MSL: Add 64 bit switch support

Add 64 bit switch support for MSL version 2.2.

* Also fixes a wrong endianness conversion.

Signed-off-by: Sebastián Aedo <saedo@codeweavers.com>

16 files changed, 474 insertions, 20 deletions

diff --git a/reference/opt/shaders-msl/asm/frag/switch-different-sizes.asm.frag b/reference/opt/shaders-msl/asm/frag/switch-different-sizes.asm.frag
new file mode 100644
index 00000000..92ac1d9f
--- /dev/null
+++ b/reference/opt/shaders-msl/asm/frag/switch-different-sizes.asm.frag
@@ -0,0 +1,9 @@
+#include <metal_stdlib>
+#include <simd/simd.h>
+
+using namespace metal;
+
+fragment void main0()
+{
+}
+
diff --git a/reference/opt/shaders-msl/asm/frag/switch-long-case.asm.msl22.frag b/reference/opt/shaders-msl/asm/frag/switch-long-case.asm.msl22.frag
new file mode 100644
index 00000000..92ac1d9f
--- /dev/null
+++ b/reference/opt/shaders-msl/asm/frag/switch-long-case.asm.msl22.frag
@@ -0,0 +1,9 @@
+#include <metal_stdlib>
+#include <simd/simd.h>
+
+using namespace metal;
+
+fragment void main0()
+{
+}
+
diff --git a/reference/opt/shaders-msl/asm/frag/switch-unsigned-long-case.asm.msl22.frag b/reference/opt/shaders-msl/asm/frag/switch-unsigned-long-case.asm.msl22.frag
new file mode 100644
index 00000000..92ac1d9f
--- /dev/null
+++ b/reference/opt/shaders-msl/asm/frag/switch-unsigned-long-case.asm.msl22.frag
@@ -0,0 +1,9 @@
+#include <metal_stdlib>
+#include <simd/simd.h>
+
+using namespace metal;
+
+fragment void main0()
+{
+}
+
diff --git a/reference/opt/shaders/asm/frag/switch-preserve-sign-extension.asm.frag b/reference/opt/shaders/asm/frag/switch-preserve-sign-extension.asm.frag
new file mode 100644
index 00000000..41b98085
--- /dev/null
+++ b/reference/opt/shaders/asm/frag/switch-preserve-sign-extension.asm.frag
@@ -0,0 +1,9 @@
+#version 330
+#ifdef GL_ARB_shading_language_420pack
+#extension GL_ARB_shading_language_420pack : require
+#endif
+
+void main()
+{
+}
+
diff --git a/reference/shaders-msl/asm/frag/switch-different-sizes.asm.frag b/reference/shaders-msl/asm/frag/switch-different-sizes.asm.frag
new file mode 100644
index 00000000..1ee9eebf
--- /dev/null
+++ b/reference/shaders-msl/asm/frag/switch-different-sizes.asm.frag
@@ -0,0 +1,78 @@
+#include <metal_stdlib>
+#include <simd/simd.h>
+
+using namespace metal;
+
+fragment void main0()
+{
+    int sw0 = 42;
+    int result = 0;
+    switch (sw0)
+    {
+        case -42:
+        {
+            result = 42;
+        }
+        case 420:
+        {
+            result = 420;
+        }
+        case -1234:
+        {
+            result = 420;
+            break;
+        }
+    }
+    char sw1 = char(10);
+    switch (sw1)
+    {
+        case -42:
+        {
+            result = 42;
+        }
+        case 42:
+        {
+            result = 420;
+        }
+        case -123:
+        {
+            result = 512;
+            break;
+        }
+    }
+    short sw2 = short(10);
+    switch (sw2)
+    {
+        case -42:
+        {
+            result = 42;
+        }
+        case 42:
+        {
+            result = 420;
+        }
+        case -1234:
+        {
+            result = 512;
+            break;
+        }
+    }
+    short sw3 = short(10);
+    switch (sw3)
+    {
+        case -42:
+        {
+            result = 42;
+        }
+        case 42:
+        {
+            result = 420;
+        }
+        case -1234:
+        {
+            result = 512;
+            break;
+        }
+    }
+}
+
diff --git a/reference/shaders-msl/asm/frag/switch-long-case.asm.msl22.frag b/reference/shaders-msl/asm/frag/switch-long-case.asm.msl22.frag
new file mode 100644
index 00000000..5ec002e7
--- /dev/null
+++ b/reference/shaders-msl/asm/frag/switch-long-case.asm.msl22.frag
@@ -0,0 +1,27 @@
+#include <metal_stdlib>
+#include <simd/simd.h>
+
+using namespace metal;
+
+fragment void main0()
+{
+    long sw = 42l;
+    int result = 0;
+    switch (sw)
+    {
+        case -42l:
+        {
+            result = 42;
+        }
+        case 420l:
+        {
+            result = 420;
+        }
+        case -34359738368l:
+        {
+            result = 420;
+            break;
+        }
+    }
+}
+
diff --git a/reference/shaders-msl/asm/frag/switch-unsigned-long-case.asm.msl22.frag b/reference/shaders-msl/asm/frag/switch-unsigned-long-case.asm.msl22.frag
new file mode 100644
index 00000000..2bf44c20
