[llvm] [SPIRV] Start adding support for `int128` (PR #170798)

[Alex Voicu via llvm-commits]

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@@ -0,0 +1,67 @@
+; RUN: not llc -O0 -mtriple=spirv64-unknown-unknown %s -o %t.spvt 2>&1 | FileCheck %s --check-prefix=CHECK-ERROR
+
+; RUN: llc -O0 -verify-machineinstrs -mtriple=spirv64-unknown-unknown --spirv-ext=+SPV_ALTERA_arbitrary_precision_integers %s -o - | FileCheck %s
+; TODO: %if spirv-tools %{ llc -O0 -mtriple=spirv64-unknown-unknown --spirv-ext=+SPV_ALTERA_arbitrary_precision_integers %s -o - -filetype=obj | spirv-val %}
+
+; CHECK-ERROR: LLVM ERROR: OpTypeInt type with a width other than 8, 16, 32 or 64 bits requires the following SPIR-V extension: SPV_ALTERA_arbitrary_precision_integers
+
+; CHECK: OpCapability ArbitraryPrecisionIntegersALTERA
+; CHECK: OpExtension "SPV_ALTERA_arbitrary_precision_integers"
+; CHECK: OpName %[[#TestAdd:]] "test_add"
+; CHECK: OpName %[[#TestSub:]] "test_sub"
+; CHECK: %[[#Int128Ty:]] = OpTypeInt 128 0
+; CHECK: %[[#Const64Int128:]] = OpConstant %[[#Int128Ty]] 64 0 0 0
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AlexVlx wrote:

Good question! Today it fails opaquely, with `Unsupported integer width`. With this patch it'd either pass if the required extension is present, or fail at module analysis with a slightly more informative message around needing to add the extension.

https://github.com/llvm/llvm-project/pull/170798