From dfd88da8cffd29b58c1039147ed35a2b3191632c Mon Sep 17 00:00:00 2001
From: Tom Schuster <evilpies@gmail.com>
Date: Tue, 23 Jun 2020 10:14:07 +0000
Subject: [PATCH] Bug 1646975 - Transpile ToString instructions. r=jandem

Differential Revision: https://phabricator.services.mozilla.com/D80359
---
 js/src/jit-test/tests/warp/booleantostring.js |  9 +++++
 js/src/jit/CacheIROps.yaml                    |  6 +--
 js/src/jit/WarpCacheIRTranspiler.cpp          | 38 +++++++++++++++++++
 3 files changed, 50 insertions(+), 3 deletions(-)
 create mode 100644 js/src/jit-test/tests/warp/booleantostring.js

diff --git a/js/src/jit-test/tests/warp/booleantostring.js b/js/src/jit-test/tests/warp/booleantostring.js
new file mode 100644
index 000000000000..39ff0b1b6d0e
--- /dev/null
+++ b/js/src/jit-test/tests/warp/booleantostring.js
@@ -0,0 +1,9 @@
+var a = [true, false];
+for (var i = 0; i < 1e4; i++) {
+	var str = "x: " + a[i & 1];
+	if (i & 1) {
+		assertEq(str, "x: false");
+	} else {
+		assertEq(str, "x: true");
+	}
+}
diff --git a/js/src/jit/CacheIROps.yaml b/js/src/jit/CacheIROps.yaml
index 1db651dec92c..59aec63ef404 100644
--- a/js/src/jit/CacheIROps.yaml
+++ b/js/src/jit/CacheIROps.yaml
@@ -1046,7 +1046,7 @@
 
 - name: CallInt32ToString
   shared: true
-  transpile: false
+  transpile: true
   cost_estimate: 4
   args:
     input: Int32Id
@@ -1054,7 +1054,7 @@
 
 - name: CallNumberToString
   shared: true
-  transpile: false
+  transpile: true
   cost_estimate: 4
   args:
     input: NumberId
@@ -1062,7 +1062,7 @@
 
 - name: BooleanToString
   shared: true
-  transpile: false
+  transpile: true
   cost_estimate: 2
   args:
     input: Int32Id
diff --git a/js/src/jit/WarpCacheIRTranspiler.cpp b/js/src/jit/WarpCacheIRTranspiler.cpp
index 7ca97e9adfee..117d2937ad45 100644
--- a/js/src/jit/WarpCacheIRTranspiler.cpp
+++ b/js/src/jit/WarpCacheIRTranspiler.cpp
@@ -108,6 +108,8 @@ class MOZ_RAII WarpCacheIRTranspiler : public WarpBuilderShared {
 
   MOZ_MUST_USE bool emitGuardTo(ValOperandId inputId, MIRType type);
 
+  MOZ_MUST_USE bool emitToString(OperandId inputId, StringOperandId resultId);
+
   template <typename T>
   MOZ_MUST_USE bool emitDoubleBinaryArithResult(NumberOperandId lhsId,
                                                 NumberOperandId rhsId);
@@ -486,6 +488,42 @@ bool WarpCacheIRTranspiler::emitGuardToInt32ModUint32(ValOperandId valId,
   return defineOperand(resultId, ins);
 }
 
+bool WarpCacheIRTranspiler::emitToString(OperandId inputId,
+                                         StringOperandId resultId) {
+  MDefinition* input = getOperand(inputId);
+  auto* ins =
+      MToString::New(alloc(), input, MToString::SideEffectHandling::Bailout);
+  add(ins);
+
+  return defineOperand(resultId, ins);
+}
+
+bool WarpCacheIRTranspiler::emitCallInt32ToString(Int32OperandId inputId,
+                                                  StringOperandId resultId) {
+  return emitToString(inputId, resultId);
+}
+
+bool WarpCacheIRTranspiler::emitCallNumberToString(NumberOperandId inputId,
+                                                   StringOperandId resultId) {
+  return emitToString(inputId, resultId);
+}
+
+bool WarpCacheIRTranspiler::emitBooleanToString(Int32OperandId inputId,
+                                                StringOperandId resultId) {
+  MDefinition* input = getOperand(inputId);
+
+  // Remove the MToIntegerInt32 instruction added by emitGuardToBoolean.
+  // TODO: Bug 1647602 add a BooleanOperandId.
+  MDefinition* boolean = input->toToIntegerInt32()->input();
+  MOZ_ASSERT(boolean->type() == MIRType::Boolean);
+
+  auto* ins =
+      MToString::New(alloc(), boolean, MToString::SideEffectHandling::Bailout);
+  add(ins);
+
+  return defineOperand(resultId, ins);
+}
+
 bool WarpCacheIRTranspiler::emitLoadInt32Result(Int32OperandId valId) {
   MDefinition* val = getOperand(valId);
   MOZ_ASSERT(val->type() == MIRType::Int32);