From 6ff973a06bd97dfd1c2c5191b508fdbd98f62063 Mon Sep 17 00:00:00 2001
From: Marisa Heit <rheit@users.noreply.github.com>
Date: Sun, 30 Oct 2016 22:15:40 -0500
Subject: [PATCH] Modify CMPJMP to produce more compact code (as far as VC++ is
 concerned, anyway)

---
 src/scripting/vm/vmexec.cpp | 14 +++++++----
 src/scripting/vm/vmexec.h   | 46 ++++++++++++++++++-------------------
 2 files changed, 33 insertions(+), 27 deletions(-)

diff --git a/src/scripting/vm/vmexec.cpp b/src/scripting/vm/vmexec.cpp
index 57ce48a95..af25030a9 100644
--- a/src/scripting/vm/vmexec.cpp
+++ b/src/scripting/vm/vmexec.cpp
@@ -82,11 +82,17 @@
 #define THROW(x)		throw(EVMAbortException(x))
 
 #define CMPJMP(test) \
-	if ((test) == (a & CMP_CHECK)) { \
+	pc++; \
+	if (VM_UBYTE(test) == VM_UBYTE(a)) { \
 		assert(pc[1].op == OP_JMP); \
-		pc += 1 + JMPOFS(pc+1); \
-	} else { \
-		pc += 1; \
+		pc += JMPOFS(pc); \
+	}
+
+#define CMPJMP_MASK(test) \
+	pc++; \
+	if (VM_UBYTE(test) == (VM_UBYTE(a) & CMP_CHECK)) { \
+		assert(pc[1].op == OP_JMP); \
+		pc += JMPOFS(pc); \
 	}
 
 #define GETADDR(a,o,x) \
diff --git a/src/scripting/vm/vmexec.h b/src/scripting/vm/vmexec.h
index 4b16a99d1..10b85ef86 100644
--- a/src/scripting/vm/vmexec.h
+++ b/src/scripting/vm/vmexec.h
@@ -1199,88 +1199,88 @@ begin:
 		ASSERTF(B); ASSERTF(C);
 		if (a & CMP_APPROX)
 		{
-			CMPJMP(fabs(reg.f[C] - reg.f[B]) < VM_EPSILON);
+			CMPJMP_MASK(fabs(reg.f[C] - reg.f[B]) < VM_EPSILON);
 		}
 		else
 		{
-			CMPJMP(reg.f[C] == reg.f[B]);
+			CMPJMP_MASK(reg.f[C] == reg.f[B]);
 		}
 		NEXTOP;
 	OP(EQF_K):
 		ASSERTF(B); ASSERTKF(C);
 		if (a & CMP_APPROX)
 		{
-			CMPJMP(fabs(konstf[C] - reg.f[B]) < VM_EPSILON);
+			CMPJMP_MASK(fabs(konstf[C] - reg.f[B]) < VM_EPSILON);
 		}
 		else
 		{
-			CMPJMP(konstf[C] == reg.f[B]);
+			CMPJMP_MASK(konstf[C] == reg.f[B]);
 		}
 		NEXTOP;
 	OP(LTF_RR):
 		ASSERTF(B); ASSERTF(C);
 		if (a & CMP_APPROX)
 		{
-			CMPJMP((reg.f[B] - reg.f[C]) < -VM_EPSILON);
+			CMPJMP_MASK((reg.f[B] - reg.f[C]) < -VM_EPSILON);
 		}
 		else
 		{
-			CMPJMP(reg.f[B] < reg.f[C]);
+			CMPJMP_MASK(reg.f[B] < reg.f[C]);
 		}
 		NEXTOP;
 	OP(LTF_RK):
 		ASSERTF(B); ASSERTKF(C);
 		if (a & CMP_APPROX)
 		{
-			CMPJMP((reg.f[B] - konstf[C]) < -VM_EPSILON);
+			CMPJMP_MASK((reg.f[B] - konstf[C]) < -VM_EPSILON);
 		}
 		else
 		{
-			CMPJMP(reg.f[B] < konstf[C]);
+			CMPJMP_MASK(reg.f[B] < konstf[C]);
 		}
 		NEXTOP;
 	OP(LTF_KR):
 		ASSERTKF(B); ASSERTF(C);
 		if (a & CMP_APPROX)
 		{
-			CMPJMP((konstf[B] - reg.f[C]) < -VM_EPSILON);
+			CMPJMP_MASK((konstf[B] - reg.f[C]) < -VM_EPSILON);
 		}
 		else
 		{
-			CMPJMP(konstf[B] < reg.f[C]);
+			CMPJMP_MASK(konstf[B] < reg.f[C]);
 		}
 		NEXTOP;
 	OP(LEF_RR):
 		ASSERTF(B); ASSERTF(C);
 		if (a & CMP_APPROX)
 		{
-			CMPJMP((reg.f[B] - reg.f[C]) <= -VM_EPSILON);
+			CMPJMP_MASK((reg.f[B] - reg.f[C]) <= -VM_EPSILON);
 		}
 		else
 		{
-			CMPJMP(reg.f[B] <= reg.f[C]);
+			CMPJMP_MASK(reg.f[B] <= reg.f[C]);
 		}
 		NEXTOP;
 	OP(LEF_RK):
 		ASSERTF(B); ASSERTKF(C);
 		if (a & CMP_APPROX)
 		{
-			CMPJMP((reg.f[B] - konstf[C]) <= -VM_EPSILON);
+			CMPJMP_MASK((reg.f[B] - konstf[C]) <= -VM_EPSILON);
 		}
 		else
 		{
-			CMPJMP(reg.f[B] <= konstf[C]);
+			CMPJMP_MASK(reg.f[B] <= konstf[C]);
 		}
 		NEXTOP;
 	OP(LEF_KR):
 		ASSERTKF(B); ASSERTF(C);
 		if (a & CMP_APPROX)
 		{
-			CMPJMP((konstf[B] - reg.f[C]) <= -VM_EPSILON);
+			CMPJMP_MASK((konstf[B] - reg.f[C]) <= -VM_EPSILON);
 		}
 		else
 		{
-			CMPJMP(konstf[B] <= reg.f[C]);
+			CMPJMP_MASK(konstf[B] <= reg.f[C]);
 		}
 		NEXTOP;
 
