Inline const values of type int,float,bool

e.g.
  const bool debug = false;
  const int steps = 5;

are inlined by default

src/analyzer.fs

@@ -80,13 +80,22 @@ let findInlinable block =
             | (false, _), (false, _) -> ident.ToBeInlined <- true
             | _ -> ()
 
-let inlineAllConsts li =
+let maybeInlineConsts li =
     let mapInnerDecl = function
-        // Unconditional inlining of anything marked "const" -- trust that the
-        // compiler would have yelled if it weren't really really const, so we
-        // can brutishly just inline it.
         | ({typeQ = tyQ}, defs) as d when List.contains "const" tyQ ->
-            for (def:DeclElt) in defs do def.name.ToBeInlined <- true
+            for (def:DeclElt) in defs do
+                // AggroInlining: unconditional inlining of anything marked "const".
+                // Note: this is unsafe if the init value depends on something mutable.
+                if options.aggroInlining then
+                    def.name.ToBeInlined <- true
+                // Otherwise, inline only trivial constants.
+                else match def.init with
+                        | Some (Var v) when v.Name = "true" || v.Name = "false" ->
+                            def.name.ToBeInlined <- true
+                        | Some (Int _)
+                        | Some (Float _) ->
+                            def.name.ToBeInlined <- true
+                        | _ -> ()
             d
         | d -> d
     let mapStmt = function

src/rewriter.fs

@@ -342,7 +342,7 @@ let simplify li =
     // but we only need the information for aggroInlining so don't bother if
     // it's off.
     |> Analyzer.markLValues
-    |> if options.aggroInlining then Analyzer.inlineAllConsts else id
+    |> Analyzer.maybeInlineConsts
     |> iterateSimplifyAndInline
     |> List.choose (function
         | TLDecl (ty, li) -> TLDecl (rwType ty, declsNotToInline li) |> Some

tests/real/ed-209.frag.expected

@@ -126,11 +126,10 @@ MarchData gunPod(vec3 p)
   MarchData r;
   setBodyMaterial(r);
   p.yz+=vec2(.1,.45);
-  const float rr=.35,chamfer=.1;
   vec3 pp=p;
   pp.z=abs(pp.z)-.5;
-  r.d=sdCappedCone(pp,vec3(0),vec3(0,0,-chamfer),rr-chamfer,rr);
-  r.d=min(r.d,sdCappedCylinder(p,rr,.4));
+  r.d=sdCappedCone(pp,vec3(0),vec3(0,0,-.1),.25,.35);
+  r.d=min(r.d,sdCappedCylinder(p,.35,.4));
   pp=vec3(p.x,.28-p.y,p.z);
   r.d=min(r.d,sdTriPrism(pp,vec2(.1,.5)));
   pp=p;

tests/real/from-the-seas-to-the-stars.frag.expected

@@ -818,8 +818,7 @@ void main()
       if(coord.x<1280&&coord.y<720)
         {
           vec4 c=vec4(0);
-          const int sampleCount=8;
-          for(int sampleIndex=0;sampleIndex<sampleCount;++sampleIndex)
+          for(int sampleIndex=0;sampleIndex<8;++sampleIndex)
             {
               uint x=imageLoad(d0,coord,sampleIndex).x,idepth=x>>16,icol=x&65535;
               if(idepth==0)
@@ -840,7 +839,7 @@ void main()
               c.xyz+=clamp(col,0,1);
               c.w+=1.;
             }
-          c/=float(sampleCount);
+          c/=float(8);
           vec3 bg=vec3(.02)*vec3(.7,.9,1)*.6;
           if(time>=200)
             bg*=max(0.,1.-(time-200)/7.);

