Files
clang-p2996/llvm/test/CodeGen/SPIRV/structurizer/cf.switch.opswitch.simple.ll
Nathan Gauër 1ed65febd9 [SPIR-V] Add SPIR-V structurizer (#107408)
This commit adds an initial SPIR-V structurizer.
It leverages the previously merged passes, and the convergence region
analysis to determine the correct merge and continue blocks for SPIR-V.

The first part does a branch cleanup (simplifying switches, and
legalizing them), then merge instructions are added to cycles,
convergent and later divergent blocks.
Then comes the important part: splitting critical edges, and making sure
the divergent construct boundaries don't cross.

- we split blocks with multiple headers into 2 blocks.
- we split blocks that are a merge blocks for 2 or more constructs:
SPIR-V spec disallow a merge block to be shared by 2
loop/switch/condition construct.
- we split merge & continue blocks: SPIR-V spec disallow a basic block
to be both a continue block, and a merge block.
- we remove superfluous headers: when a header doesn't bring more info
than the parent on the divergence state, it must be removed.

This PR leverages the merged SPIR-V simulator for testing, as long as
spirv-val. For now, most DXC structurization tests are passing. The
unsupported ones are either caused by unsupported features like switches
on boolean types, or switches in region exits, because the MergeExit
pass doesn't support those yet (there is a FIXME).

This PR is quite large, and the addition not trivial, so I tried to keep
it simple. E.G: as soon as the CFG changes, I recompute the dominator
trees and other structures instead of updating them.

