[WebAssembly] Fold setne and seteq comparisons into selects.

[oota-llvm.git] / lib / Target / WebAssembly / WebAssemblyInstrFloat.td

diff --git a/lib/Target/WebAssembly/WebAssemblyInstrFloat.td b/lib/Target/WebAssembly/WebAssemblyInstrFloat.td
index 33efbb350cba62e9d507b7a4c2bb43b6a4dbdaaf..0d819581621e210ed588023c90a282a953579270 100644 (file)
--- a/lib/Target/WebAssembly/WebAssemblyInstrFloat.td
+++ b/lib/Target/WebAssembly/WebAssemblyInstrFloat.td
@@ -12,6 +12,8 @@
 ///
 //===----------------------------------------------------------------------===//
 
+let Defs = [ARGUMENTS] in {
+
 defm ADD : BinaryFP<fadd, "add ">;
 defm SUB : BinaryFP<fsub, "sub ">;
 defm MUL : BinaryFP<fmul, "mul ">;
@@ -30,10 +32,14 @@ defm FLOOR : UnaryFP<ffloor, "floor">;
 defm TRUNC : UnaryFP<ftrunc, "trunc">;
 defm NEAREST : UnaryFP<fnearbyint, "nearest">;
 
+} // Defs = [ARGUMENTS]
+
 // WebAssembly doesn't expose inexact exceptions, so map frint to fnearbyint.
 def : Pat<(frint f32:$src), (NEAREST_F32 f32:$src)>;
 def : Pat<(frint f64:$src), (NEAREST_F64 f64:$src)>;
 
+let Defs = [ARGUMENTS] in {
+
 defm EQ : ComparisonFP<SETOEQ, "eq  ">;
 defm NE : ComparisonFP<SETUNE, "ne  ">;
 defm LT : ComparisonFP<SETOLT, "lt  ">;
@@ -41,6 +47,8 @@ defm LE : ComparisonFP<SETOLE, "le  ">;
 defm GT : ComparisonFP<SETOGT, "gt  ">;
 defm GE : ComparisonFP<SETOGE, "ge  ">;
 
+} // Defs = [ARGUMENTS]
+
 // Don't care floating-point comparisons, supported via other comparisons.
 def : Pat<(seteq f32:$lhs, f32:$rhs), (EQ_F32 f32:$lhs, f32:$rhs)>;
 def : Pat<(setne f32:$lhs, f32:$rhs), (NE_F32 f32:$lhs, f32:$rhs)>;
@@ -55,9 +63,27 @@ def : Pat<(setle f64:$lhs, f64:$rhs), (LE_F64 f64:$lhs, f64:$rhs)>;
 def : Pat<(setgt f64:$lhs, f64:$rhs), (GT_F64 f64:$lhs, f64:$rhs)>;
 def : Pat<(setge f64:$lhs, f64:$rhs), (GE_F64 f64:$lhs, f64:$rhs)>;
 
+let Defs = [ARGUMENTS] in {
+
 def SELECT_F32 : I<(outs F32:$dst), (ins I32:$cond, F32:$lhs, F32:$rhs),
                    [(set F32:$dst, (select I32:$cond, F32:$lhs, F32:$rhs))],
                    "f32.select\t$dst, $cond, $lhs, $rhs">;
 def SELECT_F64 : I<(outs F64:$dst), (ins I32:$cond, F64:$lhs, F64:$rhs),
                    [(set F64:$dst, (select I32:$cond, F64:$lhs, F64:$rhs))],
                    "f64.select\t$dst, $cond, $lhs, $rhs">;
+
+} // Defs = [ARGUMENTS]
+
+// ISD::SELECT requires its operand to conform to getBooleanContents, but
+// WebAssembly's select interprets any non-zero value as true, so we can fold
+// a setne with 0 into a select.
+def : Pat<(select (i32 (setne I32:$cond, 0)), F32:$lhs, F32:$rhs),
+          (SELECT_F32 I32:$cond, F32:$lhs, F32:$rhs)>;
+def : Pat<(select (i32 (setne I32:$cond, 0)), F64:$lhs, F64:$rhs),
+          (SELECT_F64 I32:$cond, F64:$lhs, F64:$rhs)>;
+
+// And again, this time with seteq instead of setne and the arms reversed.
+def : Pat<(select (i32 (seteq I32:$cond, 0)), F32:$lhs, F32:$rhs),
+          (SELECT_F32 I32:$cond, F32:$rhs, F32:$lhs)>;
+def : Pat<(select (i32 (seteq I32:$cond, 0)), F64:$lhs, F64:$rhs),
+          (SELECT_F64 I32:$cond, F64:$rhs, F64:$lhs)>;