tests/real/mandelbulb.expected

@@ -7,115 +7,113 @@
 const char *mandelbulb_frag =
  "uniform vec2 resolution;"
  "uniform float time;"
- "bool f(vec4 v,vec3 f,vec3 y,out vec2 i)"
+ "bool t(vec4 v,vec3 f,vec3 t,out vec2 i)"
  "{"
-   "vec3 x=f-v.xyz;"
-   "float c=dot(x,y),e=dot(x,x)-v.w*v.w,o=c*c-e;"
+   "vec3 y=f-v.xyz;"
+   "float c=dot(y,t),e=dot(y,y)-v.w*v.w,o=c*c-e;"
    "if(o<0.)"
      "return false;"
-   "float t=sqrt(o);"
-   "i.x=-c-t;"
-   "i.y=-c+t;"
+   "float x=sqrt(o);"
+   "i.x=-c-x;"
+   "i.y=-c+x;"
    "return true;"
  "}"
- "const int e=7;"
- "const float y=100.;"
- "bool f(vec3 v,out float f,out vec4 o)"
+ "bool t(vec3 v,out float f,out vec4 y)"
  "{"
    "vec4 i=vec4(100);"
    "vec3 c=v;"
-   "float x=dot(c,c);"
-   "if(x>y)"
-     "return f=.5*log(x)/pow(8.,0.),o=vec4(1),false;"
-   "for(int t=1;t<e;t++)"
+   "float o=dot(c,c);"
+   "if(o>100.)"
+     "return f=.5*log(o)/pow(8.,0.),y=vec4(1),false;"
+   "for(int x=1;x<7;x++)"
      "{"
        "\n#if 0\n"
-       "float z=sqrt(dot(c,c)),s=acos(c.y/z),n=atan(c.x,c.z);"
-       "z=pow(z,8.);"
+       "float t=sqrt(dot(c,c)),s=acos(c.y/t),n=atan(c.x,c.z);"
+       "t=pow(t,8.);"
        "s=s*8.;"
        "n=n*8.;"
-       "c=v+z*vec3(sin(s)*sin(n),cos(s),sin(s)*cos(n));"
+       "c=v+t*vec3(sin(s)*sin(n),cos(s),sin(s)*cos(n));"
        "\n#else\n"
-       "float d=c.x,m=d*d,p=m*m,l=c.y,r=l*l,a=c.z,w=a*a,g=w*w,u=m+w,q=inversesqrt(u*u*u*u*u*u*u),b=p+r*r+g-6.*r*w-6.*m*r+2.*w*m,F=m-r+w;"
-       "c.x=v.x+64.*d*l*a*(m-w)*F*(p-6.*m*w+g)*b*q;"
-       "c.y=v.y+-16.*r*u*F*F+b*b;"
-       "c.z=v.z+-8.*l*F*(p*p-28.*p*m*w+70.*p*g-28.*m*w*g+g*g)*b*q;"
+       "float d=c.x,z=d*d,m=z*z,p=c.y,e=p*p,l=c.z,w=l*l,r=w*w,g=z+w,a=inversesqrt(g*g*g*g*g*g*g),u=m+e*e+r-6.*e*w-6.*z*e+2.*w*z,q=z-e+w;"
+       "c.x=v.x+64.*d*p*l*(z-w)*q*(m-6.*z*w+r)*u*a;"
+       "c.y=v.y+-16.*e*g*q*q+u*u;"
+       "c.z=v.z+-8.*p*q*(m*m-28.*m*z*w+70.*m*r-28.*z*w*r+r*r)*u*a;"
        "\n#endif\n"
-       "x=dot(c,c);"
-       "i=min(i,vec4(c.xyz*c.xyz,x));"
-       "if(x>y)"
-         "return o=i,f=.5*log(x)/pow(8.,float(t)),false;"
+       "o=dot(c,c);"
+       "i=min(i,vec4(c.xyz*c.xyz,o));"
+       "if(o>100.)"
+         "return y=i,f=.5*log(o)/pow(8.,float(x)),false;"
      "}"
-   "o=i;"
+   "y=i;"
    "f=0.;"
    "return true;"
  "}"
- "bool f(vec3 v,vec3 c,out float o,float y,out vec3 x,out vec4 t,float u)"
+ "bool t(vec3 v,vec3 f,out float y,float c,out vec3 o,out vec4 x,float g)"
  "{"
    "vec4 i=vec4(0,0,0,1.25);"
-   "vec2 e;"
-   "if(!f(i,v,c,e))"
+   "vec2 s;"
+   "if(!t(i,v,f,s))"
      "return false;"
-   "if(e.y<.001)"
+   "if(s.y<.001)"
      "return false;"
-   "if(e.x<.001)"
-     "e.x=.001;"
-   "if(e.y>y)"
-     "e.y=y;"
-   "float n;"
-   "vec3 s;"
-   "vec4 m;"
-   "float w=1./sqrt(1.+u*u);"
-   "for(float r=e.x;r<e.y;)"
+   "if(s.x<.001)"
+     "s.x=.001;"
+   "if(s.y>c)"
+     "s.y=c;"
+   "float e;"
+   "vec3 n;"
+   "vec4 z;"
+   "float w=1./sqrt(1.+g*g);"
+   "for(float m=s.x;m<s.y;)"