---------

Signed-off-by: Nathan Gauër <brioche@google.com>
2024-09-20 11:36:43 +02:00

166 lines
5.2 KiB
LLVM

; RUN: llc -mtriple=spirv-unknown-vulkan-compute -O0 %s -o - | FileCheck %s
; RUN: %if spirv-tools %{ llc -O0 -mtriple=spirv-unknown-vulkan-compute %s -o - -filetype=obj | spirv-val %}
;
; int foo() { return 200; }
;
; [numthreads(1, 1, 1)]
; void main() {
; int result;
;
; int a = 0;
; switch(a) {
; case -3:
; result = -300;
; break;
; case 0:
; result = 0;
; break;
; case 1:
; result = 100;
; break;
; case 2:
; result = foo();
; break;
; default:
; result = 777;
; break;
; }
;
; switch(int c = a) {
; case -4:
; result = -400;
; break;
; case 4:
; result = 400;
; break;
; }
; }
; CHECK: %[[#func_14:]] = OpFunction %[[#uint:]] DontInline %[[#]]
; CHECK: %[[#bb25:]] = OpLabel
; CHECK: OpReturnValue %[[#]]
; CHECK: OpFunctionEnd
; CHECK: %[[#func_15:]] = OpFunction %[[#void:]] DontInline %[[#]]
; CHECK: %[[#bb26:]] = OpLabel
; CHECK: OpSelectionMerge %[[#bb27:]] None
; CHECK: OpSwitch %[[#]] %[[#bb28:]] 4294967293 %[[#bb29:]] 0 %[[#bb30:]] 1 %[[#bb31:]] 2 %[[#bb32:]]
; CHECK: %[[#bb28:]] = OpLabel
; CHECK: OpBranch %[[#bb27:]]
; CHECK: %[[#bb29:]] = OpLabel
; CHECK: OpBranch %[[#bb27:]]
; CHECK: %[[#bb30:]] = OpLabel
; CHECK: OpBranch %[[#bb27:]]
; CHECK: %[[#bb31:]] = OpLabel
; CHECK: OpBranch %[[#bb27:]]
; CHECK: %[[#bb32:]] = OpLabel
; CHECK: OpBranch %[[#bb27:]]
; CHECK: %[[#bb27:]] = OpLabel
; CHECK: OpSelectionMerge %[[#bb33:]] None
; CHECK: OpSwitch %[[#]] %[[#bb33:]] 4294967292 %[[#bb34:]] 4 %[[#bb35:]]
; CHECK: %[[#bb34:]] = OpLabel
; CHECK: OpBranch %[[#bb33:]]
; CHECK: %[[#bb35:]] = OpLabel
; CHECK: OpBranch %[[#bb33:]]
; CHECK: %[[#bb33:]] = OpLabel
; CHECK: OpReturn
; CHECK: OpFunctionEnd
; CHECK: %[[#func_23:]] = OpFunction %[[#void:]] None %[[#]]
; CHECK: %[[#bb36:]] = OpLabel
; CHECK: OpReturn
; CHECK: OpFunctionEnd
target datalayout = "e-i64:64-v16:16-v24:32-v32:32-v48:64-v96:128-v192:256-v256:256-v512:512-v1024:1024-G1"
target triple = "spirv-unknown-vulkan1.3-compute"
; Function Attrs: convergent noinline norecurse nounwind optnone
define spir_func noundef i32 @_Z3foov() #0 {
entry:
%0 = call token @llvm.experimental.convergence.entry()
ret i32 200
}
; Function Attrs: convergent nocallback nofree nosync nounwind willreturn memory(none)
declare token @llvm.experimental.convergence.entry() #1
; Function Attrs: convergent noinline norecurse nounwind optnone
define internal spir_func void @main() #0 {
entry:
%0 = call token @llvm.experimental.convergence.entry()
%result = alloca i32, align 4
%a = alloca i32, align 4
%c = alloca i32, align 4
store i32 0, ptr %a, align 4
%1 = load i32, ptr %a, align 4
switch i32 %1, label %sw.default [
i32 -3, label %sw.bb
i32 0, label %sw.bb1
i32 1, label %sw.bb2
i32 2, label %sw.bb3
]
sw.bb: ; preds = %entry
store i32 -300, ptr %result, align 4
br label %sw.epilog
sw.bb1: ; preds = %entry
store i32 0, ptr %result, align 4
br label %sw.epilog
sw.bb2: ; preds = %entry
store i32 100, ptr %result, align 4
br label %sw.epilog
sw.bb3: ; preds = %entry
%call4 = call spir_func noundef i32 @_Z3foov() #3 [ "convergencectrl"(token %0) ]
store i32 %call4, ptr %result, align 4
br label %sw.epilog
sw.default: ; preds = %entry
store i32 777, ptr %result, align 4
br label %sw.epilog
sw.epilog: ; preds = %sw.default, %sw.bb3, %sw.bb2, %sw.bb1, %sw.bb
%2 = load i32, ptr %a, align 4
store i32 %2, ptr %c, align 4
%3 = load i32, ptr %c, align 4
switch i32 %3, label %sw.epilog7 [
i32 -4, label %sw.bb5
i32 4, label %sw.bb6
]
sw.bb5: ; preds = %sw.epilog
store i32 -400, ptr %result, align 4
br label %sw.epilog7
sw.bb6: ; preds = %sw.epilog
store i32 400, ptr %result, align 4
br label %sw.epilog7
sw.epilog7: ; preds = %sw.epilog, %sw.bb6, %sw.bb5
ret void
}
; Function Attrs: convergent norecurse
define void @main.1() #2 {
entry:
call void @main()
ret void
}
attributes #0 = { convergent noinline norecurse nounwind optnone "frame-pointer"="all" "no-trapping-math"="true" "stack-protector-buffer-size"="8" }
attributes #1 = { convergent nocallback nofree nosync nounwind willreturn memory(none) }
attributes #2 = { convergent norecurse "frame-pointer"="all" "hlsl.numthreads"="1,1,1" "hlsl.shader"="compute" "no-trapping-math"="true" "stack-protector-buffer-size"="8" }
attributes #3 = { convergent }
!llvm.module.flags = !{!0, !1, !2}
!0 = !{i32 1, !"wchar_size", i32 4}
!1 = !{i32 4, !"dx.disable_optimizations", i32 1}
!2 = !{i32 7, !"frame-pointer", i32 2}