@@ -1369,12 +1369,12 @@ begin:
 	Do_EQV2:
 		if (a & CMP_APPROX)
 		{
-			CMPJMP(fabs(reg.f[B  ] - fcp[0]) < VM_EPSILON &&
-				   fabs(reg.f[B+1] - fcp[1]) < VM_EPSILON);
+			CMPJMP_MASK(fabs(reg.f[B  ] - fcp[0]) < VM_EPSILON &&
+						fabs(reg.f[B+1] - fcp[1]) < VM_EPSILON);
 		}
 		else
 		{
-			CMPJMP(reg.f[B] == fcp[0] && reg.f[B+1] == fcp[1]);
+			CMPJMP_MASK(reg.f[B] == fcp[0] && reg.f[B+1] == fcp[1]);
 		}
 		NEXTOP;
 	OP(EQV2_K):
@@ -1496,13 +1496,13 @@ begin:
 	Do_EQV3:
 		if (a & CMP_APPROX)
 		{
-			CMPJMP(fabs(reg.f[B  ] - fcp[0]) < VM_EPSILON &&
-				   fabs(reg.f[B+1] - fcp[1]) < VM_EPSILON &&
-				   fabs(reg.f[B+2] - fcp[2]) < VM_EPSILON);
+			CMPJMP_MASK(fabs(reg.f[B  ] - fcp[0]) < VM_EPSILON &&
+						fabs(reg.f[B+1] - fcp[1]) < VM_EPSILON &&
+					    fabs(reg.f[B+2] - fcp[2]) < VM_EPSILON);
 		}
 		else
 		{
-			CMPJMP(reg.f[B] == fcp[0] && reg.f[B+1] == fcp[1] && reg.f[B+2] == fcp[2]);
+			CMPJMP_MASK(reg.f[B] == fcp[0] && reg.f[B+1] == fcp[1] && reg.f[B+2] == fcp[2]);
 		}
 		NEXTOP;
 	OP(EQV3_K):