      "{"
-       "vec3 z=v+c*r;"
-       "float d=clamp(.001*r*w,1e-6,.005),p=d*.1;"
-       "vec4 q;"
+       "vec3 r=v+f*m;"
+       "float d=clamp(.001*m*w,1e-6,.005),p=d*.1;"
+       "vec4 a;"
        "float l;"
-       "if(f(z,l,m))"
-         "return o=r,x=normalize(s),t=m,true;"
-       "float g;"
-       "f(z+vec3(p,0,0),g,q);"
-       "float a;"
-       "f(z+vec3(0,p,0),a,q);"
+       "if(t(r,l,z))"
+         "return y=m,o=normalize(n),x=z,true;"
+       "float u;"
+       "t(r+vec3(p,0,0),u,a);"
+       "float q;"
+       "t(r+vec3(0,p,0),q,a);"
        "float b;"
-       "f(z+vec3(0,0,p),b,q);"
-       "s=vec3(g-l,a-l,b-l);"
-       "n=.5*l*p/length(s);"
-       "if(n<d)"
-         "return t=m,x=normalize(s),o=r,true;"
-       "r+=n;"
+       "t(r+vec3(0,0,p),b,a);"
+       "n=vec3(u-l,q-l,b-l);"
+       "e=.5*l*p/length(n);"
+       "if(e<d)"
+         "return x=z,o=normalize(n),y=m,true;"
+       "m+=e;"
      "}"
    "return false;"
  "}"
  "void main()"
  "{"
    "vec2 v=-1.+2.*gl_FragCoord.xy/resolution.xy,c=v*vec2(1.33,1);"
-   "vec3 x=vec3(.577),o=vec3(-.707,0,.707);"
+   "vec3 f=vec3(.577),o=vec3(-.707,0,.707);"
    "float y=1.,s=1.4+.2*cos(6.28318*time/20.);"
-   "vec3 z=vec3(s*sin(6.28318*time/20.),.3-.4*sin(6.28318*time/20.),s*cos(6.28318*time/20.)),p=vec3(0,.1,0),m=normalize(p-z),t=vec3(0,1,0),r=normalize(cross(m,t)),w=normalize(cross(r,m)),e=normalize(c.x*r+c.y*w+1.5*m),l,i;"
-   "vec4 u;"
-   "float b;"
-   "if(!f(z,e,b,1e20,l,u,y))"
-     "i=1.3*vec3(1,.98,.9)*(.7+.3*e.y);"
+   "vec3 n=vec3(s*sin(6.28318*time/20.),.3-.4*sin(6.28318*time/20.),s*cos(6.28318*time/20.)),r=vec3(0,.1,0),z=normalize(r-n),x=vec3(0,1,0),p=normalize(cross(z,x)),e=normalize(cross(p,z)),w=normalize(c.x*p+c.y*e+1.5*z),g,i;"
+   "vec4 l;"
+   "float u;"
+   "if(!t(n,w,u,1e20,g,l,y))"
+     "i=1.3*vec3(1,.98,.9)*(.7+.3*w.y);"
    "else"
      "{"
-       "vec3 n=z+b*e;"
-       "float d=clamp(.2+.8*dot(x,l),0.,1.);"
+       "vec3 m=n+u*w;"
+       "float d=clamp(.2+.8*dot(f,g),0.,1.);"
        "d=d*d;"
-       "float F=clamp(.3+.7*dot(o,l),0.,1.),a=clamp(1.25*u.w-.4,0.,1.);"
+       "float q=clamp(.3+.7*dot(o,g),0.,1.),a=clamp(1.25*l.w-.4,0.,1.);"
        "a=a*a*.5+.5*a;"
-       "float q;"
-       "vec3 g;"
+       "float b;"
+       "vec3 F;"
        "vec4 C;"
        "if(d>.001)"
-         "if(f(n,x,q,1e20,g,C,y))"
+         "if(t(m,f,b,1e20,F,C,y))"
            "d=.1;"
        "i=vec3(1);"
-       "i=mix(i,vec3(.8,.6,.2),sqrt(u.x)*1.25);"
-       "i=mix(i,vec3(.8,.3,.3),sqrt(u.y)*1.25);"
-       "i=mix(i,vec3(.7,.4,.3),sqrt(u.z)*1.25);"
-       "i*=(.5+.5*l.y)*vec3(.14,.15,.16)*.8+d*vec3(1,.85,.4)+.5*F*vec3(.08,.1,.14);"
+       "i=mix(i,vec3(.8,.6,.2),sqrt(l.x)*1.25);"
+       "i=mix(i,vec3(.8,.3,.3),sqrt(l.y)*1.25);"
+       "i=mix(i,vec3(.7,.4,.3),sqrt(l.z)*1.25);"
+       "i*=(.5+.5*g.y)*vec3(.14,.15,.16)*.8+d*vec3(1,.85,.4)+.5*q*vec3(.08,.1,.14);"
        "i*=vec3(pow(a,.8),pow(a,1.),pow(a,1.1));"
        "i=1.5*(i*.15+.85*sqrt(i));"
      "}"

