[Wasm RyuJit] Null checks for calls, overflow checks for int to int casts, resolve stack ordering, more

[AndyAyersMS]

Various fixes from running crossgen

• fix return type classification for structs returned as primitives
• null checks for calls
• overflow checks for int to int casts
• stack ordering and null check for delegate invoke
• stack ordering for NOT

[AndyAyersMS]

Sample codegen for ulong -> uint.

Note I am seeing apparently unneeded local declarations like in the below.

G_M6689_IG01:        ; func=00, offs=0x000000, size=0x0003, bbWeight=1, PerfScore 2.00, gcrefRegs=00000000, byrefRegs=00000000, byref, nogc <-- Prolog IG

IN000d: 000000      local.cnt 1
IN000e: 000001      local[3] type=i64

G_M6689_IG02:        ; offs=0x000003, size=0x0002, bbWeight=1, PerfScore 1.00, gcrefRegs=00000000, byrefRegs=00000000, BB01 [0000], byref

IN0001: 000003      block

G_M6689_IG03:        ; offs=0x000005, size=0x000E, bbWeight=1, PerfScore 6.00, gcrefRegs=00000000, byrefRegs=00000000, BB01 [0000], byref

IN0002: 000005      local.get 1
IN0003: 000007      local.get 1
IN0004: 000009      i64.const 4294967295
IN0005: 00000F      i64.gt_u
IN0006: 000010      br_if 0      ;; G_M6689_IG05
IN0007: 000012      i32.wrap_i64

G_M6689_IG04:        ; offs=0x000013, size=0x0001, bbWeight=1, PerfScore 1.00, epilog, nogc, extend

IN000f: 000013      return

G_M6689_IG05:        ; offs=0x000014, size=0x000C, bbWeight=0, PerfScore 0.00, gcVars=0000000000000000 {}, gcrefRegs=00000000, byrefRegs=00000000, BB02 [0001], gcvars, byref

IN0008: 000014      end
IN0009: 000015      local.get 0
IN000a: 000017      i32.const 0
IN000b: 000019      call 0      ;; CORINFO_HELP_OVERFLOW
IN000c: 00001F      unreachable

[Copilot]

Pull request overview

This PR implements three WASM codegen improvements: fixing return type classification for structs returned as primitives, adding null checks for calls, and implementing overflow checks for integer-to-integer casts.

Changes:

• Fixed struct return type classification to use SPK_PrimitiveType instead of SPK_ByValue when WASM returns structs as primitive types
• Added null check support for WASM calls that need them, with proper register allocation and code generation
• Implemented overflow checking for integer-to-integer casts in WASM codegen

Reviewed changes

Copilot reviewed 9 out of 9 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
src/coreclr/jit/compiler.cpp	Fixed return type classification to use SPK_PrimitiveType for WASM structs returned as primitives
src/coreclr/jit/gentree.cpp	Added empty WASM case in InitializeStructReturnType for SPK_ByValue handling
src/coreclr/jit/lower.cpp	Mark thisArg as multiply-used for WASM calls needing null checks
src/coreclr/jit/lowerwasm.cpp	Mark cast operands as multiply-used when overflow checks are needed
src/coreclr/jit/stacklevelsetter.cpp	Register throw helper blocks for WASM calls needing null checks
src/coreclr/jit/regallocwasm.h	Added method declarations for call and cast reference collection
src/coreclr/jit/regallocwasm.cpp	Implemented register reference collection for calls and casts with checks
src/coreclr/jit/codegenwasm.cpp	Implemented overflow checking and null checking code generation for WASM
src/coreclr/jit/codegenarm.cpp	CRITICAL BUG: Incorrect code added that will not compile

[AndyAyersMS]

@dotnet/jit-contrib PTAL

[Copilot]

Pull request overview

Copilot reviewed 9 out of 9 changed files in this pull request and generated 2 comments.

[dotnet-policy-service]

Tagging subscribers to 'arch-wasm': @lewing, @pavelsavara
See info in area-owners.md if you want to be subscribed.

[Copilot]

Pull request overview

Copilot reviewed 12 out of 12 changed files in this pull request and generated no new comments.

[SingleAccretion]

LGTM modulo the delegate invoke question and comments.