[builtins] Pass correct number of arguments after adapting arguments.

The call protocol requires that the register dedicated to the number of
actual arguments (i.e. rax on x64) always contains the actual arguments.
That means after adapting arguments it should match the number of
expected arguments.  But currently we pass some semi-random value
(usually some stack address) after adapting arguments.

It looks like this is currently not observable anywhere, because our
builtins and functions either don't look at the number of arguments and
just make hard coded (unchecked) assumptions, or are marked as "don't
adapt arguments", which bypasses the broken code in the trampoline for
arguments adaption.  Nevertheless this should be fixed.

R=mstarzinger@chromium.org

Review URL: https://codereview.chromium.org/1306423003

Cr-Commit-Position: refs/heads/master@{#30467}

diff --git a/src/arm/builtins-arm.cc b/src/arm/builtins-arm.cc
index 79f1cda..ab2d77e 100644 (file)
--- a/src/arm/builtins-arm.cc
+++ b/src/arm/builtins-arm.cc
@@ -1755,7 +1755,7 @@ void Builtins::Generate_ArgumentsAdaptorTrampoline(MacroAssembler* masm) {
     __ bind(&enough);
     EnterArgumentsAdaptorFrame(masm);
 
-    // Calculate copy start address into r0 and copy end address into r2.
+    // Calculate copy start address into r0 and copy end address into r4.
     // r0: actual number of arguments as a smi
     // r1: function
     // r2: expected number of arguments
@@ -1763,19 +1763,20 @@ void Builtins::Generate_ArgumentsAdaptorTrampoline(MacroAssembler* masm) {
     __ add(r0, fp, Operand::PointerOffsetFromSmiKey(r0));
     // adjust for return address and receiver
     __ add(r0, r0, Operand(2 * kPointerSize));
-    __ sub(r2, r0, Operand(r2, LSL, kPointerSizeLog2));
+    __ sub(r4, r0, Operand(r2, LSL, kPointerSizeLog2));
 
     // Copy the arguments (including the receiver) to the new stack frame.
     // r0: copy start address
     // r1: function
-    // r2: copy end address
+    // r2: expected number of arguments
     // r3: code entry to call
+    // r4: copy end address
 
     Label copy;
     __ bind(&copy);
     __ ldr(ip, MemOperand(r0, 0));
     __ push(ip);
-    __ cmp(r0, r2);  // Compare before moving to next argument.
+    __ cmp(r0, r4);  // Compare before moving to next argument.
     __ sub(r0, r0, Operand(kPointerSize));
     __ b(ne, &copy);
 
@@ -1833,20 +1834,23 @@ void Builtins::Generate_ArgumentsAdaptorTrampoline(MacroAssembler* masm) {
     // r2: expected number of arguments
     // r3: code entry to call
     __ LoadRoot(ip, Heap::kUndefinedValueRootIndex);
-    __ sub(r2, fp, Operand(r2, LSL, kPointerSizeLog2));
+    __ sub(r4, fp, Operand(r2, LSL, kPointerSizeLog2));
     // Adjust for frame.
-    __ sub(r2, r2, Operand(StandardFrameConstants::kFixedFrameSizeFromFp +
+    __ sub(r4, r4, Operand(StandardFrameConstants::kFixedFrameSizeFromFp +
                            2 * kPointerSize));
 
     Label fill;
     __ bind(&fill);
     __ push(ip);
-    __ cmp(sp, r2);
+    __ cmp(sp, r4);
     __ b(ne, &fill);
   }
 
   // Call the entry point.
   __ bind(&invoke);
+  __ mov(r0, r2);
+  // r0 : expected number of arguments
+  // r1 : function (passed through to callee)
   __ Call(r3);
 
   // Store offset of return address for deoptimizer.

diff --git a/src/arm64/builtins-arm64.cc b/src/arm64/builtins-arm64.cc
index dc86781..2dcfb1b 100644 (file)
--- a/src/arm64/builtins-arm64.cc
+++ b/src/arm64/builtins-arm64.cc
@@ -1803,19 +1803,19 @@ void Builtins::Generate_ArgumentsAdaptorTrampoline(MacroAssembler* masm) {
     Register copy_to = x12;
     Register scratch1 = x13, scratch2 = x14;
 
-    __ Lsl(argc_expected, argc_expected, kPointerSizeLog2);
+    __ Lsl(scratch2, argc_expected, kPointerSizeLog2);
 
     // Adjust for fp, lr, and the receiver.
     __ Add(copy_start, fp, 3 * kPointerSize);
     __ Add(copy_start, copy_start, Operand(argc_actual, LSL, kPointerSizeLog2));
-    __ Sub(copy_end, copy_start, argc_expected);
+    __ Sub(copy_end, copy_start, scratch2);
     __ Sub(copy_end, copy_end, kPointerSize);
     __ Mov(copy_to, jssp);
 