tests/real/yx_long_way_from_home.frag.expected

@@ -123,37 +123,36 @@ const char *yx_long_way_from_home_frag =
  "vec3 h(vec3 v,vec3 x)"
  "{"
    "vec3 y=normalize(vec3(.3,.36,-1));"
-   "const float z=1e-4;"
-   "const vec3 n=vec3(1,.6,.2)*2.;"
-   "vec3 r=vec3(1),c=vec3(0);"
-   "for(int m=0;m<10;++m)"
+   "const vec3 z=vec3(1,.6,.2)*2.;"
+   "vec3 n=vec3(1),c=vec3(0);"
+   "for(int r=0;r<10;++r)"
      "{"
        "vec3 t,l;"
        "float a;"
        "if(d(v,x,t,l,a))"
          "{"
-           "float p=1.;"
-           "vec3 g=vec3(1);"
+           "float m=1.;"
+           "vec3 p=vec3(1);"
            "if(f==1)"
-             "g=vec3(.7);"
-           "p*=p;"
+             "p=vec3(.7);"
+           "m*=m;"
            "{"
              "v=t+l*.002;"
              "vec3 h=reflect(x,l),o=e(l,1.);"
-             "x=normalize(mix(h,o,p));"
-             "r*=g;"
+             "x=normalize(mix(h,o,m));"
+             "n*=p;"
            "}"
-           "vec3 o=d(y,z);"
+           "vec3 o=d(y,1e-4);"
            "float h=dot(l,o);"
-           "vec3 b,k;"
-           "float S;"
-           "if(h>0.&&!d(t+l*.002,o,b,k,S))"
-             "c+=r*h*n;"
+           "vec3 g,k;"
+           "float b;"
+           "if(h>0.&&!d(t+l*.002,o,g,k,b))"
+             "c+=n*h*z;"
            "i=s(i.y);"
          "}"
        "else"
          " if(abs(a)>.1)"
-           "return c+d(x)*r;"
+           "return c+d(x)*n;"
          "else"
            " break;"
      "}"
@@ -176,20 +175,20 @@ const char *yx_long_way_from_home_frag =
    "v.x*=iResolution.x/iResolution.y;"
    "const vec3 f=vec3(-4,2,3),y=vec3(0);"
    "const float z=distance(f,y);"
-   "const vec2 r=vec2(1,2)*.015;"
-   "vec3 c=vec3(0),o=normalize(vec3(v,2));"
-   "vec2 t=d();"
-   "c.xy+=t*r;"
-   "o.xy-=t*r*o.z/z;"
+   "const vec2 p=vec2(1,2)*.015;"
+   "vec3 c=vec3(0),r=normalize(vec3(v,2));"
+   "vec2 m=d();"
+   "c.xy+=m*p;"
+   "r.xy-=m*p*r.z/z;"
    "vec3 l=y-f;"
-   "float a=-atan(l.y,length(l.xz)),m=-atan(l.x,l.z);"
+   "float a=-atan(l.y,length(l.xz)),o=-atan(l.x,l.z);"
    "c.yz*=n(a);"
-   "o.yz*=n(a);"
-   "c.xz*=n(m);"
-   "o.xz*=n(m);"
+   "r.yz*=n(a);"
+   "c.xz*=n(o);"
+   "r.xz*=n(o);"
    "c+=f;"
-   "vec4 g=vec4(h(c,o),1);"
-   "gl_FragColor=!isnan(g.x)&&g.x>=0.?g:vec4(0);"
+   "vec4 t=vec4(h(c,r),1);"
+   "gl_FragColor=!isnan(t.x)&&t.x>=0.?t:vec4(0);"
  "}";
 
 #endif // YX_LONG_WAY_FROM_HOME_FRAG_EXPECTED_

tests/unit/conditionals.frag

@@ -36,3 +36,13 @@ bool and2() {
 bool and3() {
   return success() && true;
 }
+
+const int debug = false;
+
+int foo() {
+  int a = 1;
+  if (debug) {
+    a = 2;
+  }
+  return a;
+}

tests/unit/conditionals.frag.expected

@@ -38,3 +38,8 @@ bool and3()
 {
   return success();
 }
+int foo()
+{
+  int a=1;
+  return a;
+}

tests/unit/inline-aggro.expected

@@ -22,10 +22,9 @@ float inl4()
   const float f=acos(-1.);
   return 2.*f*.75;
 }
-const float foo=123.;
 float inl5()
 {
-  return foo+456.;
+  return 579.;
 }
 const float bar=acos(-1.),baz=2.*bar;
 float inl6()