diff --git a/basis/compiler/cfg/builder/builder.factor b/basis/compiler/cfg/builder/builder.factor
index 8dec435b9c..370f3d053f 100644
--- a/basis/compiler/cfg/builder/builder.factor
+++ b/basis/compiler/cfg/builder/builder.factor
@@ -137,7 +137,7 @@ M: #recursive emit-node
 : emit-actual-if ( #if -- )
     ! Inputs to the final instruction need to be copied because of
     ! loc>vreg sync
-    ds-pop any-rep ^^copy \ f type-number cc/= ##compare-imm-branch emit-if ;
+    ds-pop any-rep ^^copy f cc/= ##compare-imm-branch emit-if ;
 
 M: #if emit-node
     {
diff --git a/basis/compiler/cfg/value-numbering/rewrite/rewrite.factor b/basis/compiler/cfg/value-numbering/rewrite/rewrite.factor
index 398c73c32c..81f39d7da2 100644
--- a/basis/compiler/cfg/value-numbering/rewrite/rewrite.factor
+++ b/basis/compiler/cfg/value-numbering/rewrite/rewrite.factor
@@ -134,17 +134,12 @@ M: ##compare-imm rewrite-tagged-comparison
     } cond
     swap cc= eq? [ [ negate-cc ] change-cc ] when ;
 
-ERROR: bad-comparison ;
-
 : (fold-compare-imm) ( insn -- ? )
-    [ [ src1>> vreg>constant ] [ src2>> ] bi ] [ cc>> ] bi
-    pick integer?
-    [ [ <=> ] dip evaluate-cc ]
-    [
-        2nip {
-            { cc= [ f ] }
-            { cc/= [ t ] }
-            [ bad-comparison ]
+    [ src1>> vreg>constant ] [ src2>> ] [ cc>> ] tri
+    2over [ integer? ] both? [ [ <=> ] dip evaluate-cc ] [
+        {
+            { cc= [ eq? ] }
+            { cc/= [ eq? not ] }
         } case
     ] if ;
 
@@ -253,7 +248,12 @@ M: ##shl-imm constant-fold* drop shift ;
 
 : constant-fold ( insn -- insn' )
     [ dst>> ]
-    [ [ src1>> vreg>constant ] [ src2>> ] [ ] tri constant-fold* ] bi
+    [
+        [ src1>> vreg>constant \ f type-number or ]
+        [ src2>> ]
+        [ ]
+        tri constant-fold*
+    ] bi
     \ ##load-immediate new-insn ; inline
 
 : unary-constant-fold? ( insn -- ? )
@@ -379,7 +379,7 @@ M: ##sar-imm rewrite
         [ drop f ]
     } cond ;
 
-: insn>imm-insn ( insn op swap? -- )
+: insn>imm-insn ( insn op swap? -- new-insn )
     swap [
         [ [ dst>> ] [ src1>> ] [ src2>> ] tri ] dip
         [ swap ] when vreg>constant
@@ -389,13 +389,13 @@ M: ##sar-imm rewrite
     arithmetic-op?
     [ vreg-immediate-arithmetic? ] [ vreg-immediate-bitwise? ] if ;
 
-: rewrite-arithmetic ( insn op -- ? )
+: rewrite-arithmetic ( insn op -- insn/f )
     {
         { [ over src2>> over vreg-immediate? ] [ f insn>imm-insn ] }
         [ 2drop f ]
     } cond ; inline
 
-: rewrite-arithmetic-commutative ( insn op -- ? )
+: rewrite-arithmetic-commutative ( insn op -- insn/f )
     {
         { [ over src2>> over vreg-immediate? ] [ f insn>imm-insn ] }
         { [ over src1>> over vreg-immediate? ] [ t insn>imm-insn ] }
diff --git a/basis/compiler/cfg/value-numbering/value-numbering-tests.factor b/basis/compiler/cfg/value-numbering/value-numbering-tests.factor
index 7e41df69d6..f835200702 100644
--- a/basis/compiler/cfg/value-numbering/value-numbering-tests.factor
+++ b/basis/compiler/cfg/value-numbering/value-numbering-tests.factor
@@ -519,6 +519,59 @@ cpu x86.32? [
     } value-numbering-step trim-temps
 ] unit-test
 
+! Branch folding
+[
+    {
+        T{ ##load-immediate f 1 100 }
+        T{ ##load-immediate f 2 200 }
+        T{ ##load-constant f 3 t }
+    }
+] [
+    {
+        T{ ##load-immediate f 1 100 }
+        T{ ##load-immediate f 2 200 }
+        T{ ##compare f 3 1 2 cc<= }
+    } value-numbering-step trim-temps
+] unit-test
+
+[
+    {
+        T{ ##load-immediate f 1 100 }
+        T{ ##load-immediate f 2 200 }
+        T{ ##load-constant f 3 f }
+    }
+] [
+    {
+        T{ ##load-immediate f 1 100 }
+        T{ ##load-immediate f 2 200 }
+        T{ ##compare f 3 1 2 cc= }
+    } value-numbering-step trim-temps
+] unit-test
+
+[
+    {
+        T{ ##load-immediate f 1 100 }
+        T{ ##load-constant f 2 f }
+    }
+] [
+    {
+        T{ ##load-immediate f 1 100 }
+        T{ ##compare-imm f 2 1 f cc= }
+    } value-numbering-step trim-temps
+] unit-test
+
+[
+    {
+        T{ ##load-constant f 1 f }
+        T{ ##load-constant f 2 t }
+    }
+] [
+    {
+        T{ ##load-constant f 1 f }
+        T{ ##compare-imm f 2 1 f cc= }
+    } value-numbering-step trim-temps
+] unit-test
+
 ! Reassociation
 [
     {
@@ -1042,6 +1095,19 @@ cell 8 = [
     } value-numbering-step
 ] unit-test
 
+! Stupid constant folding corner case
+[
+    {
+        T{ ##load-constant f 1 f }
+        T{ ##load-immediate f 2 $[ \ f type-number ] }
+    }
+] [
+    {
+        T{ ##load-constant f 1 f }
+        T{ ##and-imm f 2 1 15 }
+    } value-numbering-step
+] unit-test
+
 ! Displaced alien optimizations
 3 vreg-counter set-global
 
diff --git a/basis/cpu/x86/x86.factor b/basis/cpu/x86/x86.factor
index 220db859d0..bab90c0f09 100644
--- a/basis/cpu/x86/x86.factor
+++ b/basis/cpu/x86/x86.factor
@@ -521,7 +521,7 @@ M:: x86 %compare ( dst src1 src2 cc temp -- )
         { [ 3dup use-test? ] [ 2drop dup TEST ] }
         { [ over integer? ] [ drop CMP ] }
         { [ over word? ] [ drop (%compare-tagged) ] }
-        { [ over not ] [ 2drop f type-number CMP ] }
+        { [ over not ] [ 2drop \ f type-number CMP ] }
     } cond ;
 
 M:: x86 %compare-imm ( dst src1 src2 cc temp -- )