     // Claim space for the arguments, the receiver, and one extra slot.
     // The extra slot ensures we do not write under jssp. It will be popped
     // later.
-    __ Add(scratch1, argc_expected, 2 * kPointerSize);
+    __ Add(scratch1, scratch2, 2 * kPointerSize);
     __ Claim(scratch1, 1);
 
     // Copy the arguments (including the receiver) to the new stack frame.
@@ -1868,7 +1868,7 @@ void Builtins::Generate_ArgumentsAdaptorTrampoline(MacroAssembler* masm) {
     __ Bind(&no_strong_error);
     EnterArgumentsAdaptorFrame(masm);
 
-    __ Lsl(argc_expected, argc_expected, kPointerSizeLog2);
+    __ Lsl(scratch2, argc_expected, kPointerSizeLog2);
     __ Lsl(argc_actual, argc_actual, kPointerSizeLog2);
 
     // Adjust for fp, lr, and the receiver.
@@ -1881,7 +1881,7 @@ void Builtins::Generate_ArgumentsAdaptorTrampoline(MacroAssembler* masm) {
     // Claim space for the arguments, the receiver, and one extra slot.
     // The extra slot ensures we do not write under jssp. It will be popped
     // later.
-    __ Add(scratch1, argc_expected, 2 * kPointerSize);
+    __ Add(scratch1, scratch2, 2 * kPointerSize);
     __ Claim(scratch1, 1);
 
     // Copy the arguments (including the receiver) to the new stack frame.
@@ -1913,6 +1913,9 @@ void Builtins::Generate_ArgumentsAdaptorTrampoline(MacroAssembler* masm) {
 
   // Arguments have been adapted. Now call the entry point.
   __ Bind(&invoke);
+  __ Mov(argc_actual, argc_expected);
+  // x0 : expected number of arguments
+  // x1 : function (passed through to callee)
   __ Call(code_entry);
 
   // Store offset of return address for deoptimizer.

diff --git a/src/ia32/builtins-ia32.cc b/src/ia32/builtins-ia32.cc
index 672d698..477856c 100644 (file)
--- a/src/ia32/builtins-ia32.cc
+++ b/src/ia32/builtins-ia32.cc
@@ -1643,16 +1643,17 @@ void Builtins::Generate_ArgumentsAdaptorTrampoline(MacroAssembler* masm) {
 
     // Copy receiver and all expected arguments.
     const int offset = StandardFrameConstants::kCallerSPOffset;
-    __ lea(eax, Operand(ebp, eax, times_4, offset));
-    __ mov(edi, -1);  // account for receiver
+    __ lea(edi, Operand(ebp, eax, times_4, offset));
+    __ mov(eax, -1);  // account for receiver
 
     Label copy;
     __ bind(&copy);
-    __ inc(edi);
-    __ push(Operand(eax, 0));
-    __ sub(eax, Immediate(kPointerSize));
-    __ cmp(edi, ebx);
+    __ inc(eax);
+    __ push(Operand(edi, 0));
+    __ sub(edi, Immediate(kPointerSize));
+    __ cmp(eax, ebx);
     __ j(less, &copy);
+    // eax now contains the expected number of arguments.
     __ jmp(&invoke);
   }
 
@@ -1681,6 +1682,9 @@ void Builtins::Generate_ArgumentsAdaptorTrampoline(MacroAssembler* masm) {
     __ bind(&no_strong_error);
     EnterArgumentsAdaptorFrame(masm);
 
+    // Remember expected arguments in ecx.
+    __ mov(ecx, ebx);
+
     // Copy receiver and all actual arguments.
     const int offset = StandardFrameConstants::kCallerSPOffset;
     __ lea(edi, Operand(ebp, eax, times_4, offset));
@@ -1705,12 +1709,17 @@ void Builtins::Generate_ArgumentsAdaptorTrampoline(MacroAssembler* masm) {
     __ push(Immediate(masm->isolate()->factory()->undefined_value()));
     __ cmp(eax, ebx);
     __ j(less, &fill);
+
+    // Restore expected arguments.
+    __ mov(eax, ecx);
   }
 
   // Call the entry point.
   __ bind(&invoke);
   // Restore function pointer.
   __ mov(edi, Operand(ebp, JavaScriptFrameConstants::kFunctionOffset));
+  // eax : expected number of arguments
+  // edi : function (passed through to callee)
   __ call(edx);
 
   // Store offset of return address for deoptimizer.

diff --git a/src/x64/builtins-x64.cc b/src/x64/builtins-x64.cc
index e550835..eaae88a 100644 (file)
--- a/src/x64/builtins-x64.cc
+++ b/src/x64/builtins-x64.cc
@@ -1780,6 +1780,9 @@ void Builtins::Generate_ArgumentsAdaptorTrampoline(MacroAssembler* masm) {
 
   // Call the entry point.
   __ bind(&invoke);
+  __ movp(rax, rbx);
+  // rax : expected number of arguments
+  // rdi: function (passed through to callee)
   __ call(rdx);
 
   // Store offset of return address for deoptimizer.