--- /dev/null
+++ b/reference/shaders-msl/asm/frag/switch-unsigned-long-case.asm.msl22.frag
@@ -0,0 +1,27 @@
+#include <metal_stdlib>
+#include <simd/simd.h>
+
+using namespace metal;
+
+fragment void main0()
+{
+    ulong sw = 42ul;
+    int result = 0;
+    switch (sw)
+    {
+        case 42ul:
+        {
+            result = 42;
+        }
+        case 420ul:
+        {
+            result = 420;
+        }
+        case 343597383680ul:
+        {
+            result = 420;
+            break;
+        }
+    }
+}
+
diff --git a/reference/shaders/asm/frag/switch-preserve-sign-extension.asm.frag b/reference/shaders/asm/frag/switch-preserve-sign-extension.asm.frag
new file mode 100644
index 00000000..08921e1e
--- /dev/null
+++ b/reference/shaders/asm/frag/switch-preserve-sign-extension.asm.frag
@@ -0,0 +1,27 @@
+#version 330
+#ifdef GL_ARB_shading_language_420pack
+#extension GL_ARB_shading_language_420pack : require
+#endif
+
+void main()
+{
+    int sw = 42;
+    int result = 0;
+    switch (sw)
+    {
+        case -42:
+        {
+            result = 42;
+        }
+        case 420:
+        {
+            result = 420;
+        }
+        case -1234:
+        {
+            result = 420;
+            break;
+        }
+    }
+}
+
diff --git a/shaders-msl/asm/frag/switch-different-sizes.asm.frag b/shaders-msl/asm/frag/switch-different-sizes.asm.frag
new file mode 100644
index 00000000..ee6daa3d
--- /dev/null
+++ b/shaders-msl/asm/frag/switch-different-sizes.asm.frag
@@ -0,0 +1,106 @@
+; SPIR-V
+; Version: 1.0
+; Generator: Google Shaderc over Glslang; 10
+; Bound: 42
+; Schema: 0
+               OpCapability Shader
+               OpCapability Int8
+               OpCapability Int16
+          %1 = OpExtInstImport "GLSL.std.450"
+               OpMemoryModel Logical GLSL450
+               OpEntryPoint Fragment %main "main"
+               OpExecutionMode %main OriginUpperLeft
+               OpSource GLSL 330
+               OpSourceExtension "GL_GOOGLE_cpp_style_line_directive"
+               OpSourceExtension "GL_GOOGLE_include_directive"
+               OpName %main "main"
+               OpName %sw0 "sw0"
+               OpName %result "result"
+               OpName %sw1 "sw1"
+               OpName %sw2 "sw2"
+               OpName %sw3 "sw3"
+               OpDecorate %sw1 RelaxedPrecision
+               OpDecorate %21 RelaxedPrecision
+               OpDecorate %sw2 RelaxedPrecision
+               OpDecorate %29 RelaxedPrecision
+                     %void = OpTypeVoid
+                        %3 = OpTypeFunction %void
+                      %int = OpTypeInt 32 1
+                 %lowp_int = OpTypeInt 8 1
+                %highp_int = OpTypeInt 16 1
+        %_ptr_Function_int = OpTypePointer Function %int
+   %_ptr_Function_lowp_int = OpTypePointer Function %lowp_int
+  %_ptr_Function_highp_int = OpTypePointer Function %highp_int
+                   %int_42 = OpConstant %int 42
+                    %int_0 = OpConstant %int 0
+                  %int_420 = OpConstant %int 420
+                   %int_10 = OpConstant %int 10
+                  %int_512 = OpConstant %int 512
+              %lowp_int_10 = OpConstant %lowp_int 10
+             %highp_int_10 = OpConstant %highp_int 10
+                     %main = OpFunction %void None %3
+                        %5 = OpLabel
+                      %sw0 = OpVariable %_ptr_Function_int Function
+                   %result = OpVariable %_ptr_Function_int Function
+                      %sw1 = OpVariable %_ptr_Function_lowp_int Function
+                      %sw2 = OpVariable %_ptr_Function_highp_int Function
+                      %sw3 = OpVariable %_ptr_Function_highp_int Function
+                             OpStore %sw0 %int_42
+                             OpStore %result %int_0
+                       %12 = OpLoad %int %sw0
+                             OpSelectionMerge %16 None
+                             OpSwitch %12 %16 -42 %13 420 %14 -1234 %15
+                       %13 = OpLabel
+                             OpStore %result %int_42
+                             OpBranch %14
+                       %14 = OpLabel
+                             OpStore %result %int_420
+                             OpBranch %15
+                       %15 = OpLabel
+                             OpStore %result %int_420
