Neg modifier for source in MIN and MAX ops is ignored.
Tested on git 89b9ef9.
I tested it only on NV96.

shader with:
float x = -sin(uv.x);
float d = max(0.0, x);
generates:
EMIT: presin f32 $r0 $r0 (8)
EMIT: sin f32 $r0 $r0 (8)
EMIT: mov u32 $r1 0x00000000 (8)
EMIT: max f32 $r2 neg $r0 $r1 (8)

Shader output is identical to version without unary minus.
Only difference is lack of neg modifier.

After disabling modifiers shader works as expected:

--- a/src/gallium/drivers/nouveau/codegen/nv50_ir_target_nv50.cpp
+++ b/src/gallium/drivers/nouveau/codegen/nv50_ir_target_nv50.cpp
@@ -85,8 +85,8 @@ static const struct opProperties _initProps[] =
    { OP_ADD,    0x3, 0x0, 0x0, 0x8, 0x2, 0x1, 0x1, 0x2 },
    { OP_SUB,    0x3, 0x0, 0x0, 0x0, 0x2, 0x1, 0x1, 0x2 },
    { OP_MUL,    0x3, 0x0, 0x0, 0x0, 0x2, 0x1, 0x1, 0x2 },
-   { OP_MAX,    0x3, 0x3, 0x0, 0x0, 0x2, 0x1, 0x1, 0x0 },
-   { OP_MIN,    0x3, 0x3, 0x0, 0x0, 0x2, 0x1, 0x1, 0x0 },
+   { OP_MAX,    0x0, 0x3, 0x0, 0x0, 0x2, 0x1, 0x1, 0x0 },
+   { OP_MIN,    0x0, 0x3, 0x0, 0x0, 0x2, 0x1, 0x1, 0x0 },
    { OP_MAD,    0x7, 0x0, 0x0, 0x0, 0x6, 0x1, 0x1, 0x0 }, // special
constraint
    { OP_ABS,    0x0, 0x0, 0x0, 0x0, 0x0, 0x1, 0x1, 0x0 },
    { OP_NEG,    0x0, 0x1, 0x0, 0x0, 0x0, 0x1, 0x1, 0x0 },

After this change:
EMIT: presin f32 $r0 $r0 (8)
EMIT: sin f32 $r0 $r0 (8)
EMIT: mov u32 $r1 0x00000000 (8)
EMIT: neg f32 $r0 $r0 (8)
EMIT: max f32 $r2 $r0 $r1 (8)