[wasm][liftoff][x64] Allow more GpCacheRegs

r8, r12, and r15 should be usable as general allocatable registers.
This is a performance experiment. If it causes more regressions than
improvements, we can simply revert it.

Change-Id: I757c06e9d0fc760e900b228b92671d6710bf4560
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3782672
Auto-Submit: Jakob Kummerow <jkummerow@chromium.org>
Commit-Queue: Clemens Backes <clemensb@chromium.org>
Reviewed-by: Clemens Backes <clemensb@chromium.org>
Cr-Commit-Position: refs/heads/main@{#81897}

src/execution/x64/frame-constants-x64.h

@@ -61,7 +61,8 @@ class WasmCompileLazyFrameConstants : public TypedFrameConstants {
 // registers (see liftoff-assembler-defs.h).
 class WasmDebugBreakFrameConstants : public TypedFrameConstants {
  public:
-  static constexpr RegList kPushedGpRegs = {rax, rcx, rdx, rbx, rsi, rdi, r9};
+  static constexpr RegList kPushedGpRegs = {rax, rcx, rdx, rbx, rsi,
+                                            rdi, r8,  r9,  r12, r15};
 
   static constexpr DoubleRegList kPushedFpRegs = {xmm0, xmm1, xmm2, xmm3,
                                                   xmm4, xmm5, xmm6, xmm7};

src/wasm/baseline/liftoff-assembler-defs.h

@@ -23,8 +23,12 @@ constexpr DoubleRegList kLiftoffAssemblerFpCacheRegs = {xmm0, xmm1, xmm2, xmm3,
 
 #elif V8_TARGET_ARCH_X64
 
-constexpr RegList kLiftoffAssemblerGpCacheRegs = {rax, rcx, rdx, rbx,
-                                                  rsi, rdi, r9};
+// r10: kScratchRegister (MacroAssembler)
+// r11: kScratchRegister2 (Liftoff)
+// r13: kRootRegister
+// r14: kPtrComprCageBaseRegister
+constexpr RegList kLiftoffAssemblerGpCacheRegs = {rax, rcx, rdx, rbx, rsi,
+                                                  rdi, r8,  r9,  r12, r15};
 
 constexpr DoubleRegList kLiftoffAssemblerFpCacheRegs = {xmm0, xmm1, xmm2, xmm3,
                                                         xmm4, xmm5, xmm6, xmm7};