From 2f9eb98f03b99482d3b79c7afb345d8c5014ddf8 Mon Sep 17 00:00:00 2001
From: aroulin <andy.roulin@epfl.ch>
Date: Wed, 19 Aug 2015 01:49:45 +0200
Subject: [PATCH] Shader: Save caller-saved registers in JIT before a CALL

---
 src/video_core/shader/shader_jit_x64.cpp | 30 ++++++++++++++++++++++++
 src/video_core/shader/shader_jit_x64.h   |  3 +++
 2 files changed, 33 insertions(+)

diff --git a/src/video_core/shader/shader_jit_x64.cpp b/src/video_core/shader/shader_jit_x64.cpp
index 93f608584..e4b8295b3 100644
--- a/src/video_core/shader/shader_jit_x64.cpp
+++ b/src/video_core/shader/shader_jit_x64.cpp
@@ -280,6 +280,22 @@ void JitCompiler::Compile_UniformCondition(Instruction instr) {
     CMP(sizeof(bool) * 8, MDisp(UNIFORMS, offset), Imm8(0));
 }
 
+void JitCompiler::Compile_PushCallerSavedXMM() {
+#ifndef _WIN32
+    SUB(64, R(RSP), Imm8(2 * 16));
+    MOVUPS(MDisp(RSP, 16), ONE);
+    MOVUPS(MDisp(RSP, 0), NEGBIT);
+#endif
+}
+
+void JitCompiler::Compile_PopCallerSavedXMM() {
+#ifndef _WIN32
+    MOVUPS(NEGBIT, MDisp(RSP, 0));
+    MOVUPS(ONE, MDisp(RSP, 16));
+    ADD(64, R(RSP), Imm8(2 * 16));
+#endif
+}
+
 void JitCompiler::Compile_ADD(Instruction instr) {
     Compile_SwizzleSrc(instr, 1, instr.common.src1, SRC1);
     Compile_SwizzleSrc(instr, 2, instr.common.src2, SRC2);
@@ -334,7 +350,14 @@ void JitCompiler::Compile_DP4(Instruction instr) {
 void JitCompiler::Compile_EX2(Instruction instr) {
     Compile_SwizzleSrc(instr, 1, instr.common.src1, SRC1);
     MOVSS(XMM0, R(SRC1));
+
+    // The following will actually break the stack alignment
+    ABI_PushAllCallerSavedRegsAndAdjustStack();
+    Compile_PushCallerSavedXMM();
     ABI_CallFunction(reinterpret_cast<const void*>(exp2f));
+    Compile_PopCallerSavedXMM();
+    ABI_PopAllCallerSavedRegsAndAdjustStack();
+
     SHUFPS(XMM0, R(XMM0), _MM_SHUFFLE(0, 0, 0, 0));
     MOVAPS(SRC1, R(XMM0));
     Compile_DestEnable(instr, SRC1);
@@ -343,7 +366,14 @@ void JitCompiler::Compile_EX2(Instruction instr) {
 void JitCompiler::Compile_LG2(Instruction instr) {
     Compile_SwizzleSrc(instr, 1, instr.common.src1, SRC1);
     MOVSS(XMM0, R(SRC1));
+
+    // The following will actually break the stack alignment
+    ABI_PushAllCallerSavedRegsAndAdjustStack();
+    Compile_PushCallerSavedXMM();
     ABI_CallFunction(reinterpret_cast<const void*>(log2f));
+    Compile_PopCallerSavedXMM();
+    ABI_PopAllCallerSavedRegsAndAdjustStack();
+
     SHUFPS(XMM0, R(XMM0), _MM_SHUFFLE(0, 0, 0, 0));
     MOVAPS(SRC1, R(XMM0));
     Compile_DestEnable(instr, SRC1);
diff --git a/src/video_core/shader/shader_jit_x64.h b/src/video_core/shader/shader_jit_x64.h
index 104f9f466..a6ae7fbf1 100644
--- a/src/video_core/shader/shader_jit_x64.h
+++ b/src/video_core/shader/shader_jit_x64.h
@@ -69,6 +69,9 @@ private:
     void Compile_EvaluateCondition(Instruction instr);
     void Compile_UniformCondition(Instruction instr);
 
+    void Compile_PushCallerSavedXMM();
+    void Compile_PopCallerSavedXMM();
+
     /// Pointer to the variable that stores the current Pica code offset. Used to handle nested code blocks.
     unsigned* offset_ptr = nullptr;