+                             OpBranch %16
+                       %16 = OpLabel
+                             OpStore %sw1 %lowp_int_10
+                       %21 = OpLoad %lowp_int %sw1
+                             OpSelectionMerge %25 None
+                             OpSwitch %21 %25 -42 %22 42 %23 -123 %24
+                       %22 = OpLabel
+                             OpStore %result %int_42
+                             OpBranch %23
+                       %23 = OpLabel
+                             OpStore %result %int_420
+                             OpBranch %24
+                       %24 = OpLabel
+                             OpStore %result %int_512
+                             OpBranch %25
+                       %25 = OpLabel
+                             OpStore %sw2 %highp_int_10
+                       %29 = OpLoad %highp_int %sw2
+                             OpSelectionMerge %33 None
+                             OpSwitch %29 %33 -42 %30 42 %31 -1234 %32
+                       %30 = OpLabel
+                             OpStore %result %int_42
+                             OpBranch %31
+                       %31 = OpLabel
+                             OpStore %result %int_420
+                             OpBranch %32
+                       %32 = OpLabel
+                             OpStore %result %int_512
+                             OpBranch %33
+                       %33 = OpLabel
+                             OpStore %sw3 %highp_int_10
+                       %36 = OpLoad %highp_int %sw3
+                             OpSelectionMerge %40 None
+                             OpSwitch %36 %40 -42 %37 42 %38 -1234 %39
+                       %37 = OpLabel
+                             OpStore %result %int_42
+                             OpBranch %38
+                       %38 = OpLabel
+                             OpStore %result %int_420
+                             OpBranch %39
+                       %39 = OpLabel
+                             OpStore %result %int_512
+                             OpBranch %40
+                       %40 = OpLabel
+                             OpReturn
+                             OpFunctionEnd
diff --git a/shaders-msl/asm/frag/switch-long-case.asm.msl22.frag b/shaders-msl/asm/frag/switch-long-case.asm.msl22.frag
new file mode 100644
index 00000000..62f2dc68
--- /dev/null
+++ b/shaders-msl/asm/frag/switch-long-case.asm.msl22.frag
@@ -0,0 +1,48 @@
+; SPIR-V
+; Version: 1.0
+; Generator: Khronos SPIR-V Tools Assembler; 0
+; Bound: 21
+; Schema: 0
+               OpCapability Shader
+               OpCapability Int64
+          %1 = OpExtInstImport "GLSL.std.450"
+               OpMemoryModel Logical GLSL450
+               OpEntryPoint Fragment %main "main"
+               OpExecutionMode %main OriginUpperLeft
+               OpSource GLSL 330
+               OpSourceExtension "GL_GOOGLE_cpp_style_line_directive"
+               OpSourceExtension "GL_GOOGLE_include_directive"
+               OpName %main "main"
+               OpName %sw "sw"
+               OpName %result "result"
+       %void = OpTypeVoid
+          %6 = OpTypeFunction %void
+        %int = OpTypeInt 32 1
+       %long = OpTypeInt 64 1
+%_ptr_Function_int = OpTypePointer Function %int
+%_ptr_Function_long = OpTypePointer Function %long
+     %int_42 = OpConstant %int 42
+      %int_0 = OpConstant %int 0
+    %int_420 = OpConstant %int 420
+    %long_42 = OpConstant %long 42
+       %main = OpFunction %void None %6
+         %15 = OpLabel
+         %sw = OpVariable %_ptr_Function_long Function
+     %result = OpVariable %_ptr_Function_int Function
+               OpStore %sw %long_42
+               OpStore %result %int_0
+         %16 = OpLoad %long %sw
+               OpSelectionMerge %17 None
+               OpSwitch %16 %17 -42 %18 420 %19 -34359738368 %20
+         %18 = OpLabel
+               OpStore %result %int_42
+               OpBranch %19
+         %19 = OpLabel
+               OpStore %result %int_420
+               OpBranch %20
+         %20 = OpLabel
+               OpStore %result %int_420
+               OpBranch %17
+         %17 = OpLabel
+               OpReturn
+               OpFunctionEnd
diff --git a/shaders-msl/asm/frag/switch-unsigned-long-case.asm.msl22.frag b/shaders-msl/asm/frag/switch-unsigned-long-case.asm.msl22.frag
new file mode 100644
