Handle mod with values < 1 && > 0

Fixes #32
captbaritone · May 16, 2021 · dfb9a2c · dfb9a2c
1 parent 3f7cb81
commit dfb9a2c
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Showing 3 changed files with 12 additions and 9 deletions.
diff --git a/packages/compiler/src/encoding.ts b/packages/compiler/src/encoding.ts
@@ -131,7 +131,7 @@ export const op = {
   i32_mul: 0x6c,
   // i32_div_s: 0x6d,
   // i32_div_u: 0x6e,
-  // i32_rem_s: 0x6f,
+  i32_rem_s: 0x6f,
   // i32_rem_u: 0x70,
   i32_and: 0x71,
   i32_or: 0x72,
@@ -160,7 +160,7 @@ export const op = {
   // f64_copysign: 0xa6,
 
   i32_trunc_f64_s: 0xaa,
-  // i32_trunc_f64_u: 0xab,
+  i32_trunc_f64_u: 0xab,
   i64_trunc_s_f64: 0xb0,
   f64_convert_i64_s: 0xb9,
   f64_convert_i32_s: 0xb7,

diff --git a/packages/compiler/src/wasmFunctions.ts b/packages/compiler/src/wasmFunctions.ts
@@ -53,18 +53,20 @@ export const localFuncMap: { [functionName: string]: FunctionDefinition } = {
   mod: {
     args: [VAL_TYPE.f64, VAL_TYPE.f64],
     returns: [VAL_TYPE.f64],
+    localVariables: [VAL_TYPE.i32],
     // TODO: Simplify all this type coersion
     binary: [
       ...op.local_get(1),
-      ...op.f64_const(0),
-      op.f64_ne,
+      op.i32_trunc_f64_s,
+      ...op.local_tee(2),
+      ...op.i32_const(0),
+      op.i32_ne,
       ...op.if(BLOCK.f64),
       ...op.local_get(0),
-      op.i64_trunc_s_f64,
-      ...op.local_get(1),
-      op.i64_trunc_s_f64,
-      op.i64_rem_s,
-      op.f64_convert_i64_s,
+      op.i32_trunc_f64_s,
+      ...op.local_get(2),
+      op.i32_rem_s,
+      op.f64_convert_i32_s,
       op.else,
       ...op.f64_const(0),
       op.end,

diff --git a/packages/compiler/tools/testCases.ts b/packages/compiler/tools/testCases.ts
@@ -16,6 +16,7 @@ const testCases: [string, string, number][] = [
   ["Divide", "g = 10 / 10;", 1],
   ["Mod", "g = 5 % 2;", 1],
   ["Mod zero", "g = 5 % 0;", 0],
+  ["Mod almost zero", "g = 5 % 0.1;", 0],
   ["Bitwise and", "g = 3 & 5;", 1],
   ["Bitwise or", "g = 3 | 5;", 7],
   ["To the power", "g = 5 ^ 2;", 25],