediateValue *imm = ref.get()->asImm();
-      if (isFloatType(insn->sType)) {
-         if ((imm->reg.data.u32 & 0x00000fff) != 0x00000000)
-            return true;
-      } else {
-         if ((imm->reg.data.u32 & 0xfff00000) != 0x00000000 &&
-             (imm->reg.data.u32 & 0xfff00000) != 0xfff00000)
-            return true;
-      }
+      if (isFloatType(insn->sType))
+         return imm->reg.data.u32 & 0xff;
+      else
+         return imm->reg.data.s32 > 0x7ffff || imm->reg.data.s32 < -0x80000;
    }
    return false;
 }
@@ -346,8 +342,9 @@ CodeEmitterGM107::emitIMMD(int pos, int len, const ValueRef &ref)
       } else if (insn->sType == TYPE_F64) {
          assert(!(imm->reg.data.u64 & 0x00000fffffffffffULL));
          val = imm->reg.data.u64 >> 44;
+      } else {
+         assert(!(val & 0xfff80000) || (val & 0xfff80000) == 0xfff80000);
       }
-      assert(!(val & 0xfff00000) || (val & 0xfff00000) == 0xfff00000);
       emitField( 56,   1, (val & 0x80000) >> 19);
       emitField(pos, len, (val & 0x7ffff));
    } else {
@@ -1658,7 +1655,7 @@ CodeEmitterGM107::emitLOP()
       break;
    }
 
-   if (insn->src(1).getFile() != FILE_IMMEDIATE) {
+   if (!longIMMD(insn->src(1))) {
       switch (insn->src(1).getFile()) {
       case FILE_GPR:
          emitInsn(0x5c400000);
@@ -1731,7 +1728,7 @@ CodeEmitterGM107::emitNOT()
 void
 CodeEmitterGM107::emitIADD()
 {
-   if (insn->src(1).getFile() != FILE_IMMEDIATE) {
+   if (!longIMMD(insn->src(1))) {
       switch (insn->src(1).getFile()) {
       case FILE_GPR:
          emitInsn(0x5c100000);
@@ -1773,7 +1770,7 @@ CodeEmitterGM107::emitIADD()
 void
 CodeEmitterGM107::emitIMUL()
 {
-   if (insn->src(1).getFile() != FILE_IMMEDIATE) {
+   if (!longIMMD(insn->src(1))) {
       switch (insn->src(1).getFile()) {
       case FILE_GPR:
          emitInsn(0x5c380000);
diff --git a/src/gallium/drivers/nouveau/codegen/nv50_ir_emit_nvc0.cpp b/src/gallium/drivers/nouveau/codegen/nv50_ir_emit_nvc0.cpp
index be7ac182222..d85fdda56ff 100644
--- a/src/gallium/drivers/nouveau/codegen/nv50_ir_emit_nvc0.cpp
+++ b/src/gallium/drivers/nouveau/codegen/nv50_ir_emit_nvc0.cpp
@@ -213,7 +213,11 @@ bool CodeEmitterNVC0::isLIMM(const ValueRef& ref, DataType ty)
 {
    const ImmediateValue *imm = ref.get()->asImm();
 
-   return imm && (imm->reg.data.u32 & ((ty == TYPE_F32) ? 0xfff : 0xfff00000));
+   if (ty == TYPE_F32)
+      return imm && imm->reg.data.u32 & 0xfff;
+   else
+      return imm && (imm->reg.data.s32 > 0x7ffff ||
+                     imm->reg.data.s32 < -0x80000);
 }
 
 void
@@ -352,7 +356,7 @@ CodeEmitterNVC0::setImmediate(const Instruction *i, const int s)
    } else
    if ((code[0] & 0xf) == 0x3 || (code[0] & 0xf) == 4) {
       // integer immediate
-      assert((u32 & 0xfff00000) == 0 || (u32 & 0xfff00000) == 0xfff00000);
+      assert((u32 & 0xfff80000) == 0 || (u32 & 0xfff80000) == 0xfff80000);
       assert(!(code[1] & 0xc000));
       u32 &= 0xfffff;
       code[0] |= (u32 & 0x3f) << 26;
@@ -641,7 +645,7 @@ void
 CodeEmitterNVC0::emitUMUL(const Instruction *i)
 {
    if (i->encSize == 8) {
-      if (i->src(1).getFile() == FILE_IMMEDIATE) {
+      if (isLIMM(i->src(1), TYPE_U32)) {
          emitForm_A(i, HEX64(10000000, 00000002));
       } else {
          emitForm_A(i, HEX64(50000000, 00000003));
@@ -2069,7 +2073,7 @@ CodeEmitterNVC0::emitMOV(const Instruction *i)
             assert(!(imm & 0x000fffff));
             code[0] = 0x00000318 | imm;
          } else {
-            assert(imm < 0x800 || ((int32_t)imm >= -0x800));
+            assert(imm < 0x800 && ((int32_t)imm >= -0x800));
             code[0] = 0x00000118 | (imm << 20);
          }
       } else {
-- 
2.16.1



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