From f7e6b61379ca2a55c85427818565c3d6ff722dce Mon Sep 17 00:00:00 2001
From: Tony Wasserka <tony.wasserka@gmx.de>
Date: Thu, 29 Oct 2020 11:41:11 +0100
Subject: [PATCH] aco/ra: Add helpers to test for intersection/containment of
 reg intervals
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Reviewed-by: Daniel Schürmann <daniel@schuermann.dev>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/7799>
---
 src/amd/compiler/aco_register_allocation.cpp | 25 ++++++++++++++------
 1 file changed, 18 insertions(+), 7 deletions(-)

diff --git a/src/amd/compiler/aco_register_allocation.cpp b/src/amd/compiler/aco_register_allocation.cpp
index 2b0533a2dcf..ff74900b5ea 100644
--- a/src/amd/compiler/aco_register_allocation.cpp
+++ b/src/amd/compiler/aco_register_allocation.cpp
@@ -158,6 +158,14 @@ struct PhysRegInterval {
       return { first, end - first };
    }
 
+   bool contains(PhysReg reg) const {
+       return lo() <= reg && reg < hi();
+   }
+
+   bool contains(const PhysRegInterval& needle) const {
+       return needle.lo() >= lo() && needle.hi() <= hi();
+   }
+
    PhysRegIterator begin() const {
       return { lo_ };
    }
@@ -167,6 +175,11 @@ struct PhysRegInterval {
    }
 };
 
+bool intersects(const PhysRegInterval& a, const PhysRegInterval& b) {
+   return ((a.lo() >= b.lo() && a.lo() < b.hi()) ||
+           (a.hi() > b.lo() && a.hi() <= b.hi()));
+}
+
 /* Gets the stride for full (non-subdword) registers */
 uint32_t get_stride(RegClass rc) {
     if (rc.type() == RegType::vgpr) {
@@ -811,7 +824,7 @@ std::pair<PhysReg, bool> get_reg_simple(ra_ctx& ctx,
    if (rc.is_subdword()) {
       for (std::pair<uint32_t, std::array<uint32_t, 4>> entry : reg_file.subdword_regs) {
          assert(reg_file[entry.first] == 0xF0000000);
-         if (bounds.lo() > entry.first || entry.first >= bounds.hi())
+         if (!bounds.contains(PhysReg{entry.first}))
             continue;
 
          for (unsigned i = 0; i < 4; i+= info.stride) {
@@ -943,8 +956,7 @@ bool get_regs_for_copies(ra_ctx& ctx,
       unsigned stride = var.rc.is_subdword() ? 1 : info.stride;
       for (PhysRegInterval reg_win { bounds.lo(), size };
            reg_win.hi() <= bounds.hi(); reg_win += stride) {
-         if (!is_dead_operand && ((reg_win.lo() >= def_reg.lo() && reg_win.lo() < def_reg.hi()) ||
-                                  (reg_win.hi() > def_reg.lo() && reg_win.hi() <= def_reg.hi())))
+         if (!is_dead_operand && intersects(reg_win, def_reg))
             continue;
 
          /* second, check that we have at most k=num_moves elements in the window
@@ -1048,8 +1060,7 @@ std::pair<PhysReg, bool> get_reg_impl(ra_ctx& ctx,
       Operand& op = instr->operands[j];
       if (op.isTemp() &&
           op.isFirstKillBeforeDef() &&
-          op.physReg() >= bounds.lo() &&
-          op.physReg() < bounds.hi() &&
+          bounds.contains(op.physReg()) &&
           !reg_file.test(PhysReg{op.physReg().reg()}, align(op.bytes() + op.physReg().byte(), 4))) {
          assert(op.isFixed());
 
@@ -1214,7 +1225,7 @@ bool get_reg_specified(ra_ctx& ctx,
    }
 
    PhysRegInterval reg_win = { reg.reg(), rc.size() };
-   if (reg_win.lo() < bounds.lo() || reg_win.hi() > bounds.hi())
+   if (!bounds.contains(reg_win))
       return false;
 
    if (rc.is_subdword()) {
@@ -1383,7 +1394,7 @@ PhysReg get_reg_create_vector(ra_ctx& ctx,
 
       /* check borders */
       // TODO: this can be improved */
-      if (reg_win.lo() < bounds.lo() || reg_win.hi() > bounds.hi() || reg_win.lo() % stride != 0)
+      if (!bounds.contains(reg_win) || reg_win.lo() % stride != 0)
          continue;
       if (reg_win.lo() > bounds.lo() && reg_file[reg_win.lo()] != 0 && reg_file.get_id(PhysReg(reg_win.lo())) == reg_file.get_id(PhysReg(reg_win.lo()).advance(-1)))
          continue;