index 00000000..cea32b42
--- /dev/null
+++ b/shaders-msl/asm/frag/switch-unsigned-long-case.asm.msl22.frag
@@ -0,0 +1,48 @@
+; SPIR-V
+; Version: 1.0
+; Generator: Khronos SPIR-V Tools Assembler; 0
+; Bound: 21
+; Schema: 0
+               OpCapability Shader
+               OpCapability Int64
+          %1 = OpExtInstImport "GLSL.std.450"
+               OpMemoryModel Logical GLSL450
+               OpEntryPoint Fragment %main "main"
+               OpExecutionMode %main OriginUpperLeft
+               OpSource GLSL 330
+               OpSourceExtension "GL_GOOGLE_cpp_style_line_directive"
+               OpSourceExtension "GL_GOOGLE_include_directive"
+               OpName %main "main"
+               OpName %sw "sw"
+               OpName %result "result"
+       %void = OpTypeVoid
+          %6 = OpTypeFunction %void
+        %int = OpTypeInt 32 1
+       %long = OpTypeInt 64 0
+%_ptr_Function_int = OpTypePointer Function %int
+%_ptr_Function_long = OpTypePointer Function %long
+     %int_42 = OpConstant %int 42
+      %int_0 = OpConstant %int 0
+    %int_420 = OpConstant %int 420
+    %long_42 = OpConstant %long 42
+       %main = OpFunction %void None %6
+         %15 = OpLabel
+         %sw = OpVariable %_ptr_Function_long Function
+     %result = OpVariable %_ptr_Function_int Function
+               OpStore %sw %long_42
+               OpStore %result %int_0
+         %16 = OpLoad %long %sw
+               OpSelectionMerge %17 None
+               OpSwitch %16 %17 42 %18 420 %19 343597383680 %20
+         %18 = OpLabel
+               OpStore %result %int_42
+               OpBranch %19
+         %19 = OpLabel
+               OpStore %result %int_420
+               OpBranch %20
+         %20 = OpLabel
+               OpStore %result %int_420
+               OpBranch %17
+         %17 = OpLabel
+               OpReturn
+               OpFunctionEnd
diff --git a/shaders/asm/frag/switch-preserve-sign-extension.asm.frag b/shaders/asm/frag/switch-preserve-sign-extension.asm.frag
new file mode 100644
index 00000000..97140ee5
--- /dev/null
+++ b/shaders/asm/frag/switch-preserve-sign-extension.asm.frag
@@ -0,0 +1,44 @@
+; SPIR-V
+; Version: 1.0
+; Generator: Google Shaderc over Glslang; 10
+; Bound: 19
+; Schema: 0
+               OpCapability Shader
+          %1 = OpExtInstImport "GLSL.std.450"
+               OpMemoryModel Logical GLSL450
+               OpEntryPoint Fragment %main "main"
+               OpExecutionMode %main OriginUpperLeft
+               OpSource GLSL 330
+               OpSourceExtension "GL_GOOGLE_cpp_style_line_directive"
+               OpSourceExtension "GL_GOOGLE_include_directive"
+               OpName %main "main"
+               OpName %sw "sw"
+               OpName %result "result"
+       %void = OpTypeVoid
+          %3 = OpTypeFunction %void
+        %int = OpTypeInt 32 1
+%_ptr_Function_int = OpTypePointer Function %int
+     %int_42 = OpConstant %int 42
+      %int_0 = OpConstant %int 0
+    %int_420 = OpConstant %int 420
+       %main = OpFunction %void None %3
+          %5 = OpLabel
+         %sw = OpVariable %_ptr_Function_int Function
+     %result = OpVariable %_ptr_Function_int Function
+               OpStore %sw %int_42
+               OpStore %result %int_0
+         %12 = OpLoad %int %sw
+               OpSelectionMerge %16 None
+               OpSwitch %12 %16 -42 %13 420 %14 -1234 %15
+         %13 = OpLabel
+               OpStore %result %int_42
+               OpBranch %14
+         %14 = OpLabel
+               OpStore %result %int_420
+               OpBranch %15
+         %15 = OpLabel
+               OpStore %result %int_420
+               OpBranch %16
+         %16 = OpLabel
+               OpReturn
+               OpFunctionEnd
diff --git a/spirv_glsl.cpp b/spirv_glsl.cpp
index 5c21518f..9ae5d966 100644
--- a/spirv_glsl.cpp
+++ b/spirv_glsl.cpp
@@ -14768,13 +14768,13 @@ void CompilerGLSL::emit_block_chain(SPIRBlock &block)
 	case SPIRBlock::MultiSelect:
 	{
 		auto &type = expression_type(block.condition);
-		bool unsigned_case =
-		    type.basetype == SPIRType::UInt || type.basetype == SPIRType::UShort || type.basetype == SPIRType::UByte;
+		bool unsigned_case = type.basetype == SPIRType::UInt || type.basetype == SPIRType::UShort ||
+		                     type.basetype == SPIRType::UByte || type.basetype == SPIRType::UInt64;
 
