Reviewers: dstence, michael_dawson,
Description:
PPC: Fix constant pool overflow access in Get/SetRelocatedValue.
This resolves the mirror-object test failure.
[email protected], [email protected]
BUG=
Please review this at https://codereview.chromium.org/1214903009/
Base URL: https://chromium.googlesource.com/v8/v8.git@master
Affected files (+42, -2 lines):
M src/ppc/macro-assembler-ppc.cc
Index: src/ppc/macro-assembler-ppc.cc
diff --git a/src/ppc/macro-assembler-ppc.cc b/src/ppc/macro-assembler-ppc.cc
index
d0960cc90a4f459059fafc49a46dc29dbfb38916..4fd330a0ea44e62218adaaf967de949281422590
100644
--- a/src/ppc/macro-assembler-ppc.cc
+++ b/src/ppc/macro-assembler-ppc.cc
@@ -3247,6 +3247,7 @@ void MacroAssembler::SetRelocatedValue(Register
location, Register scratch,
lwz(scratch, MemOperand(location));
if (FLAG_enable_embedded_constant_pool) {
+ Label patch_constant, overflow_access;
if (emit_debug_code()) {
// Check that the instruction sequence is a load from the constant
pool
ExtractBitMask(scratch, scratch, 0x1f * B16);
@@ -3255,8 +3256,27 @@ void MacroAssembler::SetRelocatedValue(Register
location, Register scratch,
// Scratch was clobbered. Restore it.
lwz(scratch, MemOperand(location));
}
- // Get the address of the constant and patch it.
+
+ // Determine constant pool access type
+ ExtractBitRange(r0, scratch, 31, 26);
+ cmpi(r0, Operand(ADDIS >> 26));
+ beq(&overflow_access);
+
+ // Regular constant pool access
+ // extract the load offset
andi(scratch, scratch, Operand(kImm16Mask));
+ b(&patch_constant);
+
+ bind(&overflow_access);
+ // Overflow constant pool access
+ // shift addis immediate
+ slwi(r0, scratch, Operand(16));
+ // sign-extend and add the load offset
+ lwz(scratch, MemOperand(location, kInstrSize));
+ extsh(scratch, scratch);
+ add(scratch, r0, scratch);
+
+ bind(&patch_constant);
StorePX(new_value, MemOperand(kConstantPoolRegister, scratch));
return;
}
@@ -3345,6 +3365,7 @@ void MacroAssembler::GetRelocatedValue(Register
location, Register result,
lwz(result, MemOperand(location));
if (FLAG_enable_embedded_constant_pool) {
+ Label load_constant, overflow_access;
if (emit_debug_code()) {
// Check that the instruction sequence is a load from the constant
pool
ExtractBitMask(result, result, 0x1f * B16);
@@ -3352,8 +3373,27 @@ void MacroAssembler::GetRelocatedValue(Register
location, Register result,
Check(eq, kTheInstructionToPatchShouldBeALoadFromConstantPool);
lwz(result, MemOperand(location));
}
- // Get the address of the constant and retrieve it.
+
+ // Determine constant pool access type
+ ExtractBitRange(scratch, result, 31, 26);
+ cmpi(scratch, Operand(ADDIS >> 26));
+ beq(&overflow_access);
+
+ // Regular constant pool access
+ // extract the load offset
andi(result, result, Operand(kImm16Mask));
+ b(&load_constant);
+
+ bind(&overflow_access);
+ // Overflow constant pool access
+ // shift addis immediate
+ slwi(result, result, Operand(16));
+ // sign-extend and add the load offset
+ lwz(scratch, MemOperand(location, kInstrSize));
+ extsh(scratch, scratch);
+ add(result, result, scratch);
+
+ bind(&load_constant);
LoadPX(result, MemOperand(kConstantPoolRegister, result));
return;
}
--
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