[Mesa-dev] [PATCH 14/16] glsl: Add ir_binop_mul to get_range

[Thomas Helland]

---
 src/glsl/opt_minmax.cpp | 33 +++++++++++++++++++++++++++++++++
 1 file changed, 33 insertions(+)

diff --git a/src/glsl/opt_minmax.cpp b/src/glsl/opt_minmax.cpp
index 9d300d3..49a816e 100644
--- a/src/glsl/opt_minmax.cpp
+++ b/src/glsl/opt_minmax.cpp
@@ -344,6 +344,39 @@ get_range(ir_rvalue *rval)
             high = sub(r0.high, r1.low)->constant_expression_value();
          return minmax_range(low, high);
 
+      case ir_binop_mul:
+         r0 = get_range(expr->operands[0]);
+         r1 = get_range(expr->operands[1]);
+         // Both are positive, result is positive
+         if (r0.low && is_greater_than_or_equal_zero(r0.low) &&
+            r1.low && is_greater_than_or_equal_zero(r1.low)) {
+            low = mul(r0.low, r1.low)->constant_expression_value();
+            if (r0.high && r1.high)
+               high = mul(r0.high, r1.high)->constant_expression_value();
+         }
+         // Both are negative, result is positive
+         if (r0.high && is_less_than_or_equal_zero(r0.high) &&
+            r1.high && is_less_than_or_equal_zero(r1.high)) {
+            low = mul(r0.high, r1.high)->constant_expression_value();
+            if (r0.low && r1.low)
+               high = mul(r0.low, r1.low)->constant_expression_value();
+         }
+         // r0 positive, r1 negative, result is negative
+         if (r0.low && is_greater_than_or_equal_zero(r0.low) &&
+            r1.high && is_less_than_or_equal_zero(r1.high)) {
+            high = mul(r0.low, r1.high)->constant_expression_value();
+            if (r0.high && r1.low)
+               low = mul(r0.high, r1.low)->constant_expression_value();
+         }
+         // r0 negative, r1 positive, result is negative
+         if (r1.low && is_greater_than_or_equal_zero(r1.low) &&
+            r0.high && is_less_than_or_equal_zero(r0.high)) {
+            high = mul(r0.high, r1.low)->constant_expression_value();
+            if (r0.low && r1.high)
+               low = mul(r0.low, r1.high)->constant_expression_value();
+         }
+         return minmax_range(low, high);
+
       case ir_binop_pow:
          r0 = get_range(expr->operands[0]);
          if (is_greater_than_or_equal_zero(r0.low))
-- 
2.0.3