 		if (block.merge == SPIRBlock::MergeNone)
 			SPIRV_CROSS_THROW("Switch statement is not structured");
 
-		if (type.basetype == SPIRType::UInt64 || type.basetype == SPIRType::Int64)
+		if (!backend.support_64bit_switch && (type.basetype == SPIRType::UInt64 || type.basetype == SPIRType::Int64))
 		{
 			// SPIR-V spec suggests this is allowed, but we cannot support it in higher level languages.
 			SPIRV_CROSS_THROW("Cannot use 64-bit switch selectors.");
@@ -14783,6 +14783,10 @@ void CompilerGLSL::emit_block_chain(SPIRBlock &block)
 		const char *label_suffix = "";
 		if (type.basetype == SPIRType::UInt && backend.uint32_t_literal_suffix)
 			label_suffix = "u";
+		else if (type.basetype == SPIRType::Int64 && backend.support_64bit_switch)
+			label_suffix = "l";
+		else if (type.basetype == SPIRType::UInt64 && backend.support_64bit_switch)
+			label_suffix = "ul";
 		else if (type.basetype == SPIRType::UShort)
 			label_suffix = backend.uint16_t_literal_suffix;
 		else if (type.basetype == SPIRType::Short)
@@ -14795,9 +14799,9 @@ void CompilerGLSL::emit_block_chain(SPIRBlock &block)
 			statement("bool _", block.self, "_ladder_break = false;");
 
