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Signed-off-by: Takeshi Yoneda <[email protected]>
tetratelabs · Mar 5, 2024 · a935e35 · a935e35
1 parent 0599763
commit a935e35
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Showing 2 changed files with 4 additions and 1 deletion.
diff --git a/internal/engine/wazevo/frontend/frontend.go b/internal/engine/wazevo/frontend/frontend.go
@@ -56,7 +56,7 @@ type Compiler struct {
 	knownSafeBounds    [] /* ssa.ValueID to */ knownSafeBound
 	knownSafeBoundsSet []ssa.ValueID
 
-	knownSafeBoundsAtTheEndOfBlocks   [] /* ssa.ValueID to */ knownSafeBoundsAtTheEndOfBlock
+	knownSafeBoundsAtTheEndOfBlocks   [] /* ssa.BlockID to */ knownSafeBoundsAtTheEndOfBlock
 	varLengthKnownSafeBoundWithIDPool wazevoapi.VarLengthPool[knownSafeBoundWithID]
 
 	execCtxPtrValue, moduleCtxPtrValue ssa.Value

diff --git a/internal/engine/wazevo/frontend/lower.go b/internal/engine/wazevo/frontend/lower.go
@@ -165,7 +165,10 @@ func (c *Compiler) lowerBody(entryBlk ssa.BasicBlock) {
 		c.lowerCurrentOpcode()
 		blkAfterLowering := c.ssaBuilder.CurrentBlock()
 		if blkBeforeLowering != blkAfterLowering {
+			// In Wasm, once a block exits, that means we've done compiling the block.
+			// Therefore, we finalize the known bounds at the end of the block for the exiting block.
 			c.finalizeKnownSafeBoundsAtTheEndOfBlock(blkBeforeLowering.ID())
+			// After that, we initialize the known bounds for the new compilation target block.
 			c.initializeCurrentBlockKnownBounds()
 		}
 	}