 		// Find all unique case constructs.
-		unordered_map<uint32_t, SmallVector<uint32_t>> case_constructs;
+		unordered_map<uint32_t, SmallVector<uint64_t>> case_constructs;
 		SmallVector<uint32_t> block_declaration_order;
-		SmallVector<uint32_t> literals_to_merge;
+		SmallVector<uint64_t> literals_to_merge;
 
 		// If a switch case branches to the default block for some reason, we can just remove that literal from consideration
 		// and let the default: block handle it.
@@ -14806,21 +14810,17 @@ void CompilerGLSL::emit_block_chain(SPIRBlock &block)
 		auto &cases = get_case_list(block);
 		for (auto &c : cases)
 		{
-			// It's safe to cast to uint32_t since we actually do a check
-			// previously that we're not using uint64_t as the switch selector.
-			auto case_value = static_cast<uint32_t>(c.value);
-
 			if (c.block != block.next_block && c.block != block.default_block)
 			{
 				if (!case_constructs.count(c.block))
 					block_declaration_order.push_back(c.block);
-				case_constructs[c.block].push_back(case_value);
+				case_constructs[c.block].push_back(c.value);
 			}
 			else if (c.block == block.next_block && block.default_block != block.next_block)
 			{
 				// We might have to flush phi inside specific case labels.
 				// If we can piggyback on default:, do so instead.
-				literals_to_merge.push_back(case_value);
+				literals_to_merge.push_back(c.value);
 			}
 		}
 
@@ -14865,11 +14865,22 @@ void CompilerGLSL::emit_block_chain(SPIRBlock &block)
 
 		size_t num_blocks = block_declaration_order.size();
 
-		const auto to_case_label = [](uint32_t literal, bool is_unsigned_case) -> string {
-			return is_unsigned_case ? convert_to_string(literal) : convert_to_string(int32_t(literal));
+		const auto to_case_label = [](uint64_t literal, uint32_t width, bool is_unsigned_case) -> string
+		{
+			if (is_unsigned_case)
+				return convert_to_string(literal);
+
+			// For smaller cases, the literals are compiled as 32 bit wide
+			// literals so we don't need to care for all sizes specifically.
+			if (width <= 32)
+			{
+				return convert_to_string(int64_t(int32_t(literal)));
+			}
+
+			return convert_to_string(int64_t(literal));
 		};
 
-		const auto to_legacy_case_label = [&](uint32_t condition, const SmallVector<uint32_t> &labels,
+		const auto to_legacy_case_label = [&](uint32_t condition, const SmallVector<uint64_t> &labels,
 		                                      const char *suffix) -> string {
 			string ret;
 			size_t count = labels.size();
@@ -14911,7 +14922,7 @@ void CompilerGLSL::emit_block_chain(SPIRBlock &block)
 						auto &negative_literals = case_constructs[block_declaration_order[j]];
 						for (auto &case_label : negative_literals)
 							conditions.push_back(join(to_enclosed_expression(block.condition),
-							                          " != ", to_case_label(case_label, unsigned_case)));
+							                          " != ", to_case_label(case_label, type.width, unsigned_case)));
 					}
 
 					statement("if (", merge(conditions, " && "), ")");
@@ -14925,7 +14936,7 @@ void CompilerGLSL::emit_block_chain(SPIRBlock &block)
 					conditions.reserve(literals.size());
 					for (auto &case_label : literals)
 						conditions.push_back(join(to_enclosed_expression(block.condition),
-						                          " == ", to_case_label(case_label, unsigned_case)));
+						                          " == ", to_case_label(case_label, type.width, unsigned_case)));
 					statement("if (", merge(conditions, " || "), ")");
 					begin_scope();
 					flush_phi(block.self, target_block);
@@ -14940,7 +14951,7 @@ void CompilerGLSL::emit_block_chain(SPIRBlock &block)
 		// If there is only one default block, and no cases, this is a case where SPIRV-opt decided to emulate
 		// non-structured exits with the help of a switch block.
 		// This is buggy on FXC, so just emit the logical equivalent of a do { } while(false), which is more idiomatic.
-		bool degenerate_switch = block.default_block != block.merge_block && block.cases_32bit.empty();
+		bool degenerate_switch = block.default_block != block.merge_block && cases.empty();
 
 		if (degenerate_switch || is_legacy_es())
 		{
@@ -14989,7 +15000,7 @@ void CompilerGLSL::emit_block_chain(SPIRBlock &block)
 					for (auto &case_literal : literals)
 					{
 						// The case label value must be sign-extended properly in SPIR-V, so we can assume 32-bit values here.
-						statement("case ", to_case_label(case_literal, unsigned_case), label_suffix, ":");
+						statement("case ", to_case_label(case_literal, type.width, unsigned_case), label_suffix, ":");
 					}
 				}
 			}
@@ -15027,7 +15038,7 @@ void CompilerGLSL::emit_block_chain(SPIRBlock &block)
 		if ((header_merge_requires_phi && need_fallthrough_block) || !literals_to_merge.empty())
 		{
 			for (auto &case_literal : literals_to_merge)
-				statement("case ", to_case_label(case_literal, unsigned_case), label_suffix, ":");
+				statement("case ", to_case_label(case_literal, type.width, unsigned_case), label_suffix, ":");
 
 			if (block.default_block == block.next_block)
 			{
diff --git a/spirv_glsl.hpp b/spirv_glsl.hpp
index 52362442..b34ed993 100644
--- a/spirv_glsl.hpp
+++ b/spirv_glsl.hpp
@@ -586,6 +586,7 @@ protected:
 		bool needs_row_major_load_workaround = false;
 		bool support_pointer_to_pointer = false;
 		bool support_precise_qualifier = false;
+		bool support_64bit_switch = false;
 	} backend;
 
 	void emit_struct(SPIRType &type);
diff --git a/spirv_msl.cpp b/spirv_msl.cpp
index fabf2e9c..ffa69bfe 100644
--- a/spirv_msl.cpp
+++ b/spirv_msl.cpp
@@ -1355,6 +1355,7 @@ string CompilerMSL::compile()
 	backend.nonuniform_qualifier = "";
 	backend.support_small_type_sampling_result = true;
 	backend.supports_empty_struct = true;
+	backend.support_64bit_switch = true;
 
 	// Allow Metal to use the array<T> template unless we force it off.
 	backend.can_return_array = !msl_options.force_native_arrays;
diff --git a/spirv_parser.cpp b/spirv_parser.cpp
index da39367d..4faf3ca0 100644
--- a/spirv_parser.cpp
+++ b/spirv_parser.cpp
@@ -1029,7 +1029,7 @@ void Parser::parse(const Instruction &instruction)
 		{
 			for (uint32_t i = 2; i + 3 <= length; i += 3)
 			{
-				uint64_t value = (static_cast<uint64_t>(ops[i]) << 32) | ops[i + 1];
+				uint64_t value = (static_cast<uint64_t>(ops[i + 1]) << 32) | ops[i];
 				current_block->cases_64bit.push_back({ value, ops[i + 2] });
 			}
 		}